SPIN - Droplet Measurement Technologies

Operator Manual
DOC-0328 Revision B-3
Software Version 4.0.0
2545 Central Avenue
Boulder, CO 80301-5727 USA
COPYRIGHT © 2013 DROPLET MEASUREMENT TECHNOLOGIES,
INC.
Spectrometer for Ice Nuclei (SPIN) Operator Manual
Copyright © 2013 Droplet Measurement Technologies, Inc.
2545 CENTRAL AVENUE
BOULDER, COLORADO, USA 80301-5727
TEL: +1 (303) 440-5576
FAX: +1 (303) 440-1965
WWW.DROPLETMEASUREMENT.COM
All rights reserved. No part of this document shall be reproduced, stored in a retrieval system, or
transmitted by any means, electronic, mechanical, photocopying, recording, or otherwise, without written
permission from Droplet Measurement Technologies, Inc. Although every precaution has been taken in
the preparation of this document, Droplet Measurement Technologies, Inc. assumes no responsibility for
errors or omissions. Neither is any liability assumed for damages resulting from the use of the information
contained herein.
Information in this document is subject to change without prior notice in order to improve accuracy,
design, and function and does not represent a commitment on the part of the manufacturer. Information
furnished in this manual is believed to be accurate and reliable. However, no responsibility is assumed for
its use, or any infringements of patents or other rights of third parties, which may result from its use.
Trademark Information
All Droplet Measurement Technologies, Inc. product names and the Droplet Measurement Technologies,
Inc. logo are trademarks of Droplet Measurement Technologies, Inc.
All other brands and product names are trademarks or registered trademarks of their respective owners.
Warranty
The seller warrants that the equipment supplied will be free from defects in material and workmanship for
a period of one year from the confirmed date of purchase of the original buyer. Service procedures and
repairs are warrantied for 90 days. The equipment owner will pay for shipping to DMT, while DMT covers
the return shipping expense.
Consumable components, such as tubing, filters, pump diaphragms, and Nafion humidifiers and
dehumidifiers are not covered by this warranty.
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CONTENTS
1.0
Introduction ................................................................................ 7
2.0
Overview of Operation .................................................................. 8
2.1
SPIN Components ................................................................................ 8
2.2
Labeled Photographs ........................................................................... 10
2.2.1 Overall Instrument ......................................................................... 10
2.2.2 Inlet........................................................................................... 12
2.2.3 Flow Acquisition Box ....................................................................... 13
2.2.4 Control Box .................................................................................. 14
2.2.5 Cold Plate Refrigeration Valves .......................................................... 15
2.2.6 Detector Box ................................................................................ 16
2.3
Front Panel LEDs ................................................................................ 17
2.4
Safety Precautions .............................................................................. 18
2.4.1 Protecting Compressors from Over-Pressurizing ....................................... 18
2.4.2 “Purge Sample Tube” Sequence—Protecting Detector Box from Accidental Water
Exposure ............................................................................................... 18
3.0
Overview of SPIN Software ........................................................... 19
3.1
Getting Help from Within the Software ..................................................... 20
3.2
About Sequences ................................................................................ 20
3.2.1 About Exit Steps ............................................................................ 20
3.2.2 Running Sequences Concurrently ......................................................... 21
3.3
Changing and Saving Configuration Files .................................................... 21
3.4
Creating User-Defined Calculations .......................................................... 21
3.4.1 Creating Calculated Channels ............................................................ 21
3.4.2 Using Pre-defined, LabVIEW-based Calculations ....................................... 22
3.4.3 User-created LabVIEW Calculations...................................................... 23
3.5
Creating and Editing Sequences .............................................................. 23
4.0
Starting up the System ................................................................ 24
4.1
4.2
4.3
Overview ......................................................................................... 24
Changing the Inlet and Outlet Valve Positions.............................................. 25
Step-by-Step Instructions ...................................................................... 25
5.0
Shutting Down the System ............................................................ 27
6.0
Ice Nuclei Chamber..................................................................... 30
6.1.1
6.1.2
6.1.3
7.0
Cooling Loops ............................................................................... 31
Refrigerant Compressors .................................................................. 31
Icing the Chamber .......................................................................... 31
Optical Particle Counter (OPC) ...................................................... 32
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7.1
Optics ............................................................................................. 32
7.2
Amplification of Particle Signals .............................................................. 33
7.3
Data Analysis with the PbP File—Correcting for Different Amplification Levels ....... 34
7.3.1 Depolarization Data Analysis ............................................................. 38
8.0
SPIN Software Tabs ..................................................................... 41
8.1
SPIN Tab .......................................................................................... 41
8.2
Control Tab ...................................................................................... 42
8.2.1 Controller Channels ........................................................................ 43
8.2.2 Sequence Switches ......................................................................... 43
8.2.3 Digital Outputs .............................................................................. 45
8.2.4 Channels ..................................................................................... 46
8.2.5 Detector Controller ........................................................................ 46
8.2.6 Alicat Flow Controller ..................................................................... 46
8.2.7 “Set Any Output Channel Here” .......................................................... 46
8.3
Status Tab........................................................................................ 46
8.4
Sequences Tab .................................................................................. 48
8.5
Custom Tab (Optional) ......................................................................... 49
8.6
Config Tab ....................................................................................... 50
8.6.1 Program Sub-tab ............................................................................ 50
8.6.2 Acquisition Sub-tab......................................................................... 54
8.6.3 Analog In Sub-Tab .......................................................................... 56
8.6.4 Digital I/O ................................................................................... 58
8.6.5 Flow and Control Sub-Tab ................................................................. 60
8.6.6 Alarms and Timers Sub-tab ............................................................... 68
8.6.7 Calculations Sub-Tab ....................................................................... 72
8.6.8 Communication Sub-Tab ................................................................... 74
8.6.9 Sequences Sub-Tab ......................................................................... 77
8.6.10
Custom Sub-tab........................................................................... 80
8.7
Utility Tab ....................................................................................... 82
8.7.1 SPIN Data Reader Program ................................................................ 83
8.7.2 SPIN Log Reader ............................................................................. 84
8.7.3 Sequence Editor............................................................................. 85
9.0
Troubleshooting ......................................................................... 87
Appendix A: Specifications ..................................................................... 87
Appendix B: SPIN Software Architecture .................................................... 88
Appendix C: Output Files ..................................................................... 89
*.csv Files ................................................................................................ 89
Main Data File ........................................................................................ 89
PbP Files ..............................................................................................103
*.log File.................................................................................................103
*.ini Files ................................................................................................103
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Appendix D: Calculations for Derived Channels ..........................................104
Appendix E: SPIN Actions ......................................................................108
Appendix F: Remote Communication Format via CCL ...................................109
Appendix G: Syntax for Calculated Channels ..............................................111
Appendix H: Refrigerant Information .......................................................113
Appendix I: Compressor Controller--Specifications ......................................114
Appendix J: ILS Industrial Laser System Instruction Manual ...........................115
Appendix K: Aerosol Controller Plot.........................................................116
Appendix L: Revisions to Manual .............................................................116
Figures
Figure 1: The Spectrometer for Ice Nuclei (SPIN) ........................................... 7
Figure 2: SPIN Diagram—Front View with Component sLabeled ......................... 8
Figure 3: SPIN Air and Water Flow Diagram .................................................. 9
Figure 4: SPIN Front View with Components Labeled .................................... 10
Figure 5: Left Side View of SPIN with Components Labeled ............................ 11
Figure 6: SPIN Inlet ............................................................................... 12
Figure 7: Flow Acquisition Box with Components Labeled .............................. 13
Figure 8: Control Box with Components Labeled.......................................... 14
Figure 9: Cold-Plate Refrigeration Valves ................................................... 15
Figure 10: Detector-Chamber Interface ..................................................... 16
Figure 11: LED Indicators and Corresponding Status of the SPIN ...................... 17
Figure 12: Detail from SPIN Flow Diagram Showing Purge Valve, L3 Sensor, 3-way
OPC Valve, and Water Pump .............................................................. 18
Figure 13: Modifying the "Start Compressors" Sequence ................................ 24
Figure 14: SPIN Software Controls for the Inlet and Outlet Valves .................... 25
Figure 15: SPIN Front Panel Switches ........................................................ 26
Figure 16: Chamber Water Return Configured for Drying Chamber .................. 28
Figure 17: The SPIN Configured with an External Pump for Drying the Chamber . 29
Figure 18: Conceptual Diagram of Ice Nuclei Chamber .................................. 30
Figure 19: Conceptual Drawing of Refrigerant Loops (Not to Scale) .................. 31
Figure 20: SPIN Optical Diagram............................................................... 32
Figure 21: Optics in Detector Box ............................................................ 33
Figure 22: Signal-Amplification Electronics................................................. 34
Figure 23: Raw Data Counts for Limonene Droplets ...................................... 36
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Figure
Figure
Figure
Figure
Figure
Figure
Figure
Figure
Figure
Figure
Figure
Figure
Figure
Figure
Figure
Figure
Figure
Figure
Figure
Figure
Figure
Figure
Figure
Figure
Figure
Figure
Figure
Figure
24: Data in Previous FigureCorrected for Amplifier Gain ...................... 37
25: Scatter Plot of the S1/P1.......................................................... 38
26: S1/P1 Polarization of Volcanic Ash ............................................. 39
27: S1 / P1Polarization Ratio for Water Droplets ................................ 40
28: SPIN Tab .............................................................................. 41
29: Control for Determining the Time Range of Displayed Data .............. 42
30: Control Tab .......................................................................... 43
31: Control Tab while “Compressors Starting” Sequence is Running ....... 44
32: Status Tab ............................................................................ 47
33: Sequences Tab ...................................................................... 49
34: Program Sub-tab .................................................................... 51
35: Acquisition Sub-tab ................................................................ 54
36: Analog In Sub-tab ................................................................... 56
37: Digital I/O Sub-tab .................................................................. 58
38:Config Tab—Flow Sub-Tab ......................................................... 61
39: Alarms and Timers Sub-tab ....................................................... 69
40: Calculations Sub-tab--Important Components ............................... 72
41: Communication Sub-tab ........................................................... 74
42: Selecting a Channel for Inclusion in Streamed Output Data .............. 76
43: Sequences Sub-tab ................................................................. 77
44: Example Sequence Switch on Control Tab .................................... 78
45: Using the Config > Custom Tab to Name and Define a Custom Tab ..... 81
46: SPIN Data Reader ................................................................... 83
47: Data Reader Time Controls ....................................................... 84
48: Utility Tab—SPIN Log Reader ..................................................... 85
49: UtilityTab—SPIN Sequence Editor ............................................... 86
50: Hypothetical LWC and cum(i) Data ............................................107
51: Shifting Temperatures with the Aerosol Controller IV Sequence .......116
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1.0
Introduction
The Spectrometer for Ice Nuclei (SPIN) is the first commercially available ice nuclei counter, with
a particle detection range from 1 – 20 µm. Particle detection allows for individual particle sizing
and discrimination of ice and water particles using polarization change in the scattered light.
Figure 1: The Spectrometer for Ice Nuclei (SPIN)
For SPIN specifications, see Appendix A.
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2.0
Overview of Operation
The SPIN’s chamber design is based on parallel-plate geometry.1 This design provides easy and
uniform cooling. A compact refrigeration system cools the plates directly, eliminating the need for
external cooling baths and heat exchange fluids.
2.1
SPIN Components
The SPIN consists of the following components:

The Ice Nuclei Chamber contains the refrigerated plates that cool the sample air.

The Flow Acquisition Box contains the pumps, data acquisition system, and mass flow
controllers.

The Control Box contains electronics such as pump controls.

The Warm and Cold Refrigeration Assemblies contain the compressors that drive
refrigerant into the plates.

The Detector Box consists of the laser, two standard light-scattering detectors and two
polarized light detectors. The polarized light detectors allow discrimination of ice
particles from other particles.
Figure 2: SPIN Diagram—Front View with Component sLabeled
1
The parallel plate chamber follows the design of Stetzer and engineering team at the ETH-Zurich.
Details are given in Chou et. al., (Atmos. Chem. Phys., 11, 4725-4738, 2011). The construction of
the SPIN chamber is similar to the Portable Ice Nucleation Chamber (PINC) referenced in this paper.
The SPIN evaporation system incorporates some changes that differ from the PINC instrument as do
the control electronics, software, refrigeration system, and depolarization detector, which are of DMT
design and construction.
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Figure 3: SPIN Air and Water Flow Diagram
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2.2
Labeled Photographs
The following photographs and diagrams below illustrate the different components of the SPIN
in more detail.
2.2.1
Overall Instrument
Control Box
Flow Acquisition Box
Cold1 and 2 Refrig Drawer
Warm Refrig Drawer
Figure 4: SPIN Front View with Components Labeled
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Components:
1
2
3
4
1
2
3
5
6
7
8
9
10
11
4
5
6
12
Liquid Level 2 Sensor
Cold plate
Warm plate
Ice Nuclei chamber
temperature controller
Flow acquisition box
Sheath air filter
SPIN 28V power supply
Cold1 comp controller
Cold2 comp controller
Warm comp controller
Refrigeration comp
temperature controller
Water reservoir
7
8
9
0
10
11
12
Figure 5: Left Side View of SPIN with Components Labeled
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2.2.2
Inlet
DIFFERENTIAL
PRESSURE
TRANSDUCER
(SHEATH SAMPLE)
Figure 6: SPIN Inlet
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2.2.3
Flow Acquisition Box
1
2
3
10
4
5
11
6
12
7
9
8
13
Figure 7: Flow Acquisition Box with Components Labeled
Components:
1
2
3
4
5
6
7
8
9
10
11
12
13
Sheath Air Filter
SPIN System 28V Power Supply
NI 9403 32-channel Digital I/O
NI 9264 16-channel Analog Out
NI 9205 32-channel Analog In (underneath cord)
NI 9213 16-channel Thermocouple In (underneath cord)
NI 9402 4-channel Digital I/O
NI cDAQ-9178
Sheath Pump
Mass Flow Controller for Sample Flow (1 L/Min)
Mass Flow Controller for Sheath Flow (10 L/Min)
Air Inlet Valve
Sample Pump
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2.2.4
Control Box
Valve
Actuator
Supply
220 VAC
Distribution
Valve
Actuator
Supply
3A 28V
Breaker
Valve
Actuator
Supply
15A AC
breaker
Figure 8: Control Box with Components Labeled
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2.2.5
Cold Plate Refrigeration Valves
COLD PLATE
MIDBOTTOM
REFRIG VALVE
COLD PLATE
BOTTOM
REFRIG VALVE
Figure 9: Cold-Plate Refrigeration Valves
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2.2.6
Detector Box
At the bottom of the SPIN, beneath the Ice Nuclei Chamber and the Evaporator, is the
Detector Box. Figure 10 shows the interface between the Chamber and the Detector Box,
whileFigure 21 diagrams the optics in the detector box.
4
1
3
5
2
6
9
7
10
8
11
Figure 10: Detector-Chamber Interface
Components:
1
2
3
4
5
6
7
8
9
10
11
Water isolation valve (purge valve is behind this valve
Water feed line
Liquid Level 3 sensor (indicates if there is water in the line)
Sample Tube tee
Outlet valve
Outlet valve actuator
Detector inlet
Laser
S1 Detector
P1 Detector (P2 and Size detectors not visible in photo)
The four electronic boards, from front to back:
- Power board (ABD-0005), with laser power interface board on back side of card gauge
- Baseline restoration board (ABD-0043)
- CAS Digital iii board (ABD-0192)
- TEC control board (ABD-0138)
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2.3
Front Panel LEDs
The SPIN’s front panel contains six LEDs that provide diagnostics and information about the
instrument’s status. LEDs can display as blue, green, or red. The table below shows what
different colors LEDs indicate about the SPIN’s status.
Figure 11: LED Indicators and Corresponding Status of the SPIN
Note: A blue STATUS indicator means particle-laden air is flowing into the SPIN inlet. It does not
necessarily mean the optics are detecting particles. The latter condition is indicated by a blue
SAMPLE light.
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2.4
Safety Precautions
The SPIN is equipped with several safety precautions to prevent damage to the instrument.
2.4.1
Protecting Compressors from Over-Pressurizing
To avoid damage to the SPIN compressors, the software automatically shuts down any
compressor where the outlet pressure exceeds 350 psi.
2.4.2
“Purge Sample Tube” Sequence—Protecting
Accidental Water Exposure
Detector
Box
from
The Purge Sample Tube sequence is designed to purge the sample tube of any water pooled
in the line. This prevents water from flooding the detector box and damaging the optics.
Before a purge, the user typically performs an Empty Chamber sequence. During this
sequence the water pump drains water from the chamber. However, since the water pump is
located above the 3-way valve for the optical particle counter (OPC), water can still remain
in and above the valve. If the valve is then opened, this water can then flood the OPC. This
can cause severe damage to the optics.
(L3)
Figure 12: Detail from SPIN Flow Diagram Showing Purge Valve, L3 Sensor, 3-way OPC Valve, and Water Pump
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The Purge sequence removes this excess water. The purge valve opens, and a blast of air
shoots the water shoots through the 3-way OPC valve up into the chamber. This procedure
repeats until the Liquid Level 3 (L3) sensor detects no water.
Note: As an extra precaution, the user is also advised to remove the detector box before
warming the instrument.
3.0
Overview of SPIN Software
The SPIN software is designed in LabVIEW, a program that provides a user-friendly virtual
instrument panel for the control, data display, and data logging of the SPIN instrument. This
manual describes version 4.0.0 of the SPIN software.
To start the program, double-click on the SPIN icon on the desktop. The SPIN Tab is the
displayed upon start-up. Several other tabs are displayed at the top of the screen. Clicking on
these tabs will bring up different displays, as follows:
1. SPIN Tab – Displays a histogram of particle counts and two or three time-series charts
of user-selectable channels
2. Control Tab – Used to control the flow and temperature set points, turn sequences on
and off, and monitorand control the SPINhousekeeping channels.
3. Status Tab—Displays information about the SPIN software, including output file
locations, error logs, alarms, and configuration settings.
4. Sequences Tab—Allows the user to view and run sequences (see “About Sequences” in
section 3.2).
5. Config Tab—Allows the user to view and edit the settings for the SPIN software. This
tab has many sub-tabs, and changes to these settings should be made with great
caution.
6. Utility Tab—Provides access to utilities.
Your SPIN software may have an additional tab between the Sequences and Config tabs—for
example, a Compressors tab. This customized tab appears if it has been named and
configured on the Config > Custom tab.
The top of the screen, above the tabs, displays key information about the program. The
Alarm button indicates whether an alarm is currently active. When the button is red, an
alarm has been generated; a green button indicates normal operation. Yellow indicates a
warning: an Alarm condition has been met, but the “Min Time” required has not yet elapsed.
The Do Not Write to Data File / Write to Data File switch allows the user to control whether
acquired data are currently written to a file. Clicking on the Press to Start a New Data File
button will start a new data file, and the name of this file will appear in the Data File field
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on the SPIN Tab. To the right of these buttons and switches, the screen displays the current
date and time.
For more information on the SPIN program’s architecture, see Appendix B.
3.1
Getting Help from Within the Software
Context-sensitive help is available for many SPIN features. To access help, press CTRL-H and
hover the cursor over the area in question.
In addition, there are help sections on the Config tab. These sections explain the functions of
the various parameters.
3.2
About Sequences
A powerful feature of SPIN 4.0 is the ability for users to define Sequences. Sequences are sets
of actions the user creates and the software then performs automatically, much like macros
in Microsoft programs. Sequences can be created on the Config > Sequences tab or in the
Sequence Editor or Auto Sampler Sequence Generator in the Utilities menu item. After
sequences have been defined and configured, the user will need to restart the program for
these changes to take effect. Users can then start and stop sequences using the Control tab.
Keep in mind that the state of a Sequence is logically different than the state of the subsystem that it controls. Take the example of a Sequence that turns a series of pumps on
through a set of timed steps. While this Sequence is running, the pumps are turning on,
speeding up to their nominal rate, etc. When the Sequence finishes, the Sequence will be off,
but the pumps will be On. Do not confuse the state of the Sequence with the state of the
subsystem it is controlling.
Also note that stopping a Sequence that is running is different than undoing the things that
the sequence did. For example, consider a Sequence that steps the laser power through a
series of levels at defined time intervals. If this Sequence is written correctly, when it
finishes, it will have left the laser power at a known level. However, if the Sequence is
running and the operator stops the Sequence, the laser power will be left at whatever value it
currently has.
3.2.1
About Exit Steps
One way around the laser-power issue described in the previous paragraph would be to use
the Exit Step feature of Sequences. The purpose of an Exit Stepis to specifya step that should
be taken whenever a sequence ends. In this case, the user could define an Exit Step that
logically undoes the action that the Sequence did. The Exit Step could set the laser to a
specific power level, thus undoing the last power level set by the Sequence. No matter how
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the Sequence finishes or is interrupted, the laser will then be at a known power level when
the Sequence is no longer running.
Note that Exit Steps will execute if the sequence has finished or if the user stops the
sequence using a button on the Control tab. They do not execute if the sequence was
stopped because the program was quit or restarted.
3.2.2
Running Sequences Concurrently
In general, sequences can be run concurrently. However, if multiple sequences act on the
same objects, they generally should not be run at the same time.
3.3
Changing and Saving Configuration Files
Information on the Config tab is intended for reference only. Do not change the configuration
without first contacting DMT, as changing the configuration can cause the system to
malfunction. You will need to log in with a password on the Status tab before Configtabfields
are editable.
To change a configuration file, click on the Config tab. Then click on Load a File. Select the
configuration (*.ini) file you would like to load. If you would like to designate this file as the one
the program uses upon start-up, click Mark Current Config as the Start-up Config. Otherwise, the
next time you restart the program, the configuration will revert to the default start-up.
To save changes you have made to the SPIN program configuration, click on Save Config As… and
then designate a name for the configuration file. This file that was saved will now be shown as the
“Config File Being Viewed.” If you would like this file to be used every time the program starts up,
click Mark Current Config File as the Start-up Config. Note that the program will not use any new
configuration values until it is restarted.
3.4
Creating User-Defined Calculations
The SPIN software provides two ways for users to define calculations for use within the
program. For relatively simple operations, users can define their own calculated channels as
described in section 3.4.1. For more complex operations, users can import LabVIEW routines
for use within the program as described in section 3.4.2.
3.4.1
Creating Calculated Channels
Suppose you want to create a channel that returns the average of Cold Bottom Temp (C)and
Cold Mid Bottom Temp (C). You might do so by following the steps below:
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1.)
2.)
3.)
4.)
Click on Config > Calculations.
Click on the top green button in the Insertcolumn.
Under Calculated Channels, in the Name field, type “Avg Cold Bottom Temp (C)”.
In the Formula box, type the following text:
(Cold Bottom Temp (C) + Cold Mid Bottom Temp (C))/2
5.) Click Save Changes.
6.) Click Restart Program.
7.) Go to the Control tab. If you scroll down to the bottom of the housekeeping channels,
you should be able to see the Avg Cold Bottom Temp (C) channel.
Appendix G lists all the functions available for use in calculated channels.
3.4.2
Using Pre-defined, LabVIEW-based Calculations
The SPIN program allows users to import LabVIEW routines for use within the program. The
following steps describe how to import SPIN software’s built-in “3 Loop Calculator” function.
This function is used to calculate eight outputs from five set-point and temperature channels.
The outputs are useful in controlling the refrigeration valves.
1.) Click on Config > Calculations.
2.) You should see 3 Loop Calculator.vi listed under “Available Calculations.” (If
for some reason the vi is stored other than the default directory, move it into the
C:\DMT\SPIN Support\Calculationsdirectory.)
3.) Double-click on 3 Loop Calculator.vi.It should appear in “Defined Calculations.”
4.) With 3 Loop Calculator.vi still highlighted, click on the first gray box listed
under “Input Channels,” and select Warm SetPoint.
5.) For the following four boxes in the “Input Channels” array, select the following input
channels:
 Avg Warm Temp (C)
 Cold SetPoint
 Avg Cold Top Temp (C)
 Avg Cold Bot Temp (C)
6.) Under output channels, name the output channels as follows:
 Warm On Time (s)
 Warm Off Time (s)
 Cold Top On Time (s)
 Cold Top Off Time (s)
 Cold Bot On Time (s)
 Cold Bot Off Time (s)
 Warm Plate Blue Indicator
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 Cold Plate Blue Indicator
7.) Click on Save Changes in the upper right.
8.) Click on Restart Program in the upper right.
9.) Go to the Control tab. The new channel should be visible at the bottom of the
housekeeping channels on the right. You may need to scroll down to see it.
3.4.3
User-created LabVIEW Calculations
In addition to using the calculation routines provided by DMT, if you have a copy of LabVIEW
2010 you can create new calculations. To do this, open one of the existing calculation VI’s in
LabVIEW as a starting point. Edit the calculation VI and give it a new name. Put the resulting
new VI and all necessary sub-VI’s in the C:\DMT\SPIN Support\Calculations directory.
When the SPIN program is restarted, the new calculation VI will appear in the Available
Calculations list. You can then move it to “Defined Calculations” and specify input and output
channels as described in section 3.4.2.
Note that for operator-created calculations to function correctly in the SPIN program, you
must not alter the interface to the calculation VI. E.g., the new calculation VI must have the
same connector pane with the same data types. Its overall function must be similar, with the
data being indexed the same way and producing the same sort of array of output data with
the new calculations added to the input data array. You should also fill in the Description
text box with relevant text, and then make this text the default for the Description text box.
3.5
Creating and Editing Sequences
The SPIN software allows you to create and editing Sequences on the Config > Sequences
tab. For information on what sequences do, see section 3.2.
Example: Say you would like to edit the “Start Compressors” sequence so it waits two minutes
rather than one after turning on the Cold Compressors. You would do this as follows:
1.)
2.)
3.)
4.)
Click on Config > Sequences.
Under Sequences, click on the Sequence you’d like to edit, i.e. “Start Compressors.”
Click on the step you would like to edit, i.e., “Wait 1 Min.”
In the Sequence Step parameter box, change the Value to 120 (120 seconds, or two
minutes). Change the Label to “Wait 2 Mins.” See Figure 13.
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Figure 13: Modifying the "Start Compressors" Sequence
5.) Click on Save Changes.
6.) Click on Restart Program.
When you click on the Sequences tab in the main SPIN window, you will see the modified
sequence.
4.0
4.1
Starting up the System
Overview
The SPIN must be started up in the following general order. For step-by-step instructions, see
section 4.3.
1.) Install the Detector, flow plumbing and cables with power off.
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2.) Refrigeratethe warm and cold plates to their set-point temperatures (-15 ºC and -15
ºC, respectively).
3.) Pump water into SPIN to coat interior with black ice with the outlet valve in the “fill”
position.
4.) Drainand purge excess water from SPIN to prevent damage to detector box.
5.) Move the outlet valve to the “sample” position and enable the detector.
6.) Start the Sheath flow (10 l/min).
7.) Start the Sample flow (1 l/min) and perform a zero-count test.
8.) Move the inlet valveto the “inlet” position.
4.2
Changing the Inlet and Outlet Valve Positions
The SPIN has both an inlet valve (Figure 6) and an outlet valve (Figure 10). These valves are
controlled by actuators with black knobs (Figure 6 and Figure 10). These knobs can be either
manually manipulated by the user or controlled by the SPIN software. However, within 45
seconds the knobs will revert to the position specified by the software. Thus, while it is
fastest to turn the knob manually, if you do so you will need to remember to change the
software settings as well. These settings are found on the Control tab of the SPIN software
under the digital outputs Inlet Valve Zero/Inlet and Outlet Valve Sample Fill, respectively.
See Figure 14.
`
Figure 14: SPIN Software Controls for the Inlet and Outlet Valves
4.3
Step-by-Step Instructions
Note: The three-way valves on the SPIN are slow-acting valves with a 90-second activation. In
addition, some sequences take several minutes to complete. As a result, it takes a while from
the time the SPIN is turned on until it is ready to detect particles. To avoid damaging the
unit, make sure all necessary preconditions noted below are met before proceeding with the
next instruction.
For a graphic of what the front-panel LEDs indicate about the SPIN status, see Figure 11.
1.) Install the detector under the Outlet valve by angling the detector into place and
rotating the base into position. See Figure 10. Lift the black detector body into
position (on sliders) and connect the inlet of the detector to the outlet valve using the
Swagelok coupler. Connect the air flow return tubing to the bottom of the detector.
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Connect the RS-422 and Detector power cables to the left side of the detector. CHECK
OUTLET VALVE POSITION. The black knob on actuator should be HORIZONTAL,
which is in the FILL position.
2.) Turn on the instrument by flipping all switches on the front panel (Figure 15) to the UP
position.
Figure 15: SPIN Front Panel Switches
3.)
4.)
5.)
6.)
Turn on the computer.
Double-click on the SPIN icon on the desktop.
When the program opens, click on the Control tab.
Click on the Start Compressors sequence button.The digital output switches for Warm
CMP Enable, Cold1 CMP Enable and Cold2 CMP Enable should switch on, indicating
PID control has started for all zones. The Cold2 CMP Enableswitch will turn on
approximately 30 seconds after the other two.
7.) Monitor theWarm and Cold plate Temp (C) (see the Compressor tab on software).
When all Warm and Cold plate temperatures have leveled out around -15C,CHECK
OUTLET VALVE ACTUATOR POSITION. It should be in the fill position with the black
knob horizontal.
8.) Click on the Fill/Empty Sequence. The fill pump should start pulling water from the
reservoir until the water reaches the liquid level sensors 1and 2 (top of chamber). The
pump should stop for the dwell time (typical 5 sec.= 1mm coating). The sequence will
then reverse the pump direction and the chamber will start to empty. Bubbles will be
visible in the water reservoir when the chamber is empty and the front panel Status
LED red should go out.
9.) Take note if there is any water in the lines connected to the chamber outlet. If there
is some remaining water, or the Status LED is still red, the Purge Sample tube
sequence can be run to drive the water out of the lines.
10.) Switch on the Outlet Valve digital output (on the Control tab in the software) to
move the valve to the "sample" position. The front panel Sample LED will turn blue.
The valve actuator takes about 45 seconds to achieve the correct position with the
black knob vertical.
11.) On the software’s Control tab, click on the Open Detector Com Port button. This
will open the COM port, send an initialization command, and start data
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communication. If the port is not enabled, unplug the RS-422 USB connector, plug it
back in, and click again on the Open Detector Com Port button. The Detector
Controller indicator in the software should turn green and read Enabled.
12.) The laser will be set to the default setting listed on the Config > Acquisition tab. If
the laser is off, turn it on using the Laser Controlon the Control tab.
13.) Staying on the Control tab, click on the Set Sheath Flow sequence button. The
sheath flow can be monitored on the bottom graph of the SPIN tab.
14.) On the Control tab, click on the Set Sample Flow sequence button. The sample
pump should come on and the front panel Zero LED should be green.
15.) The Inlet ValveActuator (Figure 6) should be in the default position “Zero” (the
black knob of the inlet actuator is horizontal). On the SPIN tab in the software, check
the middle graph to ensure particle counts are near zero.
16.) In the software, switch on the Inlet Valve Inlet/Zerodigital output to move the valve
to the "inlet" position. The front panel Status LED will turn blue After 45 seconds, the
system should be sampling particles that are applied to the inlet.
5.0
1.)
2.)
3.)
4.)
5.)
6.)
7.)
8.)
Shutting Down the System
Shut off sample flow by navigating to the Control tab in the software and switching the
Sample Pump digital output to the off position The green LED on the front panel labeled
Zero should turn off.
Shut off sheath flow by switching the Sheath Pumpdigital output (on the Control tab) to
the off position.
Switch the Inlet Valve Inlet/Zerodigital outputto the "filter" position (off).The front
panel Status blue LED should go off. Wait for 45 seconds, or manually push in the Inlet
Valve Actuatorblack knob and rotate to the horizontal position. Note: if the Inlet Valve
Inlet/Zero digital output has not been switched to off as described above, the Inlet
Valve Actuator will slowly return to the position controlled by the computer.
Switch Outlet Valve Sample/Fillto the "fill" position (off). The front panel Sample LED
blue should go off and the Outlet Valve Actuator black knob will rotate to the horizontal
position (fill).
On the Control tab of the SPIN software, click on the Stop Compressors sequence
button. Switch any digital output toggles that are on to their “off” position.
Shut down the SPIN software and the laptop. Turn off the AC Main power.
Disconnect the RS-422, Detector Power cable and the Detector outlet tubing from the
detector. Detach the detector inlet Swagelok connection from the outlet valve. Rotate
the bottom of the detector box and remove the box to avoid possible water damage from
the melting chamber ice.
Connect the water flow to the reservoir to prepare for warm-up and drying the chamber:
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9.)
a. Disconnect the Outlet Valve Actuator and sample tube by disconnecting the
Swagelok from the base of the Sample tube tee and withdrawing the sample tube
(3-4 inches). See “Sample Tube Removed from Chamber” in Figure 16.
b. Connect the tubing provided with the water reservoir to the bottom of the tee.This
tubing is labeled “Channel Water Return Tubing” in Figure 16.
c. Remove the reservoir from its position on the left side of the rack. Position the
reservoir under the tee, with the connected tubing to the tee in the reservoir.See
Figure 16.
Start the external sheath flow for drying chamber:
a. Disconnect the cap at the rear of the chamber connected to the sheath inlet.
b. Connect an external, user-supplied pump to the external sheath connection (Figure
17).
c. Start a flow of 10 -15 liters / minute. The flow should run through the chamber and
bubbles should be visible in the reservoir container.
d. Leave the system in this configuration overnight to melt the ice and dry the chamber.
Figure 16: Chamber Water Return Configured for Drying Chamber
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Figure 17: The SPIN Configured with an External Pump for Drying the Chamber
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6.0
Ice Nuclei Chamber
As noted above, the SPIN cools the ice nuclei chamber via two refrigerated plates. These
plates run lengthwise along the back side of the SPIN. The exterior plate is the Warm
Refrigeration Plate, which is typically kept at -40 ºC. This plate has one temperature zone
and two PID control loops to regulate its temperature. The interior plate is the Cold
Refrigeration Plate, which has four temperature zones and four PID control loops.
Figure 18: Conceptual Diagram of Ice Nuclei Chamber
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6.1.1
Cooling Loops
Cooling loops are used to distribute refrigerant to specific areas each plate. The warm plate
contains one valve and two loops (Figure 19), while the cold plate contains four valves and
four loops. Capillaries determine how much refrigerant gets fed into the cooling loops.
Capillary
Loop 1
Solenoid Valve
Capillary
Loop 2
Figure 19: Conceptual Drawing of Refrigerant Loops (Not to Scale)
6.1.2
Refrigerant Compressors
There is one compressor that cools the warm plate and two that cool the cold plate. The first
cold-plate compressor is a closed loop and does not feed refrigerant directly to the plate;
rather, it precools the refrigerant of the second compressor.
6.1.3
Icing the Chamber
The thickness of the ice coating on the ice nuclei chamber is determined by how long water
sits in the chamber before being emptied. If you are using the Fill/Empty Chamber sequence,
the Ice Dwell Counter parameter determines how long the chamber will remain filled before
emptying. By default, the Ice Dwell Counter is set to 5 seconds. This setting results in the ice
nuclei chamber being coated with approximately 1 mm of ice.
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7.0
7.1
Optical Particle Counter (OPC)
Optics
The OPC is located in the SPIN detector box at the bottom of the instrument. The OPC uses
four detectors for counting, sizing and classifying the particles as liquid or ice. Particles
approximately in the 1 - 20 µm range are sized.
Figure 20details the optical diagram. The sample inlet can be viewed as going into the page
at the intersection of the red laser beam and the green and blue light rays (i.e., along the xaxis).
Figure 20: SPIN Optical Diagram
The source laser is 500 mw, 670 nm laser with a top-hat beam profile. This type of laser
illuminates the entire sample area with a high degree of uniformity, eliminating the need for
a qualifying detector. The source laser is linearly polarized for the polarization discrimination
in the backscatter.
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The particle counting and sizing is done with side-scattered light using the Mangin mirror pair.
The collection Mangin next to the jet/laser intersection collects the light and sends it to the
detectionMangin where it focuses on the sizing detector.
There are two sets of optics for backscatter light collection. In Figure 20, the green rays are
passing through the first set of optics, which can be envisioned as coming out of the plane of
the page. This set has a polarizing beam splitter and is the primary unit for determination of
the polarization change. It provides both P and S polarizations (P1 and S1). The second set of
backscatter optics is not visible in Figure 20. It measures just the P polarization (P2). The
detection angle is centered at 135º and has a half angle of 20º.
Figure 21 illustrates all the detectors in the Detector Box—side-scatter, S1 and P1 (from the
first set of backscatter optics), and P2 (from the second set).
Figure 21: Optics in Detector Box
7.2
Amplification of Particle Signals
Each of the four OPC detectors (sizing detector, S1, P1 and P2) feeds its signals in to
electronics that amplify the response. See Figure 22.
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Figure 22: Signal-Amplification Electronics
The dual-gain approach provides for more dynamic range in the measurement. The processing
electronics continuously monitor the output of the high-gain amplifier, and if this saturates
(i.e., goes off scale), the signal from the low gain A/D converter is monitored. Once the
scattering signal peak has been detected, this value is recorded with information on the gain
stage where it was collected. The A/D converters are 12 bit with a count range up to 4096
counts. The high-gain amplifier has a gain of 10 over the low gain amplifier.
While the dual-gain system improves the SPIN’s measurement capabilities, it also means that
signals from one detector cannot automatically be compared to those from another. For
instance, you cannot divide a particle’s raw side-scattering signal by its raw backscatter 1
signal to obtain a valid side:back1 ratio, since one measurement may have been made with a
low-gain amplifier and another with the high-gain. The following section of this manual
describes how to adjust the data to account for the different signal-amplification levels.
7.3
Data Analysis with the PbP File—Correcting for Different
Amplification Levels
The data from the OPC is recorded in two files. One file is named SPIN
YYYYMMDDHHMMSS.csv, where YYYYMMDDHHMMSS is a time stamp. This file contains the
housekeeping data and the basic sizing and counts data; for information on specific channels
in this file, see Appendix C. The other file is named SPINPBP YYYYMMDDHHMMSS.csv. It
contains the data in a Particle-by-Particle format where the peak signals from the individual
detectors along with the time stamp are recorded. This data is the most useful for analysis if
the particles are liquid or ice at the detector.
The data file for the PBP contains five columns, shown on the following page.
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Time Stamp
32465.97964
32469.48084
32469.48084
32469.48084
32469.48084
32469.48084
32469.48084
32469.48084
32469.48084
32469.48084
32469.48084
32469.48084
32469.48084
32469.48084
Size P2 [Counts]
44
0
55
0
140
0
153
212
0
37
36
0
0
0
95
0
163
0
190
0
221
7
145
0
166
337
146
0
S1 [Counts]
0
234
0
758
0
0
907
779
923
0
371
884
0
774
P1 [Counts]
0
0
203
618
0
641
0
0
0
657
0
0
648
0
The first column is the time stamp of the data recording. This time does not increment with
each particle, but is the time the data is acquired from the electronics buffer. This is at the
basic sampling rate of 1 Hz. The other four columns are the peak height from the detectors in
Analog to Digital (A/D) counts.
The signals for each of the detectors can be directly correlated when all four signal counts
are less than 4096. Data with a signal count over 4096 have a different amplification
level,however, and these data must be “spliced” to the lower-signal data. (See section 7.2
for a discussion of the amplification electronics.) If the splicing adjustment is not done, the
data will show a gap like that in Figure 23.
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Figure 23: Raw Data Counts for Limonene Droplets
In theory, the data can be corrected by using the following equation:
Corrected counts= ((data counts greater than 4096)-4096) * 10
(Y)
In practice, however, each of the four detectors requires a slightly different subtraction value
to optimize the continuity of the data. This variation is due to slight offsets in the
electronics. The presently recommended values for subtraction are:
Size = 4073
P2 = 3987
S1 = 4040
P1 = 4004
Figure 24shows the results of applying this correction to the data inFigure 23.
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Figure 24: Data in Previous FigureCorrected for Amplifier Gain
Note that the total signal range is expanded.
The goal in the signal correction for equation Y is to have neither a gap in the data nor a high
concentration of particles at 4096 counts. In the data shown inFigure 24, the correction in the
X axis, for sizing/side-scatter counts, is quite good. The data are very continuous. In the Y
axis, there is a slight gap in the data, indicating that the magnitude of the subtracted counts
is slightly too low and a larger number should be used. The correct value for subtraction can
be easily determined by analyzing the data in scatter plot format as inFigure 24. In this case,
it is recommended that the subtracted value be increased by 5 to 10 counts.
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7.3.1
Depolarization Data Analysis
Spherical particles retain the polarization of the scattered light, while aspherical particles
will scramble that polarization. It is this behavior that will be exploited to separate the ice
and water droplets at the exit of the SPIN chamber. A full review of analysis options has not
been completed. A recommended starting point is the ratio of the S1 to P1 polarization.
Figure 25 shows this ratio for limonene as a function of side scatter signal.
Figure 25: Scatter Plot of the S1/P1
Backscatter Ratio as a Function of Droplet Size in A/D Counts
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One of the limiting factors in the analysis of the SPIN PBP data is the lack of standards which
can be used as calibration materials for uniformly aspherical particles. This makes it
important to critically examine results from empirical data. Figure 26 shows an analysis of the
S1/P1 ratio as a function of particle size for volcanic ash collected from the Iceland volcano.
Figure 26: S1/P1 Polarization of Volcanic Ash
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A comparison of this data with Figure 25 shows that the ratios are on the average much higher
than that for limonene. The P1 polarization signal, which is the same polarization as the
incident laser, is reduced. The S1 polarization signal, which comes from the scrambling of the
incident light, is enhanced. This is the expected result, since ash particles are generally
aspherical.
Figure 27 details the same type of polarization ratio analysis for water droplets, aspirated
into the SPIN OPC directly in a separate experiment.
Figure 27: S1 / P1Polarization Ratio for Water Droplets
For the very small droplets, there will be considerable scatter in the data as the backscatter
signal is approximately 1/10 of the sidescatter signal and the uncertainly in the data is large.
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There is a trend of increasing S1 /P1 ratio in this data with increasing particle size, and this is
not understood and warrants further research.
It is recommended that the user evaluate all of the scattering data, and working with known
materials in the SPIN, try to optimize use of the polarization data to separate the water
droplets and ice crystals in the OPC.
8.0
8.1
SPIN Software Tabs
SPIN Tab
The SPIN tab is shown inFigure 28.
Figure 28: SPIN Tab
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Data File displays the file to which output data are currently written. Typically this file is
named C:\DMT\SPIN Data\YYYYMMDD\YYYYMMDDhhmmss.csv, where YYYYMMDDhhmmss
is the date and time stamp.
Alarm Note shows a log of alarm notes. Alarm notes are a subset of the data file log that lists
especially important events. The user can select events to appear in the Alarm Notes by
creating an “Alert” action on the Alarms and Timers sub-tab of the Config tab.
The histogram on the left side of the display shows particle counts for the current moment in
time.
The two or three charts on the right-hand side of the SPIN Tab show user-selected
housekeeping channels. Each chart shows two channels, one in blue (with its scale on the left
y-axis) and one in red (with its scale on the right y-axis). The names of the channels appear in
the white boxes above each graph. The channels can be changed in two ways: by rightclicking on the boxes and selecting a new channel from the drop-down list, or by using the
arrows to the left of the boxes. Values for the current moment in time appear in the relevantcolored box above each time-series chart.
The user can control how far back the charts display data by clicking on the time control
above the top graph (Figure 29).
Figure 29: Control for Determining the Time Range of Displayed Data
Clicking on Press to Pause Display freezes the data display to the current moment in time.
8.2
Control Tab
Figure 30 shows the Control tab, which displays information about temperature and flow
controllers, sequences, and housekeeping channels.
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Figure 30: Control Tab
8.2.1
Controller Channels
Controller channels and their set points are displayed in the upper left corner of the tab.
Users can modify these set points by typing new values directly into the corresponding fields,
or by using the up-and-down arrows to the right of the fields. If no Controllers have been
created, this section will be blank.
8.2.2
Sequence Switches
If the current configuration has any Sequences defined, and these Sequences have been
created with switches, then a set of Sequence Switches will be displayed on the left side of
the Control tab. The Sequence Switches display the available sequences and allow the user to
start and stop these sequences. The user can start a sequence by clicking on the relevant
button, which will then turn green and indicate that the sequence is running (Figure 31).
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Figure 31: Control Tab while “Compressors Starting” Sequence is Running
Keep in mind that stopping a Sequence that is running is different than undoing the things
that the sequence did. See section3.2for more information.
Sequences are stored as an array. If more sequences are available than can be displayed at
one time, the scroll bar allows users to change the range of sequences that is displayed.
The table below lists the default SPIN sequences, their purpose, and when they are used.
Name
Start Compressors
What Sequence Does
When Used
Starts warm-plate and cold-plate Before the chamber is filled and
compressors at a rate of 3000 RPM. iced.
These compressors pump refrigerant
through the chamber walls.
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Stops the warm-plate and cold-plate  When the sample inlet has
compressors.
iced over
 When the sampling session is
complete
Empty Chamber
Empties the chamber of excess  After the chamber has been
water (opens valve repeatedly until
filled and iced
Liquid Level3 is zero, meaning no  When the STATUS light is
water
is
detected
at
this
red, indicating water is
checkpoint)
pooling above the optical
detector
Purge Sample Tube
Shoots air up through the sample When the STATUS light is red,
tube to clear it of excess water. indicating water is pooling
Purge continues until there is no above the optical detector.
excess water at Liquid Level3.*
Set Sheath Flow
Sets the Sheath Flow set point to 10
LPM (2.5 V).
When the chamber has been
Set Sample Flow
Sets the Sample Flow set point to 1 iced.
LPM (0.25 V).
Fill/Empty Chamber Fills, empties and purges the SPIN When the SPIN is first turned
chamber so that it ices over. This on, after the compressors have
sequence
combines
the
Fill been started.
Chamber, Empty Chamber and Purge
Sample Tube sequences in a logical
order.
Aerosol Controller IV Sets
warm
and
cold
plate When the user wants to change
temperatures according to values the aerosol temperature.
specified by Aerosol Target (C) and
Delta Target (C). Example: say the
Aerosol Target is -20 ˚C and both
the
warm
and
cold
plate
temperatures are -20 ˚C. If the user
sets Delta Target (C) to 20 and
Aerosol Target (C) to -30 ˚C, the
warm plate will stay at -20 ˚C while
the cold plate will move to -40 ˚C.
See Appendix K for more details.
Stop Compressors
* For a more detailed explanation of the Purge Sample Tube sequence, see section 2.4.2.
8.2.3
Digital Outputs
The Digital Outputs column lists digital outputs that are defined within the SPIN. Any number
of such channels can be defined using any National Instruments devices that support them.
Users can define digital output channels on the Config > Digital I/O tab.
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8.2.4
Channels
The gray fields on the right side of the screen provide current values for the housekeeping
channels. The ordering of these channels can be changed within the Config tab. See section8.6.2
for details.
8.2.5
Detector Controller
The Detector Controller channels control the state of the optical particle counter (OPC). Once
the SPIN is properly cooled and ready to begin counting nuclei, the user should click Open
Detector Com Port. This will open the COM port, send an initialization command, and start
data communication. The Disabled indicator should then turn green and read Enabled. If the
laser is off, it can be turned on using the Laser Control.
8.2.6
Alicat Flow Controller
theAlicat Flow Controller box allows the user to determine the controller’s set point. The set
point can be changed by entering a new value in the white field and then clicking on Set New
Value. The gray field indicates the current set point.
8.2.7
“Set Any Output Channel Here”
This field allows users to set the value of specific output (control) channels. For example, setting
Sheath Flow Set (vccm) to 800 will result in changing the Sheath Flow Set (vccm) channel to 800.
Only output (control) channels can be set with this feature.Once a channel and value have been
specified, click on Set Channel to have these settings take effect.
8.3
Status Tab
The Status tab (Figure 32) provides information about the program’s status.
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Figure 32: Status Tab
The Data Folder and Data File fields show the locations where the SPIN output data are stored.
These settings cannot be changed from this screen; rather, changes must be made to the Config
tab settings.
Configuration File lists the configuration file the SPIN software is currently running.
Description lists the description associated with this configuration file, if one exists. Users can add
descriptions to configuration files on the Configuration > Program tab. Note that changes to the
configuration will not take effect until the program is restarted.
Serial Numberliststhe serial number of the SPIN.This serial number is read directly from the green
SPIN USB key.
Versionlists the current version of the SPIN software.
The right side of the tab displays information about alarms that the program is currently testing
for.Alarms are stored as an array, and if more Alarms are defined than can be displayed at one
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time, the scroll bar allows users to change the range of Alarms that is displayed. For each alarm,
the tab shows the following information:




Alarm name
The “Condition” or alarm status—False, Warning, or True. If the status is false, i.e. the
alarm hasn’t been activated, the indicator square will be green
The time at which the warning or alarm conditions were first met, if applicable.
The condition trigger for the alarm (the current value of the channel that triggered the
alarm, the operand used in testing the alarm condition, and the threshold). For more
information about alarms, see section8.6.6
Note that additional parameters such as Hysteresis and Min Time also influence whether an Alarm
is True or False. These parameters are not displayed on the Status tab, but you can view them on
the Config > Alarms and Timers tab.
If any alarms are in a Warning state but none are True, the Alarm Status button at the top of the
program display turns yellow.If any alarms are True, the Alarm Status button turns red.
The lower portion of the Status tab displays the 20 most recent events and errors that the program
has logged. Although only 10 logs are shown at once, the scroll bar to the right can be used to view
the remaining 10 logs that are available.These events and errors are stored in the *.log file. Users
can also add their own notes to this file by typing text in the Message field and clicking the Log
This Message button.
8.4
Sequences Tab
Figure 33 shows the Sequences tab. Note that if no sequences are defined, the Sequences tab is
not visible.
As explained above, Sequences are sets of actions the user creates and the software then
performs automatically. See section3.2 for details.
The sequences tab displays all available sequences. The sequence tab also allows users to activate
sequences, by clicking on the
button. When the sequence is running, the button will
light up, and the Step and Timer parameters will update.If the button is pressed while the
sequence is already running, the sequence will be stopped.
To view more sequences, use the horizontal scrollbar at the bottom of the screen. To view a full
list of steps in a sequence, use the vertical scrollbar to the right.
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Figure 33: Sequences Tab
Sequence steps are listed in order beneath each sequence. To get more information on a particular
step, hover the cursor over it. A box will appear in the right margin with additional information.
Note that Exit steps are not listed, as they are not technically part of the sequence itself. If exit
steps exist, however, they will get executed whenever the sequence stops. To see the specified
Exit Step for any Sequence, view that sequence in the Config > Sequences tab.
To modify sequences, go to the Config > Sequences tab.Changes made to sequences do not take
effect until the program is restarted.
8.5
Custom Tab (Optional)
If you have configured a custom tab on the Config > Custom sub-tab, it will appear between
the Sequences and Config tabs. The name of this tab and its appearanceare determined by
the parameters in the Config > Custom sub-tab.
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8.6
Config Tab
The Config tab is the most extensive of all SPIN tabs. It contains many sub-tabs that allow the
user to view and/or change parameters related to the SPIN instrument and software. It also
allows the user to set specifications for streaming data out to a serial port or Ethernet
connection, or in from an aircraft-navigation system or other data stream via an Ethernet
connection or a serial port.
Information on the Config tab is intended for reference only. Do not change the configuration
without first contacting DMT, as changing the configuration can cause the system to
malfunction. To access the configuration sub-tabs, you must first enter a password on the
Status tab.
Note: After changing any parameters in the configuration tab, you must click on Save
Changes and then Restart Program for the changes to take effect. Save Changes is grayed
out until changes are made.
8.6.1
Program Sub-tab
The Program sub-tab allows the user to set default parameters to manage the SPIN software.
This tab is shown inFigure 34.
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Figure 34: Program Sub-tab
8.6.1.1
Left Side of Screen
Data File Path stores the directory in which data files are stored. The default setting for this
parameter is C:\DMT\SPIN Data. A new path can be entered by typing into the field or by
clicking on the folder icon to the right of the field.
If a valid NTP Server IP address is entered in the NTP Server parameter, the program will
attempt to connect to the NTP server when it first starts. If successful, it will adjust the
computer clock appropriately once before taking data.
If Restart Files at Midnight is selected, the program will automatically create a new folder
and new files at midnight. If Continuous Files is selected, a new file will not be automatically
started at midnight.
The Write File/Don't Write File parameter determines whether or not the program begins
writing data to a file immediately when it starts.
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Control Cycle Time specifies an interval in milliseconds for the program’s control loop. See
Appendix B for information on the control loop. The default rate is 1000 msec (1 second).
Time Range determines how much data is displayed in the time-series graphs when the program
starts. This value can be changed by the user after the program is running.
Graph Backgrounds controls the background color of all graphs on the SPINtab. Clicking on
the square will bring up a selection of color options to choose from.
Two Graphs/Three Graphs allows the user to select whether the SPIN tab should display two
or three user-selectable time-series graphs. Each graph displays two channels, one with the
axis on the left and one on the right.
The OSDS Format is an optional feature for reading streaming data from a variety of sources. If
this field is blank, no data are streamed in. Configuration of this feature is complex and you should
consult DMT before using it; see the Communication tab for more information.
Description allows the user to enter a description of the current configuration file.
Serial Number displays the SPIN serial number. This number cannot be changed by the user.
The boxed Upper Graph, Lower Graph, and Third Graph (optional)controls specify which
channels are graphed in the time-series graphs upon start-up. To change the channels, use
the arrow controls or click on the channel name to bring up a list of options.
Clicking on the Reset to Defaults button restores all the values on the Program tab to their
DMT-supplied defaults. Note that you must save these changes and restart the program to
have these defaults take effect, just as you would do for any other changes.
8.6.1.2
Controls for Shut Down Sequence and Emergency Shut Down Sequence
Beneath the help window are two drop-down boxes that govern what actions the SPIN takes
upon shut down. The sequence selected in Shut Down Sequence will execute any time the
SPIN shuts down normally—for example, when the user clicks the close button in the upper
right corner of the SPIN window, or when the user selects File > Exit. The sequence selected
in Emergency Shut Down Sequence executes whenever the SPIN has an emergency shut
down. An emergency shut down occurs when the user clicks the exclamation point icon
from any SPIN window.
Note on Shut-Down Sequences: Because the user must restart the SPIN software in order for
configuration changes to take effect, any sequence listed in Shut Down Sequence will
execute when configuration changes are saved.
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8.6.1.3
Right Side of Screen
The right-hand side of the screen provides options for handling configuration files. If you only
use one configuration for your system, you will not need to use these controls very often.
When you make changes, you can simply click on Save Changes and Restart Program, which
will update all program settings to the ones selected on the Config sub-tabs. These settings
will also be used the next time the software loads.
Pressing Save Changes writes the current configuration data to the configuration file shown in
the Config File Being Viewed indicator. This file is stored in the C:\DMT\SPIN Support
directory.
Pressing Restart Program causes the SPIN program to restart, loading the currently defined
Start-up Config File.This is a quick way to make configuration changes take effect. Note that
when the program is restarted, time-series graphs will lose their history and a new data file
will be opened.
Config File Being Viewed displays the name of the configuration file that was last read from
or written to. If you have edited the configuration parameters, the currently displayed
configuration parameters will not coincide exactly with those in the file or with those the
program is actually using.
Start-up Config File displays the name of the configuration file that will be used the next
time the SPIN program is started. This file is stored in the C:\DMT\SPIN Support
directory.
Press the Mark Current Config File as the Start-up Config to designate the Config File Being
Viewed as the Start-up Config File.The parameters in that file will be used the next time the
program starts.
Save Config As...saves the current configuration parameters to a file with a name chosen by
the operator.This allows you to save various configurations for future use or reference. Note
that you can only archive configuration files to the C:\DMT\SPIN Support directory.
Load a File loads the configuration parameters stored in any previously saved configuration
file into this editor. These new parameters will NOT be used by the program unless they are
saved to the file that is designated as the Active Config File.
Load Start-up Config will load the start-up configuration file. The name of the start-up
configuration file is shown in the Start-upConfig File indicator. To change the start-up
configuration file, use Load a File to load the desired file, then press Mark Current Config
File as the Start-up Config.
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8.6.2
Acquisition Sub-tab
The Acquisition sub-tab allows the user to set and view parameters related to data acquisition. It
also determines which data channels are acquired and which are displayed on the SPIN data graph
on the SPIN tab.
The Acquisition tab is pictured inFigure 35.The parameters visible on the tab are described
below.Note that this tab is still under development and will contain additional parameters in the
future.
Detector
Parameters
Threshold
Tables
Conversion
Equations
Figure 35: Acquisition Sub-tab
8.6.2.1
Detector Parameters
Com Port lists the communications port for the SPINdetector signals. Baud Rate lists the baud
rate, and Channel Count lists the number of sizing bins on the SPIN.
The PbP Threshold parameters (Size Thresh, P2 Thresh, etc.) list minimum digital counts for PbP
particles to be classified. Particles are rejected for PBP analysis if they do not meet any of these
criteria.PbP Every N Particles allows the user to filter particles for counting and sizing. If the user
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selects “3,” e.g., only one out of every three detected particles will be sized. Pressing Load
Detector Defaults reverts the Detector Parameters to their default values.
Laser Control determines whether the laser in the OPC is on or off at start-up.
Flow Source allows the user to specify the flow source to be used. Typically this is set to Sample
Flow, but it can also be set to a calculated channel.
8.6.2.2
Threshold Tables
The Threshold tables allow the user to specify sizing bins for the PbP particles. For each bin, the
table lists the upper bin boundary in µm and the upper threshold in digital counts. The lower
boundary and threshold of each bin are the upper boundary and threshold of the previous bin. Bin
1’s lower boundary and threshold are listed at the top of the threshold tables.
You can load pre-existing tables by pressing the Load Tables button, which allows you to navigate
to a file storing the table. Write Tables saves the displayed tables to a file for future use.
8.6.2.3
Conversion Equations
The controls in the bottom left box list the custom conversion equations for each housekeeping
channel. These equations are used to convert digital counts into meaningful units.
8.6.2.4
Channel Order Table
The Channel Order list on the right-hand side of the screen is used to order the housekeeping
channels. This order applies to both the SPIN software (in drop-down lists) and in the *.csv output
file.To substitute a new channel for one already in the list, click on the gray arrows or right-click
on the existing channel’s name. Clicking on the Insert (green) or Delete (red) buttons allows
channels to be inserted or deleted.
The first channel in the Channel Order list is always Time (sec since midnight) and cannot be
changed. Any channels not explicitly included in this list will be added on to end of the channels.
Digits of Prec. affects how the channels are written to the *.csvdata file. To use automatic
formatting, use a value of -1 for Digits of Prec.Any channel in the data file that is not
explicitly listed in the Channel Order will also use automatic formatting. Note: This
parameter does not affect how channels are displayed within the program, which always uses
automatic formatting.
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8.6.2.5
Restoring Parameters to Defaults
The Reset to Defaults button at the bottom of the windowresets all the Acquisition
parameters to their DMT-supplied defaults.
8.6.3
Analog In Sub-Tab
The Analog Input (“Analog In”) sub-tab specifies information about the housekeeping data
acquisition devices. It also allows the user to view and define the method used to convert voltage
readings to meaningful units for the housekeeping channels.
Figure 36: Analog In Sub-tab
8.6.3.1
Lookup Table
Lookup Table is an array that allows one or more analog input channels to be scaled from
voltage to engineering units according to any arbitrary relationship. Any channel which has
the Scaling parameter set to Lookup Table will use this table to scale its value. The program
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will take the channel's voltage and interpolate it into the Raw Value column of the Lookup
Table and use a quadratic fit to the 5 nearest points to calculate the scaled value.
Load Table from Fileallows the user to load a Lookup Table from a preexisting file. The file should
contain two columns of data, raw and scaled, separated by commas or tabs, with no header and
any number of rows.
8.6.3.2
Devices
Single-Ended/Differential defines whether a National Instruments data acquisition device is
configured for Single-Ended or Differential operation. The device must be wired
accordingly.Note that all channels on a given device must be configured and wired the same
way. The NI-9213 TC module ignores this parameter.
8.6.3.3
AI Channels Table
AI Channels is an array that defines conversion methods for the analog-input housekeeping
channels acquired from any number of National Instruments data acquisition devices. To view
different elements in the array, use the numeric control right underneath the “AI Channels”
labelor the scroll bar on the right of the AI Channels array. The number listed in this control
will correspond to the array element shown in the top row of the display table. You can type
numbers directly into the field, or you can use the arrows to increment or decrement the
number.
The channels can be listed in any order. Channel names appear in the first column. The
Scaling column lists the type of scaling used to convert the measured voltage to engineering
units. There are several scaling options:
-
Thermister: a built-in scaling system for SPINThermisters.
YAG Thermistera built-in scaling system for SPIN YAG Thermisters.
Polynomial: a polynomial equation with coefficients specified in the Offset, Linear,
Quadratic, and Cubic columns.
None:no conversion. Data will be returned as a Voltage.
Lookup Table:a scaling system based on a lookup table.See section 8.6.3.1.
The Device column lists the number of the device from which the analog input is read. The
Chan column lists the channel number on this device. The Range column lists the analog
input range. Note that not all of the Range options listed are available on all National
Instruments devices. The range selected must be available on the NI device that is installed
for the measurement to be made correctly.
Channels can be added or removed from the table using the Insert (green) and Delete (red)
buttons to the right of the table columns.
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Reset Channels to Defaults sets the channels back to their DMT-supplied default values.
8.6.4
Digital I/O
The Digital I/O sub-tab (Figure 37) allows the user to configure Counter channels, Digital
Inputs, and Digital Outputs. For each type of object being configured, users can insert or
delete individual objects by clicking on the green and red buttons to the right of the
parameters.
Figure 37: Digital I/O Sub-tab
8.6.4.1
NI 9402 Counters (Boxed Controls in Upper Left)
The SPIN program is designed to use a NI 9402 Digital I/O Device for measuring up to four
motor speeds. The SPIN software allows you to create counter channels (“Counters”) to
measure these pulse frequencies, which are between 500 and 2000 Hz.
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Note on Acquisition Cycle Times: When pulses are present on all the counter channels that
are configured, reading these counters will normally take less than 200 ms.Since the data
acquisition system must also talk to other devices, however, it is best to avoid Acquisition
Cycle Times less than 500 ms (2 Hz). If counter channels are configured that do not have a
pulse signal present on them—e.g., a motor is turned off—the counter acquisition time can
actually increase slightly. When all four counters are configured but none have signals, it may
take 300 ms to acquire the counter data. DMT has measured these benchmark times on one
particular computer, andtimes may vary from system to system. However, an Acquisition
Cycle Time of 500 ms or higher should suffice for most systems.
The Device parameter must exactly match the name given to the NI 9402 Digital I/O Device in
the Measurement and Automation Explorer.
Each of these counter channels can be given a descriptive name in the Channel Name
parameter.
The Coefficient is a number that the frequency in Hz is multiplied by to arrive at the motor
RPM.
# of Averages is a parameter designed to improve the accuracy of motor-speed readings. The
motor RPM signals tend to be quite noisy, and the NI 9402 Counters measure frequency by
measuring the period of a single pair of pulses, rather than by averaging the periods of
multiple pulses. Thus the SPIN program contains a separate loop that continuously polls the
9402 Counters to accumulate a running average over # of Averages samples for each Counter.
Wait Time (ms) is the time period the Counters loop pauses before embarking on another
measurement loop.
Note on Selecting Values for # of Averages and Wait Time (ms):
Each Counter measurement takes about 30 ms, and although the four Counter measurements
are called in parallel, the total time for the loop is cumulative with the number of counters.
Thus a single measurement for all four counters will take about 120 ms. Using # of Averages
of 8 will therefore refresh the averaged value approximately once a second. A higher # of
Averages may be needed to adequately reduce the noise level, however. After each
measurement of the Counters, the Counters loop waits Wait Time (ms) before making
another measurement. Set this to 0 to maximize the measurement rate, or increase this to
throttle the Counter loop to reduce its toll on the CPU.
8.6.4.2
Digital Outputs Parameters
Any number of Digital Output channels can be defined within the SPIN system, using any
National Instruments device that supports them.
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Name defines the name of the digital output channel within the SPIN system. Channel is used
to define the channel number of the digital output bit on the National Instruments hardware.
Port defines the digital port that the digital bit is associated with on the National Instruments
hardware.
Device must match the device name of the National Instruments Digital IO Device as seen in
Measurement and Automation Explorer.
Initial State is used to define the state, On or Off, that the digital bit will be set to when the
SPIN program starts.
Invert?can be used to invert the logical output of the digital bit. If this parameter is set to
“On is True”—i.e., there is no inversion—then when the SPIN switch is set to On, the digital
bit will be True. If set to “On is False,”data are inverted. When the SPIN switch is set to On,
the digital bit will be False.
8.6.4.3
Digital Input Parameters
Any number of Digital Input channels can be defined within the SPIN system, using any
National Instruments device that supports them. Each Digital Input channel is logged in the
SPIN system as another data channel, with a value of 0 representing a low input signal and a
value of 1 representing a high input signal.
Name defines the name of the digital input channel within the SPIN system.
Channel is used to define the channel number of the digital input bit on the National
Instruments hardware.
Port defines the digital port that the digital bit is associated with on the National Instruments
hardware.
Device must match the device name of the National Instruments Digital IO Device as seen in
Measurement and Automation Explorer.
8.6.5
Flow and Control Sub-Tab
The Flow and Control sub-tab governs the flow controllers (left side of screen) and the flow
meters (middle of screen). Unlike other screens, where help windows are always visible, users
must click on the Flow Controller Help and Flow Meter Help buttons to view help windows.
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Figure 38:Config Tab—Flow Sub-Tab
8.6.5.1
Controllers
The Controllers define how analog output voltages are set to control external devices.Often,
these control functions use housekeeping channels as inputs to calculate the desired output
voltage.
The standard Controllers that come configured with the SPIN include the following:
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Controller Name
Warm Cmpr SP (RPM)
Cold 1st Cmpr SP (RPM)
Cold 2nd Cmpr SP (RPM)
Sheath Flow SP (slpm)
Sample Flow SP (slpm)
Warm Setpoint (C)
Cold SetPoint (C)
Controller Type
Direct SetPoint
Direct SetPoint
Direct SetPoint
Direct SetPoint
Direct SetPoint
Manual
Manual
New Channel Name
Warm Compr (V)
Cold 1st Compr (V)
Cold 2nd Compr (V)
N/A
N/A
N/A
N/A
In addition to the default Controllers described above, the Controllers parameters allow the
configuration of an arbitrary number of Analog Output control channels.Each channel can be
configured to be one of the following types:







Direct Setpoint: Used to create an Analog Output channel that has a voltage SetPoint
that the operator controls directly.This can be used with a Mass Flow Controller for
which the operator Set Point is also in Mass Flow, a Volume Flow Controller for which
the operator Set Point is also in Volume Flow, or other controls that need an Analog
Output voltage directly determined by an operator SetPoint.
Mass Controller, Volume SP: Used with a Mass Flow Controller for which the operator
Set Point is in Volume Flow. A second data channel will be created to record the
operator Volume Set Point. The Name channel will record the Mass Set Point.
Volume Controller, Mass SP: Used with a Volume Flow Controller for which the
operator Set Point is in Mass Flow. A second data channel will be created to record the
operator Mass Set Point. The Name channel will record the Volume Set Point.
Simple Controller: Used to define a controller channel that uses a simple semiproportional/deadband algorithm.
PID Controller: Like a simple controller, sets an analog output based on a process
variable (housekeeping channel) so as to control the process channel at a specified set
point. The analog output is determined via a proportional–integral–derivative (PID)
function. Note that up to 10 PID loop controllers can be configured.If more than 10 are
defined in the configuration, the 11th and higher will generate errors.
Follower: Used to define a Follower Analog Output channel, such that the voltage
output is proportional to a Housekeeping data channel value.
Manual: Used to define a new channel that is logged and the value of which is userspecified, but which does not correspond to an analog output channel.This channel
can be set by the operator manually to record an experimental parameter that
changes during an experiment. The user can set this channel to record an
experimental parameter that changes rarely during an experiment. It can also be set
by a CCL command so as to record a value from a remote system. Sequences can also
be used to manipulate these Manual channels, as is done when the Auto-Sampler
option is enabled.
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Some of these Controllers also create a new logical channel, which is named in New Channel
Name, described below.
All analog output channels are configured as single-ended.
Note that the software displays information for one Controller at a time. To see information
about additional Controllers, use the scrollbar at the bottom of the Controller window, or use
the Index control
in the upper left.
Users can add and delete Controllers using the InsertBefore, Insert After, and Delete
buttons. For each defined Controller, the user must enter some or all of the parameters
below.Parameters that are not relevant to a particular type of Controller are grayed out.
Controller Parameters
Definitions of the Controller Parameters are given below. Note that parameters may be
grayed out if they are not required for the selected Controller Type.
Type: This parameter is used to define the type of Controller channel that is being created—
Direct Setpoint, Simple Control, etc. (See previous page for definitions of these types.)
For a general-purpose analog output channel that is not a flow, a control loop, or a Follower,
select Direct Setpoint. This type implies that the analog output is the scaled set point, with
no additional influence from other channels.
Name: This is the name given to the Analog Output channel in engineering units.Note that if
the Controller channel is configured to convert a Volume Flow Set Point to a Mass Flow output
for a Mass Flow Controller, then this name is applied to the Mass Flow Set Point. A second
channel will also be recorded to the data stream with a name specified by New Channel
Name, and this second channel will contain the Set Point in Volume Flow that the user
actually enters. A similar second channel is created for a Volume Flow Controller that uses a
Mass Flow Set Point. Note that the actual voltage value that is output to the Analog Output
channel is not recorded directly for these Flow Controllers. When a Simple Controller or PID
Controller is used, a second Channel is created that records the actual voltage Set Point that
is sent to that Controller's Analog Output channel. This is necessary, since these control loops
need to know the previous voltage Set Point as well as the desired Set Point relative to the
Process Variable Channel.
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New Channel Name: This parameter defines the name of the new channel that some
controller Types create.
 For Mass Controller, Volume SP: A new channel is created for the set point in Volume
flow. The user interacts with the new channel—i.e., when the program is running, the
user changes this channel's value to change the controller. The channel specified by
Name, Dev, and Channel is the physical channel in Mass flow. The new channel stores the
new set point flow, not the actual voltage value that gets output to the to the analog
output channel.
 For Volume Controller, Mass SP: A new channel is created for the set point in Mass flow.
The user interacts with the new channel, and the channel specified by Name, Dev, and
Channel is the physical channel in Volume flow. The new channel stores the new set point
flow, not the actual voltage value that gets output to the to the analog output channel.
 For Simple Controller and PIDs: A new channel is created for the Voltage output sent to
the physical channel, which is associated with the specified Device and Channel. This is
necessary since these control loops need to know the previous voltage set point as well as
the desired set point relative to the Source channel. However, the channel specified by
Name is the set point that the user interacts with.
For Types that do not create a new channel, this parameter is grayed out.
Initial SetPoint: This defines the value of the Controller channel when the program first
starts, in the units that the operator uses to define the Set Point.Thus if the channel is
defined as a Mass Controller with a Volume Set Point, this parameter will have units of
Volume Flow.
Range: This specifies the output range in Volts that the analog output channel will be
configured to use for Direct Controllers, Flow Controllers, Simple Controllers, PID Controllers,
and Followers. This should be as large as necessary to span the required voltages, but as small
as possible to maximize resolution.Note that the 6036E board sometimes used for
Housekeeping only has 0 to 10V and -10 to 10V ranges.Nonetheless, even when a 6036E is
being used, this parameter will often be set to 0 to 5V range. The software limits the output
voltage to this range, which is useful since the flow meters and valves used often have a 0 to
5V range.
Dev and Channel: These parameters determine which National Instruments Device and
Channel are used for the Controller channel.Device names can be determined from within the
Measurement and Automation Explorer. Device names are typically a string such as Dev2, and
Device numbers start at 1. Channel numbers typically start at 0.
Min Change: For Flow Controllers, this parameter defines the minimum change to the Set
Point that is required before the analog output channel will be updated.If this is set to 0, the
output channel is always updated to the current Set Point value.However, for a channel such
as a Mass Flow Controller with Volume Flow Set Point, giving this parameter a small positive
value will ensure that small fluctuations or noise in pressure or temperature don't
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continuously move the Flow Set Point around.This parameter is used for Direct Controllers
and Flow Controllers.
Slope – Offset:These parameters are used for Flow Controllers and Followers. They define a
linear conversion from engineering units to Voltage.Thus this parameter has units of
Volts/Flow (or Volts/Engineering Units). For Flow Controllers, the Slope has the same flow
units as the hardware controller itself.(E.g. for a Mass Controller with Volume Set Point, the
Slope would have units of Volts/Mass Flow.)For PID controllers, this Slope is used to calculate
the voltage output for a Manual SetPoint when in Manual mode, and its inverse is used to
calculate an effective Manual Setpoint from the calculated PID output voltage when in
Control Loop mode.
Start up: This parameter is used for Simple Controllers and PID Controllers.These Types of
Controllers can be switched between Manual mode and Control Loop mode while the program
is running.In Manual mode, the user enters a Set Point in units of the output channel (Volts
for Simple Controllers, engineering units of the control channel for PID Controllers).The
analog output is then set directly from the specified Set Point.In Control Loop mode, the user
specifies the Set Point in the engineering units of the Process Variable and the control
algorithm is used to set the analog output. The Start-Up parameter determines which mode
the Controller starts in.
Pressure Ch: Mass Controller/Volume SP and Volume Controller/Mass SP types, this
parameter defines the Housekeeping channel that is used as the reference pressure for
converting Set Points between Mass and Volume Flows.
Temperature Ch: For Mass Controller/Volume SP and Volume Controller/Mass SP types, this
parameter defines the Housekeeping channel that is used as the reference temperature for
converting Set Points between Mass and Volume Flows. This drop-down list and the Pressure
Ch are populated with all the Housekeeping channels.
Process VarCh: This parameter is used to define the source (process variable) channel to be
used with Simple Controller, PID, and Follower channels.Note that this drop-down list is
populated with all the Housekeeping channels, not just the Analog Input channels.Thus a
Follower channel could be defined that uses any channel as its source, including calculated
concentrations, for example.
Deadband: This parameter defines the Deadband when comparing the Process Variable to the
Set Point. The difference between the Process Variable and Set Point mustexceed this
Deadband before the output to the channel is changed. This parameter is only used for Simple
Controllers.
Step Size (V): This parameter defines the Step Size in Volts that is taken if the Deadband
between the Process Variable Channel and Set Point is exceeded.(Note that if the difference
between the Process Variable Channel and Set Point is more than 5 times the Deadband, then
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this Step Size parameter is multiplied by 5 to give a semi-proportional control.)This
parameter is only used for Simple Controllers.
Initial Set Point (V): This parameter defines the initial output Set Point, e.g. the starting
voltage put out on the D/A channel initially. This parameter is only used for Simple
Controllers.
Kc: This parameter specifies the Proportional Gain Kc for PID Controllers.
Ti (min):This parameter specifies the Integral Time in minutes for PID Controllers.
Td (min):This parameter specifies the Derivative Time in minutes for PID Controllers.
Min SP: For PID controllers, this parameter specifies the minimum Set Point in Engineering
Units that the program is allowed to set the output to. Inside the program, this value is
converted to Volts by using the Slope and Offset. This value is ignored if Max SP is set to 0.
Max SP: For PID controllers, this parameter specifies the maximum Set Point in Engineering
Units that the program is allowed to set the output to.Inside the program, this value is
converted to Volts by using the Slope and Offset.This parameter and the Min SP are ignored if
Max SP is set to 0.Note that the output is also limited by the Range parameter.
Note that all analog output channels used for Controllers are configured as single-ended.
Note on Set Point Conversions
When calculating a set point conversion, a standard temperature of 273.16 ºK is used, as is a
standard pressure of 1013.25 mBar. The Temperature channel is assumed to be in ºC, and the
Pressure channel is assumed to be in mBar.
Note on Timing
The controller channels are calculated and updated by the main control program, not by the
housekeeping program, and are thus updated at the cycle rate of the main program. They use
the most recent values of housekeeping data in the calculations, and their resulting values
are transmitted back to the housekeeping program for recording.Hence the housekeeping
channel values recorded at time t(n) will be used at time t(n + delta) to calculate Controller
channel set points, and these set points will be recorded in the housekeeping data file at time
t(n + 1).
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8.6.5.2
Flow Meters
The Flow Meters parameters allow you to create additional housekeeping channels that
rescale a measured, physical volume or mass flow meter into a virtual mass or volume flow
meter. They can also be used to create a new virtual channel that is simply a multiplicative
scaling of an existing channel. To insert a flow meter, press the green Insert button and enter
the parameters below. To delete a meter, press the red Delete button. After editing Flow
Meters, you must click on Save Changes and Restart Program for changes to take effect.
Flow Meter Parameters
Virtual Meter: This is the name assigned to the newly created channel.
Physical Meter: This drop-down list selects which existing housekeeping channel is used as
the source of the flow measurement.
Pressure and Temperature: These are the reference pressure and temperature, respectively,
used for converting between mass flow and volume flow or vice versa. You can select these
parameters from a drop-down list of housekeeping channels.
Scale Factor: This parameter is used with the “Re-scale” Type to determine how the physical
meter channel is scaled to calculate the virtual meter channel.
Type: This parameter determines the type of conversion that creates the virtual meter.
There are three options:
1.) Converting a physical mass flow meter to volume flow
2.) Converting a physical volume flow meter to mass flow
3.) Multiplying the physical meter channel by a scale factor
Conversions
When calculating conversions, a standard temperature of 273.16 ºK is used, as is a standard
pressure of 1013.25 mBar. The Temperature channel is assumed to be in ºC, and the
Pressure channel is assumed to be in mBar.
Note on Timing
Each flow meter channel that is defined on this tab is calculated for each housekeeping cycle.
The calculated values correspond directly to the physical meter value for the same cycle of
housekeeping data.
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8.6.5.3
Alicat Flow Controller
The Alicat Flow Controller is an optional feature. The SPIN program supports one Alicat Flow
Controller. In order for this Flow Controller to be functional, the user must define the
parameters below.
The Name parameter is prepended to the set-point channel and to the housekeeping channels
(pressure, temperature, and flow) read back from the Alicat. For instance, if you enter
“Alicat FC” in the Name field, the Alicat-related channels will be named as follows:
 Alicat FC Set Point (vccm)
 Alicat FC Read (vol)
 Alicat FC Read (mass)
 Alicat FC Temp. (C)
 Alicat FC Pres. (mBar)
Full Scale is used to define the full scale flow for the Alicat Flow controller being used.
Units should be set to the native units of the Alicat Flow Controller (e.g., sccm). The program
does not do any rescaling between units, but only uses the Units parameter as a suffix to the
Alicat channel names.
Enable/Disable is used to select whether or not the program includes the Alicat Flow
Controller. If the switch is set to Disable, no Alicat channels will appear among the
housekeeping channels.
Com Port defines which serial port is used to control the Alicat Flow Controller.
Flow defines the initial set point that the Alicat is set to. Units of this parameter are the
native units of the Alicat model being used.
8.6.6
Alarms and Timers Sub-tab
The Alarm parameters control not only when alarms get generated but which actions are
taken as a consequence of alarms. Users can add and delete alarms using the Insert and
Delete buttons to the right of the alarms.
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Figure 39: Alarms and Timers Sub-tab
8.6.6.1
Alarms
Parameters
Nameis used for the alarm name. This name is useful for clarity, so that the operator knows the
purpose of the alarm.It is also used programmatically to refer to the alarm so that its threshold
can be changed by a Sequence, CCL command, or another alarm.
Channel determines which of the housekeeping data channels is used for the alarm comparison.
Condition selects which logical condition is applied to the selected channel: <, <=, =, <> (not
equal), >=, or >.
Threshold defines the value that the channel will be compared to when determining if an alarm is
true or not.
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Hysteresis allows the alarm to be configured such that small amounts of noise near the Threshold
value will not continually set and clear the alarm. For the < and <= commands, once the alarm has
been triggered, the value of the channel must go above [Threshold + Hysteresis] before the alarm
can turn off.For the > and >= commands, the value of the channel must fall below [Threshold Hysteresis] before the alarm can turn off. For = and <> commands, Hysteresis is ignored.
Action defines what action will be taken when the alarm transitions from false to true. In addition
to this action, the transition will also be noted in the log file. (When an alarm transitions from true
to false, the transition is logged but no other action is taken.) For a complete list of actions, see
Appendix E.
Note that most of the Actions are not inherently bi-directional.That is, when an alarm goes from
true to false, the opposite action is not executed.E.g. a “Turn Laser Off Alarm” will not turn the
laser back on when the alarm becomes false.
Note also that not all Actions will use all of the listed parameters.
Min Time specifies the minimum amount of time in seconds that the alarm condition must be met
before the alarm is set to true.Set this to 0 to have an alarm work as soon as the condition is
detected.If Min Time is set to a larger value, short excursions past the alarm condition will not
cause the Action to be executed.Note that when an alarm condition is met but the minimum time
has not yet elapsed, the Alarm goes to it Warning state, indicated by a Yellow alarm color.
Set Value and Target Channel are used by the “Set Channel” and “Add to Channel” actions to
allow an output channel to be set to a new value if an alarm becomes true. Target Channel is also
used by the “Set Ch to Manual” and “Set Ch to Control” actions.
Sequence is used by the “Start Sequence” and “Stop Sequence” actions. This parameter specifies
which sequence should be started or stopped when the alarm becomes true.
Target Alarmis used by the “Set Alarm Thresh Action” action to change the threshold of an Alarm
to the value specified by the “Set Value” parameter.
The Set Value parameter is used to specify the numeric value that the Action uses.
Examples of How to Set Parameters for Alarms
Example 1:
Name: Auto Data Record
Channel:Elapsed Time
Condition:>
Threshold:60
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Hysteresis:0
Action:Start Writing Data
Min Time:0
Set Value:0
Sequence:n.a.
Target Channel:n.a.
This alarm will cause the program to begin writing data to a file after the program has run for 60
seconds.
Example 2: (default Alarm)
Name: Alarm Alert
Channel:Error
Condition:<>
Threshold:0
Hysteresis:0
Action:Alert
Min Time:0
Set Value:0
Sequence: n.a.
Target Channel:n.a.
This default alarm causes an alarm to be true whenever an error is logged. This ensures that the
Alarm Status indicator at the top of the main program display turns red each time an error occurs.
This alerts the user to the error condition even when the program is not displaying the Status tab.
8.6.6.2
Timers
Timers are virtual channels within the SPIN system used to count time. Any number of Timer
channels can be defined. The only parameter for a Timer channel is its name.Each Timer
starts with a value of 0 when the SPIN program starts and counts up in units of seconds. A
Timer can be set to any value using the Set Channel button on the Control tab, or using a
Sequence, Alarm, or CCL action. When set to a new value, it will start counting up from there
immediately. Most often, Timers will be created so that Sequences can act according to time
elapsed from specific events.
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8.6.7
Calculations Sub-Tab
Figure 14 shows the important components of the Calculations sub-tab.
Allows user to import pre-defined calculations and view details about them.
Allows user to add channels
to the output file. These
channels are calculated
based on existing channels.
Lists all channels in the
system, so user can copy
and paste them into
Calculated Channels.For
reference only.
Permits user to set global
variables, which can then be
used in Calculation VIs (i.e.,
“Available Calculations”).
Figure 40: Calculations Sub-tab--Important Components
AvailableCalculations and Defined Calculations provide a mechanism for including additional
calculated channels. This feature is useful for users who want to employ algorithms and
equations that are not included in the SPIN software. Each item listed in Available
Calculations is a LabVIEW VI stored in C:\DMT\SPIN Support\Calculations. Each of
these VIs must adhere exactly to the pattern defined by DMT for it to function properly in the
SPIN software, and VIs must be written in LabVIEW 2010. For more information on how to
create a new Calculation, open the Demo Calculation.vi in LabVIEW 2010.
Double-clicking on an Available Calculation adds it to the list of Defined Calculations, which
will be used when the SPIN system runs. Click on a Defined Calculation to highlight it and
display its parameters in the box below. The parameters contain the name of the calculation,
a description (which is stored on the actual calculation VI), and a list of Input and Output
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Channels. The Input Channels are selected from a list of all the SPIN channels. The Output
Channels are given names and will be added to the list of channels in the SPIN output file.
Note that each Available Calculation can only be added once to the Defined Calculation. To
duplicate a calculation so that it can be re-used with different input channels, copy the
calculation VI in C:\DMT\SPIN Support\Calculations and make a new copy with a
different name.
Calculated Channels are virtual channels, the values of which are calculated from the
current values of other channels. To enter or remove Calculated Channels, use the Insert and
Delete buttons.
Each Calculated Channel has a Name and a Formula. The Name is how the channel is referred
to in the SPIN system. The Formula is simple algebraic text that can incorporate any number
of other channel names. An exampleFormulais shown below. Appendix G contains a complete
list of functions available for use in calculated channels.
Note that the Calculated Channels are calculated in the order in which they appear in the
Calculated Channels array. For one Calculated Channel to refer to another, the referenced
Calculated Channel must appear earlier (higher) in the list than the channel making reference
to it.
To calculate an average temperature based on several measured temperatures, the following
formula could be used:
(Top Temp (C) + Middle Temp (C) + Bottom Temp (C))/3
Note that the text entered in the Formula parameter does not include the Calculated Channel
Name or an equals sign.
Five nominally unassigned Global Variables are available. The first of these is named Num to
Avg and is used by the Channel Averager.vi calculation VI. The Num to Avgglobal
specifies the number of points that are averaged together to create a new averaged-value
channel. The remaining globals (Global 2 to Global 5) can be used by other Calculation VIs for
any purpose desired. They provide a way to pass simple configuration information from the
main configuration to the Calculation VIs.
The array named All Channels is for reference when creating Calculated Channels. It lists all
the channels currently defined in the SPIN system. These names can be highlighted with the
mouse, then copied (CTRL-C) and pasted (CTRL-V) into the Calculated Channels Formulas.
For examples showing to how to create a calculation and how to import a predefined
calculation, see sections 3.4.1 and 3.4.2, respectively.
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8.6.8
Communication Sub-Tab
The Communications sub-tab provides ways to configure three different communications
mechanisms that the SPIN software can optionally use:



OSDS Format: allows the user to specify protocols for streaming in data from an
arbitrary external device. For example, this feature can be used to have an aircraftnavigation system feed in data to the SPIN computer over an Ethernet connection or
serial port. It can also be used to stream in data from other DMT instruments and
instruments commonly used in the atmospheric sciences.
Streaming Channels: allows one to send SPIN Housekeeping data over a serial or UDP
port to other systems.
Common Command Language (CCL) Support: provides a way for the SPIN software to
receive commands from other systems over a serial port.
Figure 41: Communication Sub-tab
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8.6.8.1
OSDS Format
The SPIN streams in and parses data according to specifications given in OCC Streaming Data
System (OSDS) format files. OSDS is a module for reading streaming data from a wide variety
of sources. You may specify a predefined OSDS Format File or edit the format and save it to a
new OSDS Format File. Leave the OSDS Format File blank to ignore the OSDS input
completely. See www.originalcode.com/OSDS.html for details on OSDS. The parameters listed
in the gray OSDS Format table are also described in C:\DMT\SPIN Support\OSDS\OSDS
Description.doc.
Note that changes made to the OSDS Format will not be effective until the OSDS Format has
been saved to a file, the OSDS Format file selection has been saved to the SPIN configuration
file, and the user hits Restart Program.
Load OSDS Format allows you to select a preconfigured OSDS format file to be used by the
SPIN software. By default, the SPIN system stores these files in the C:\DMT\SPIN
Support\OSDS\OSDS Format Files directory. When the Load button is clicked, the
software will open this directory and allow you to select an OSDS format file.
Another way to load an OSDS file is to click on the Folder icon next to the “OSDS Format File”
label.
OSDS Format File lists the currently loaded file.
Save OSDS Format saves any changes made to the OSDS parameters to a file. You must save
to the OSDS file before changes will be effective. Saving just the SPIN configuration file is not
sufficient.
8.6.8.2
Streaming Channels
Streaming Channels is an array that contains the SPIN data channels to be streamed out. The
box to the top left of the array shows the element in the array that is currently displayed in
the top row. Arrays begin with element zero. The arrows to the left of this box, or the scroll
bar to the right of the channel list, are used to move forward or backward in the array.
To add a channel to the end of the data stream, click on the first empty box after the
currently listed channels. This will bring up a list of available SPIN channels, from which the
desired channel can be selected (Figure 42).
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Figure 42: Selecting a Channel for Inclusion in Streamed Output Data
Use the green and red buttons to insert and delete rows in the array.
Port determines the serial port or UDP port number used for Streaming Output Data, if there
are any. If this is set to 0, no data are streamed. Streaming data are sent at the same rate as
the cycle time for housekeeping.
Baud Rate determines the Baud Rate used by the streaming output data over a serial port.
The other serial port settings are fixed at 8 Data Bits, 1 Stop Bit, and No Parity. This
parameter is ignored if Bus is set to UDP.
Bus is used to determine if the Streaming Data is sent out a Serial port or by UDP over
Ethernet.
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8.6.8.3
Common Command Language Support
CCL Com Port determines the serial port number used for communicating with the SPIN via
the Common Command Language. If this is set to 0, no port is opened for CCL commands and
communication is disabled. Further information about CCL communication appears in
Appendix F.
8.6.9
Sequences Sub-Tab
The Sequences sub-tab is displayed below.
Figure 43: Sequences Sub-tab
Sequences are configurable sequences of events that can control the SPIN system in a wide
variety of ways. The left-most list on the window, Sequences, displays the names of the
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Sequences that have been defined. Use the buttons below it to add new Sequences or delete
existing ones. New sequences will be placed relative to the highlighted sequence.
The second list, Steps, shows the Steps that are defined for whichever Sequence is
highlighted in the first list. These Steps are identified by their Labels. Use the buttons below
the Steps field to add new Steps or delete existing Steps. New steps will be placed relative to
the highlighted steps.
The Sequence Name parameter displays the name of the Sequence that is currently
highlighted in the list to the far left. The Sequence Name can be edited in this control.Do not
use special characters like dashes in Sequence Names, as these will generate a LabVIEW error.
Log Each Stop/Don't Log determines whether a Log File entry will be created as each step of
the Sequence is executed. Enabling this option can make the Log File fairly verbose, but can
be useful for debugging or for keeping a record of when certain actions were taken.
The Create Switch/No Switch parameter determines whether the Sequence being edited will
have an operator switch present on the Control tab of the SPIN window (Figure 44). Creating a
switch is an easy way to give manual control over a Sequence. However, Sequences can also
be started and stopped by Alarms, CCL Commands, or other Sequences.
Figure 44: Example Sequence Switch on Control Tab
The Sequence Step parameters display the definition of whichever Step is currently
highlighted in the Steps list. For definitions of Step parameters, see section 8.6.9.1 below.
Include Exit Step/No Exit Step allows the user to specify an Exit Step to be run each time the
sequence stops. Exit Step parameters are defined in section 8.6.9.1 below. For more
information on Exit Steps and their possible uses, see section 3.2.1.
Export Sequence allows one to save the currently highlighted Sequence in a small .seq file.
Import Sequence will read a Sequence in from a .seq file. Import and Export can be useful
for sharing Sequences between instruments or configuration files.
8.6.9.1
Step Parameters
The Sequence Step parameters display the definition of whichever Step is currently
highlighted in the Steps list.
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The Label is an optional identifier. Although the Label is not required for each Step, giving
every Step a meaningful, unique Label greatly increases the readability of the Sequences. In
addition, some sequence actions like Goto and Log require a Label as an input parameter.
Hence any Step that one of these Actions refers to must have a unique Label. If more than
one Step has the same name, the Sequence Engine will use the first appropriately named Step
that it can find. Note that Sequences can only refer to Steps within themselves, not to Steps
within other Sequences. Thus having unique Labels for all Steps across all Sequences is not
strictly necessary, but can improve clarity.
The Action defines what the Sequence Step will do, assuming that the Condition is met. Most
Actions only require a subset of the available parameters. Only those parameters that are
relevant to that Action will be shown. Below are a few example Actions:





Wait (Value): waits n seconds before executing the next Sequence Step, where n is
defined by the Value parameter. Note that n may contain a fractional second, though
the Sequence Engine is not accurate in its timing to better than about 0.2 seconds.
Restart Files: starts new Data, Housekeeping, and Log files and makes a new archive
copy of the Configuration file. If midnight has passed, it starts a new date directory.
Goto: jumps to the Step of the same Sequence defined by the Target Label parameter.
Goto cannot be used to jump into another Sequence.
Log: writes the Sequence Label to the Log File with a time stamp. In this case, the
Label may be rather lengthy in order to convey adequate information.
Set Channel: sets the value of the channel specified by Target Channel to the Value
parameter. Only control channels and Timers can be selected as a Target Channel.
For a complete list of available actions and their definitions, see Appendix E.
Note that different actions require different parameters. Hence, the parameters listed in the
Sequence Step control box will change depending on the type of action you select.
Condition determines the condition that must be True for the Step to execute. If this
Condition is set to True, the Step will always execute. False prevents the Step from ever
executing. Other Conditions are used with the current value of the Condition Channel in
comparison to the Threshold parameter. Thus if the Condition is <, and the Threshold is 5.0,
the Step will only be executed if the current value of the Target Channel is less than 5.0. If
the Condition is not met, the Sequence will step directly to the next Step with a minimal
delay of about 20 ms.
Source is used by certain Actions that require a channel to supply a value. These Actions
include Wait (Channel), Copy Channel, Add Channels, Subtract Channels, Multiply Channels,
and Divide Channels. For these last four mathematical operations, the Target is used as the
first operand, the Source is used as the second operand, and the result is put into the Target
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Channel. Thus Divide Channels will take the Target Channel value and divide it by the Source
Channel value, and save the result in the Target Channel.
Target Channel is used by Set Channel, Increment Channel, Add To Channel, Set Ch to
Manual, and Set Ch to Control Actions to determine which channel to act on.
Sequence is used by the Start Sequence and Stop Sequence Actions to determine which
Sequence to act on. Note that any number of Sequences can be running at any time.
Target Label is used by the Goto Action to determine where the Sequence should jump to.
Value is used by the Wait (Value), Set Channel, and Add To Channel Actions. Note that Value
can have precision of less than one, allowing waits of less than 1 second, for example.
However, the accuracy with which the program will time Waits of less than 1 second is
marginal.
The Reset to Defaults button in the bottom left of the screen resets all sequences to their
initial DMT configuration.
8.6.10 Custom Sub-tab
8.6.10.1 Overview
The Custom sub-tab allows users to add, name, and configure a new tab in the SPIN software.
A custom-designed tab can display time-series graphs, a Control channel, sequence switches,
and ON/OFF switches for digital output channels. Users can control the Control channel,
sequences, and digital outputs from this tab.
The Custom Display tab can be configured to show an arbitrary number of custom displays.
Each such display is a Set, with aname and a set of parameters that define how the Custom
Display will appear.
8.6.10.2 Parameters
Tab Name is the name of the Custom tab as it will be displayed in the SPIN program. See
Figure 45. This name should be kept as short as possible. If this field is left blank, the Custom
tab will be hidden.
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Figure 45: Using the Config > Custom Tab to Name and Define a Custom Tab
Display Sets is a list of all the Display Sets that have been defined. (See section 8.6.10.1for
more information on Sets.) Click on one Display Set in this box to edit its properties. The
buttons beneath the Display Sets list allow you to add and remove Display Sets.Insert Before
and Insert After can be used to add new Display Sets relative to whichever one is currently
highlighted. Delete will remove the highlighted Display Set.
Display Set Name is used to label the Display Set that is currently being edited. These names
will populate a drop-down menu item on the Custom Display to allow the user to select which
Display Set is being shown.
Graph 1 Plots allows the selection of up to eleven channels to display on the top time-series
graph of the Custom display. The Y axis (left or right) for each plot can be individually
selected.The X axis is always Time.
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Graph 2 Plots allows the selection of up to seven channels to display on the middle timeseries graph of the Custom display. The Y axis (left or right) for each plot can be individually
selected. The X axis is always time.
Graph 3 Plots allows the selection of up to four channels to display on the bottom time-series
graph of the Custom display. The Y axis (left or right) for each plot can be individually
selected. The X axis is always time. Note that if more than two channels are displayed on
Graph 3, Digital Output 1 will not be available. If more than four channels are displayed on
Graph 3, Digital Output 2 will not be available.
Control Channel specifies an Analog Output Control channel that can be controlled directly
from the Custom display. Only Controller channels are included in this list, not Digital
Outputs, Alicat Set Points, or other control channels. If this item is left blank, the Control
Channel will not appear on the Custom display.
Sequence 1 and Sequence 2 can be used to specify two Sequences that can be started and
stopped directly from the Custom display. If these are left blank, then the Sequence controls
will not appear on the Custom display.
Digital Output 1 and Digital Output 2 can be used to specify two Digital Output channels that
can be turned on and off directly from the Custom display. If these are left blank, then the
Digital Output controls will not appear on the Custom display. Note that if Graph 3 has more
than two channels displayed, Digital Output 1 will not appear on the Custom display. If Graph
3 has more than 3 channels, Digital Output 2 will not appear on the Custom display.
8.7
Utility Tab
The Utility tab provides space to display additional utilities associated with the SPIN
software. These utilities are accessed via the Utilitiesmenu. Figure 46 shows the Utilities tab
display after the SPIN Data Reader Program has been loaded.
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Figure 46: SPIN Data Reader
The Utility tab is often used to view previously acquired data in playback mode, via the Data
Readerand Log Reader. The Sequence Editor utility assists users in creating, loading and
saving sequences. Additional information about SPIN utilities is provided below.Other utilities
may be added to the SPIN program in the future.
All utilities have a STOP button that terminates the utility.
8.7.1
SPIN Data Reader Program
The data reader program (Figure 46) displays previously acquired SPIN data. This program can
be loaded by clicking on the Utilities menu item and selecting “Data Reader.”
Once the Data Reader is active, users load an *.csv file by clicking on the Read a File button
and then navigating to the desired location. The window to the right of this button displays
the currently loaded file.
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The Data Reader displays two graphs of user-selectable channels. To change these channels,
click on the white controls beneath the histogram. The software will display a list of available
channels from which you can select the desired value. Note that the two graphs share an Xaxis channel, which is typically set to Time (sec).
The time controls in the upper right (Figure 47) can be used to advance or go back in time.
Figure 47: Data Reader Time Controls
8.7.2
SPIN Log Reader
The Log Reader (Figure 48) displays the contents of SPIN log file. This program can be loaded
by clicking on the Utilities menu item and selecting “Log Reader.”
When this utility is loaded, it automatically loads the current log file. In this mode, the log
file display will continuously be updated as new entries are made in the log file. If the Read a
File button is pressed, an older log file can be read in, in which case the log file display is
static.
The currently displayed log file is listed to the right of the Read a File button.
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Figure 48: Utility Tab—SPIN Log Reader
8.7.3
Sequence Editor
The Sequence Editor is shown inFigure 49. The buttons on left allow the user to read and save
sequence files.
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Figure 49: UtilityTab—SPIN Sequence Editor
Click on a sequence under Sequences in SPIN to view or edit it. A list of steps in the
sequence will appear in Steps in the upper right. Details about each of these steps (action
taken, condition channel, threshold, value, etc.) appear in the table below. You can modify
these steps directly in the table. For explanations of available actions, see Appendix E.
The Log/Don’t Log switch specifies whether each individual step in the sequence should be
recorded in the log file. While recording each step can be useful for debugging purposes, it
also generates a very long log file.
Create Switch/No Switch determines whether the sequence will have a button on the Control
tab. These buttons are useful in starting and stopping sequences, so this control should be set
to Create Switch for frequently used sequences. Sequences that are only called
programmatically (by other sequences or by alarms) can have this set to “No Switch” since
they do not need a switch.
To create a new sequence, fill in the Sequence Name. Do not use special characters like
dashes, as these will generate a LabVIEW error. Next, use the Insert buttons to add steps.
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Once you click on Insert, you will be able to name the step and specify an action in the table
below. You can also simply edit the existing steps by changing their parameters (Label,
Action, Condition Channel, and so on).
Note: The Sequence Editor does not currently allow the user to create exit steps for
sequences. This functionality will be added to a future version of the software. In the
meantime, if you wish to create exit steps, do so from the Config > Sequences tab.
Note: Sequences added with the Sequence Editor will show up on sequence tab. By default
they will NOT show up on the Config > Sequences tab, but they will when you click the Load
Startup Config button.
9.0
Troubleshooting
Several of the SPIN output channels provide useful instrument-health information. The following
channels are particularly important indicators:
How can I tell if the system is leaking refrigerant?
The three CmprOutPres (psi) channels—Cold 1st Cmpr Out Pres (psi), Cold 2nd Cmpr Out Pres
(psi), and Warm Cmpr Out Pres (psi)—indicate the static refrigerant charge. If you see any of these
indicators dropping steadily over the course of several weeks, it indicates refrigerant is being lost.
This can be due to a leak in the system.
How can I tell if the sample inlet is icing over, and what should I do if this occurs?
At times the sample inlet may accumulate ice on its edge, blocking the incoming sample air.
If the SPIN is operating normally and the Chamber Inlet Differential Pressure moves outside
its expected range of .1 to .4, check the inlet to see if it is iced over. If it is, use a heat gun
to apply heat to the inlet and melt the ice.
Appendix A: Specifications
Technique:
Measured Parameters:
Measured Particle
Size Range:
Parallel-plate geometry chamber for nucleation;
optical particle counter to detect forward-scattered
and depolarized light from resulting particles


Particle size
Particle phase (ice vs. water)
0.8 – 20 µm
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Particle Residence Time in
Chamber:
Refrigeration System:
Computer System:
10 – 12 seconds
Compact system that cools plates directly:
 Cold plate temperature to -70° C
 Warm plate temperature to -40° C


Power Requirements:
Dimensions:
LabVIEW-based software provides full control of
all instrument systems
Automated operation for unattended
measurements
220 VAC, 50/60 Hz, 3000 W or 28 VDC, 3000 W
Self-contained in a single rack, 59 cm wide x 73 cm
deep x 167 cm high
Appendix B: SPIN Software Architecture
The SPIN software program consists of several different loops or sub-programs, as follows:



Control Program—This loop starts and stops the other modules, updates the displays,
controls the instrument set points, watches the alarms, and otherwise supervises the
operation of the entire system.
Data Acquisition Loop—This loop acquires data for particle events. Data is acquired in
buffers of typically 500,000 to 1,000,000 points in each channel, with 200 to 400 ns
between each data point. This loop acquires data continuously and passes the data
buffers to the Data Processing Loop.
Data Processing Loop—This loop examines the data buffers acquired by the Data
Acquisition Loop and identifies events within those buffers. It extracts the events,
saves them to disk, and supplies them to the Control Program for display. If data loads
are high and the CPU cannot keep up with this processing, some buffers from the Data
Acquisition Loop will be ignored and the duty cycle of the acquisition will drop to less
than 100%.
In addition, there are a Data Reader, a Log Reader, and a Sequence Editor. These are
integrated into the main program in the Utilities menu item, and the Data Reader can also be
run as a separate program.
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Appendix C: Output Files
The SPIN program generates several output files:
1.) *.csvfiles, which contains output channel data:
a. Main data file
b. PbP data file(s)
2.) A *.log file, which contains the error and event logs
3.) An *.ini file, which contains configuration settings
Files are stored in a date-stamped folder (YYMMDD) in the directory specified on the
Acquisition tab (a sub-tab under the Config tab). By default, this data path is C:\DMT\SPIN
Data.
See below for information about the names and contents of these files.
*.csv Files
Main Data File
The main data file names contain the same date stamp as a folder, plus a suffix with a timestamp. E.g., SPIN007 20110427114802.csv indicates that the data file started being
recorded at 11:48:02 a.m. on April 27, 2011. The three digits after the SPIN indicate the
instrument serial number (seven, in the example above).
Below is a list of default output channels in the main SPIN data file. Note that your output
channels may differ if you have created new channels in your configuration. These channels
are defined at the bottom of this list.
Time (sec)
Timestamp
Elapsed Time
Error Code
Sum of Transit
Size Overflow
P2 Overflow
S1 Overflow
P1 Overflow
Size PbP Rejects
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Sheath Flow SP (slpm)
Sample Flow SP (slpm)
Warm Loop PID Out
Warm Loop PID Off Time
Cold2 LIQ Sol Top Loop PID Out
Cold2 LIQ Sol Top Loop PID Off Time
Cold2 LIQ Sol Bottom Loop PID Out
Cold2 LIQ Sol Bottom Loop PID Off Time
Cold2 Mid Top Loop PID Out
Cold2 Mid Top Loop PID Off Time
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P2 Rejects
S1 Rejects
P1 Rejects
Total Particles
Dropped PbP Particles
Unused 0 – 5
Analog 0 – 5
Block Temp (C)
Laser Pwr Monitor (V)
Analog 8 – 14
P2 High Gain Baseline (V)
P2 Low Gain Baseline (V)
S1 High Gain Baseline (V)
Size High Gain Baseline (V)
Size Low Gain Baseline (V)
S1 Low Gain Baseline (V)
P1 High Gain Baseline (V)
P1 Low Gain Baseline (V)
Analog 23
Internal Temp (C)
Analog 25 – 30
Bin 1 – 20
Warm Cmpr In Pres (psi)
Warm Cmpr Out Pres (psi)
Cold 1st Cmpr In Pres (psi)
Cold 1st Cmpr Out Pres (psi)
Cold 2nd Cmpr In Pres (psi)
Cold 2nd Cmpr Out Pres (psi)
Sample Flow Signal (V)
Sheath Flow Signal (V)
Power Supply Curr (A)
Chamber Inlet differential Pres
Inlet Pressure Drop
Laser Current (A)
Warm Cmpr In Temp (C)
Warm Cmpr Out Temp (C)
Warm Mid Top Temp (C)
Cold 1st In Temp (C)
Cold 1st Out Temp (C)
Cold Mid Bot Temp (C)
Cold 2nd In Temp (C)
Cold 2nd Out Temp (C)
Warm Top Temp (C)
Warm Mid Bot Temp (C)
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Cold2 Mid Bot Loop PID Out
Cold2 Mid Bot Loop PID Off Time
Laser Mod SP (V)
Warm LIQ Sol
Warm Bypass Sol
Cold2 LIQ Sol Top
Cold2 LIQ Sol Mid Top
Cold2 LIQ Sol Mid Bot
Cold2 LIQ Sol Bottom
Warm CMP Enable
Cold1 CMP Enable
Cold2 CMP Enable
H2O Pump Fill /Empty
H2O Pump ON
Air Inlet
Purge
Sheath Pump ON
Sample Pump ON
Inlet Valve Inlet/Zero
Outlet Valve Sample/Fill
LED COLD PLATE blue
LED WARM PLATE blue
Warm Heater
Cold Heater
Liquid Level 1
Liquid Level 2
Liquid Level 3
Warm Cmpr Fault
Cold 2nd Cmpr Fault
Cold 1st Cmpr Fault
Fill Timer
Drain Timer
Cold2 Timer
# Conc (#/cm^3)
VolConc (g/m^3)
MVD (um)
ED (um)
P2 / Size
S1 / Size
P1 / Size
S1 / P2
S1 / P1
Detector Enabled?
Avg Warm Temp (C)
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Warm Bottom Temp (C)
Cold Top Temp (C)
Cold Mid Top Temp (C)
Cold Bottom Temp (C)
Evap Warm (C)
Evap Cold (C)
Warm Cmpr (RPM)
Cold 1st Cmpr (RPM)
Cold 2nd Cmpr (RPM)
Ice Dwell Counter
In Sequence?
Number of Purges
Warm Cmpr SP (RPM)
Cold 1st Cmpr SP (RPM)
Cold 2nd Cmpr SP (RPM)
Avg Top Temp Cold (C)
Avg Bot Temp Cold (C)
Aerosol Temp (C)
Avg Cold Wall Temp
Warm PID On Time
Cold2 LIQ Sol Top PID On Time
Cold2 LIQ Sol Bottom PID On Time
Cold2 Mid Top PID On Time
Cold2 Mid Bot PID On Time
Cold Plate LED On?
Warm Plate LED On?
P liq Cold Wall (mBar)
P liq Warm Wall (mBar)
P Water Sample (mBar)
SS% Water
SS% Ice
Channel Definitions
Definitions for channels appear below. Note the following conventions are used for channel
names:
 “Cold” and “Warm” refer to the cold and warm plates.
 “Cold 1” and “Cold 2” refer to the cold plate’s first and second compressors. (The
warm plate only has one compressor.)
 Terms such as “Top” and “Bottom” can refer either to the thermocouples (which
simply read temperatures) or to the cold plate’s temperature zones (areas on the
plate where the temperatureis controlled by a common PID loop). Check each
channel’s definition for more information. Thermocouple-related channels appear in
sets of four (Top, Mid Top, Mid Bottom, Bottom) while the cold zone’s temperaturezone-related channels appear in sets of two (Top and Bottom).
# Conc (#/cm^3): The particle number concentration—that is, the number of particles per
cubic centimeter.
Aerosol Target (C): The average temperature between the warm and cold plates. For
instance, if the warm plate temperature is -20 ˚C and the cold plate temperature is -30 ˚C,
the Aerosol Target (C) is -25.
Aerosol Temp (C):The temperature of the aerosol entering the SPIN inlet.
Air Inlet:A digital output parameter that the SPIN uses in the Purge Sample Tube sequence.
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Analog x: Unused analog channels from the detector (as opposed to analog channels defined
on the Config > Analog In tab).
Avg Bot Temp Cold (C):The average of the temperaturesreported by the bottom two
thermocouples in the cold refrigeration plate.
Avg Cold Wall Temp (C):The average of the temperatures reported by all four thermocouples
on the cold refrigeration plate.
Avg Top Temp Cold (C):The average of the temperatures reported by the top two
thermocouples in the cold refrigeration plate.
Avg Warm Temp (C):The average of the temperatures reported by the two thermocouples in
the warm refrigeration plate.
Bin 1-20: The counts in each of the SPIN’s sizing bins. Bin 1 will have the smallest particles,
Bin 20 the largest. The software uses threshold tables to determine particle sizes from the
electronics signals. These threshold tables are stored in the Config file and can be modified
from the Config > Acquisition tab.
Block Temp (C): The temperature of the optics block. The temperature should stay near
ambient temperature, so approximately 22 – 28 ºC. If the backward block overcools or
overheats, it can cause problems.
Chamber Inlet differential Pres: The differential pressure on the sample inlet. This channel
is used to determine if the Sample Inlet is iced over, in which case the refrigeration needs to
be shut down.
Cold 1st Cmpr (RPM): The rotations per minute of the first cold-plate compressor.
Cold 1st Cmpr Fault: A Boolean value that is 1 if the first cold-plate compressor has faulted.
See the following section, “Fault Conditions,” for more information.
Cold 1st CmprInPres (psi): The pressure on the inlet of the first cold-plate compressor. This
reading should be approximately 0-20 psi when the compressor is functioning.
Cold 1st CmprOutPres (psi): The pressure on the outlet of the first cold-plate compressor.
This reading should be approximately 80-300psi when the compressor is functioning.
Cold 1st Cmpr SP (RPM): The set-point number of rotations per minute for the first cold-plate
compressor.
Cold 1st In Temp (C): The temperature at the inlet of the first cold-plate compressor.
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Cold 1st Out Temp (C):The temperature at the outlet of the first cold-plate compressor.
Cold 2nd Cmpr (RPM): The set-point number of rotations per minute for the first cold-plate
compressor.
Cold 2nd Cmpr Fault:A Boolean value that is 1 if the second cold-plate compressor has
faulted. See the following section, “Fault Conditions,” for more information.
Cold 2nd CmprInPres (psi): The pressure on the inlet of the second cold-plate compressor.
This reading should be approximately 0-20 psi when the compressor is functioning.
Cold 2nd CmprOutPres (psi):The pressure on the outlet of the second cold-plate compressor.
This reading should be approximately 80-300 psi when the compressor is functioning.
Cold 2nd Cmpr SP (RPM): The set-point number of rotations per minute for the first coldplate compressor.
Cold 2nd In Temp (C): The temperature at the inlet of the second cold-plate compressor.
Cold 2nd Out Temp (C): The temperature at the outlet of the second cold-plate compressor.
Cold Bottom Temp (C): The temperature at the cold plate’s bottom temperature zone.
Cold Heater:This channel is currently unused.
Cold Mid Bot Temp (C): The temperature at the cold plate’s mid-bottom temperature zone.
Cold Mid Top Temp (C): The temperature at the cold plate’s mid-top temperature zone.
Cold Top Temp (C): The temperature at the cold plate’s top temperature zone.
Cold1 CMP Enable: A Boolean channel that is one if the user has enabled the first cold-plate
compressor and zero otherwise. The user can enable compressors on the Control tab of the
software. Note that for the compressor actually to turn on, it must be enabled and the RPM
speed must be set to a positive value.
Cold2 CMP Enable:A Boolean channel that is one if the user has enabled the second coldplate compressor and zero otherwise. The user can enable compressors on the Control tab of
the software. Note that for the compressor actually to turn on, it must be enabled and the
RPM speed must be set to a positive value.
Cold2 LIQ Sol Bottom: A channel that tells the liquid solenoid pump in the cold-plate’s
bottom temperature-control zone to open and close. This channel is controlled by a PID loop.
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Cold2 LIQ Sol Bottom Loop PID Off Time:The “Off” time in seconds in the current PID loop
for the cold plate’s bottom temperature-control zone. If this number is five and Cold2 LIQ Sol
Bottom PID On Time is ten, the refrigerant will be discharged for ten seconds and then
stopped for five seconds.
Cold2 LIQ Sol Bottom Loop PID Out: A control channel that reflects the user’s selected setpoint temperature in ºC for the cold plate’s bottom temperature-control zone.
Cold2 LIQ Sol Bottom PID On Time: The “On” time in seconds in the current PID loop for the
cold plate’s bottom temperature-control zone. If this number is ten and Cold2 LIQ Sol
Bottom LoopPID Off Time is five, the refrigerant will be discharged for ten seconds and then
stopped for five seconds.
Cold2 LIQ Sol Mid Bot: A channel that tells the liquid solenoid pump in the cold-plate’s midbottom temperature-control zone to open and close. This channel is controlled by a PID loop.
Cold2 LIQ Sol Mid Top: A channel that tells the liquid solenoid pump in the cold-plate’s midtop temperature zone to open and close. This channel is controlled by a PID loop.
Cold2 LIQ Sol Top: A channel that tells the liquid solenoid pump in the cold-plate’s top
temperature zone to open and close. This channel is controlled by a PID loop.
Cold2 LIQ Sol Top Loop PID Off Time: The “Off” time in seconds in the current PID loop for
the cold plate’s top temperature-control zone. If this number is five and Cold2 LIQ Sol Top
PID On Time is ten, the refrigerant will be discharged for ten seconds and then stopped for
five seconds.
Cold2 LIQ Sol Top Loop PID Out:A control channel that reflects the user’s selected set-point
temperature in ºC for the cold plate’s top temperature-control zone.
Cold2 LIQ Sol Top PID On Time:The “On” time in seconds in the current PID loop for the cold
plate’s top temperature-control zone. If this number is ten and Cold2 LIQ Sol Top Loop PID
Off Time is five, the refrigerant will be discharged for ten seconds and then stopped for five
seconds.
Cold2 Mid Bot Loop PID Off Time:The “Off” time in seconds in the current PID loop for the
cold plate’s mid-bottom temperature-control zone. If this number is five and Cold2 Mid Bot
PID On Time is ten, the refrigerant will be discharged for ten seconds and then stopped for
five seconds.
Cold2 Mid Bot Loop PID Out:A control channel that reflects the user’s selected set-point
temperature in ºC for the cold plate’s mid-bottom temperature-control zone.
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Cold2 Mid Bot PID On Time:The “On” time in seconds in the current PID loop for the cold
plate’s mid-bottom temperature-control zone. If this number is ten and Cold2 Mid Bot Loop
PID Off Time is five, the refrigerant will be discharged for ten seconds and then stopped for
five seconds.
Cold2 Mid Top Loop PID Off Time:The “Off” time in seconds in the current PID loop for the
cold plate’s mid-top temperature-control zone. If this number is five and Cold2 Mid Top PID
On Time is ten, the refrigerant will be discharged for ten seconds and then stopped for five
seconds.
Cold2 Mid Top Loop PID Out :A control channel that reflects the user’s selected set-point
temperature in ºC for the cold plate’s mid-top temperature-control zone.
Cold2 Mid Top PID On Time:The “On” time in seconds in the current PID loop for the cold
plate’s mid-top temperature-control zone. If this number is ten and Cold2 Mid Top Loop PID
Off Time is five, the refrigerant will be discharged for ten seconds and then stopped for five
seconds.
Delta Target (C): The temperature difference between the warm and cold plates. For
example, if the warm plate is -20 ˚C and the cold plate is -30 ˚C, Delta Target (C) is 10.
Detector Enabled?: A Boolean indicator that reflects if the detector is enabled. In the SPIN
software, the user can enable or disable the detector using the Detector Controller. Detector
Enabled? will be 1 if the detector is enabled and 0 if it is disabled.
DOF Reject: The number of particles rejected for counting during a given cycle because they
fell outside the instrument’s depth of field. The depth of field is the distance along a laser
beam in which a particle can fall and be sufficiently illuminated and in focus to be sized with
an acceptable level of accuracy.
Drain Timer: A user-settable timer used in the Empty Chamber and Fill & Empty Chamber
sequences.
Dropped PbP Particles: The number of particles rejected for PbP analysis because the system
has recorded too many PbP particles during the current sampling interval.
ED (um): The Effective Diameter of nuclei particles in µm. See the Calculations appendix for
details.
Elapsed Time: The time in seconds that the SPIN program has been running.
Error Code: The LabVIEW-defined error code for the most recent error generated by the
software.
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Evap Cold (C):The temperature at the outlet of the evaporator.
Evap Warm (C):The temperature at the inlet of the evaporator.
Fill Timer: A user-settable timer used in the Fill Chamber and Fill & Empty Chamber
sequences.
H2O Pump Fill /Empty:A control channel that controls the direction of the chamber water
pump. 1 = empty, 0 = fill.
H2O Pump ON:A control channel that determines whether the pump is on or off. 1 = on, 0 =
off. The value of this channel can be determined either by the user or by a sequence.
How Long Min: A parameter used in the Aerosol Controller IV sequence. This parameter sets
the number of minutes the ramp should take to achieve the final parameters set by Aerosol
Target (C) and Delta Target (C). There is no upper limit. However, the number of minutes
needs to be equal or greater than twice the number of degrees that the temperature is
shifting. For example, if the plates are both shifting ten degrees, How Long Min must be at
least 20.
Ice Dwell Counter: A user-settable timer channel that determines the wait time between
filling the chamber and emptying it during the Fill & Empty Chamber sequence.
In Sequence? A Boolean channel that indicates if any sequences are currently running. A
value of 1 means at least one sequence is in progress.
Inlet Pressure Drop:A voltage indicator that reflects the amount of ice build-up on the
sample inlet. If this channel reads between -0.3 and .5 V, the SPIN needs to be warmed and
deiced. Between .5 and 1.5 V is a normal reading during instrument operation.
Input Valve Inlet/Zero:A channel that indicates if the system is sampling ambient air or has
the zero filter on. 1 = sample, 0 = zero.
Internal Temp (C): The temperature of the circuit-board card cage.
Laser Mod SP (V): A controller channel that sets the laser power in Volts.
Laser Pwr Monitor (V):The relative laser power as measured by the laser onboard power
monitor. Note this measurement is actually in arbitrary units, not Volts.
LED COLD PLATE blue:An indicator of the Cold Plate LED’s state. 1 = blue, 0 = red, green or
off. For information on what the LED indicators mean, see section 2.3.
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LED WARM PLATE blue:An indicator of the Warm Plate LED’s state. 1 = blue, 0 = red, green,
or off. For information on what the LED indicators mean, see section 2.3.
Liquid Level 1:A channel indicating if water has reached Level 1 inside the chamber. Level 1
and level 2 are located at the top of the chamber. When water has reached these levels, the
chamber has been filled and can be drained. 1 = water is at level 1, 0 = water has not reached
this level.
Liquid Level 2:A channel indicating if water has reached Level 2 inside the chamber. Level 2,
like level 1, is located at the top of the chamber. When water has reached levels 1 and 2, the
chamber has been filled and can be drained. 1 = water is at level 2, 0 = water has not reached
this level.
Liquid Level 3: A channel indicating if water has reached Level 3 inside. Level 3 is near the
bottom of the chamber. When water has reached level 3,it means water is collecting just
above the optics. The STATUS light will turn red, indicating that the chamber should be
emptied and purged to avoid damage to the optics. To do this, run the Empty Chamber
sequence, and while the sequence is running run the Purge sequence.
MVD (um): The median volume diameter of binned particles. See the Calculations appendix
for calculation details.
Number of Purges: A counter for the number of purges in the Purge sequence.
Output Valve Sample/Fill:A control channel that determines the setting for the valve at the
bottom of the chamber. The default setting is “Sample,” which means air is flowing through
to the chamber. 1= sample, 0 = fill.
P liq Cold Wall (mBar): The vapor pressure of water over ice at the temperature of the Cold
Wall.
P liq Warm Wall (mBar): The vapor pressure of water over ice at the temperature of the
Warm Wall.
P Water Sample (mBar):
(mBar).
The average of P liq Cold Wall (mBar) and P liqWarm Wall
P1 / Size: The average ratio of the P1 signal to the sizing detector signal. This channel is
calculated by summing all the ratios first and then obtaining an average, as follows:
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n
 ( P1 / Size )
i 1
i
i
n
where
n
P1i
Sizei
=
=
=
the total number of qualified PbP particles
the P1 signal for particle i
the Size signal for particle i
P1 High Gain Baseline (V): The average voltage registered by the P1 detector’s high-gain
signal. This voltage is the sum of voltage generated by any scattered particle light and the
voltage offset that the system constantly adds to reduce noise. In situations where no
particles are present, this channel should stay relatively constant and reflect only the voltage
offset.
P1 Low Gain Baseline (V): The average voltage registered by the P1 detector’s low-gain
signal. This voltage is the sum of voltage generated by any scattered particle light and the
voltage offset that the system constantly adds to reduce noise. In situations where no
particles are present, this channel should stay relatively constant and reflect only the voltage
offset.
P1 Overflow: The number of particles that saturated the P1 detector.
P1 Rejects:The number of particles detected by the P1 detector but rejected for PbP analysis
because their P1 signal was too low.
P2 / Size: The average ratio of the P2 signal to the sizing detector signal. This channel is
calculated by summing all the ratios first and then obtaining an average (see P1/Size).
P2 High Gain Baseline (V): The average voltage registered by the P2 detector’s high-gain
signal. This voltage is the sum of voltage generated by any scattered particle light and the
voltage offset that the system constantly adds to reduce noise. In situations where no
particles are present, this channel should stay relatively constant and reflect only the voltage
offset.
P2 Low Gain Baseline (V):The average voltage registered by the P2 detector’s low-gain
signal. This voltage is the sum of voltage generated by any scattered particle light and the
voltage offset that the system constantly adds to reduce noise. In situations where no
particles are present, this channel should stay relatively constant and reflect only the voltage
offset.
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P2 Overflow: The number of particles that saturated the P2 detector.
P2 Rejects: The number of particles detected by the P2 detector but rejected for PbP
analysis because their P2 signal was too low.
Power Supply Curr (A):The power supply for the SPIN system.
Purge:A channel indicating whether the SPIN is currently in purge mode. 1 = purge, 0 =
another mode. When the SPIN is in Purge mode, excess water is draining from the chamber.
Purge modes are used in two situations: after the chamber has been filled and iced, or after
the chamber has been warmed up.
S1 / P1: The average ratio of the S1 to P1 signals. This channel is calculated in the same
manner as P1/Size —that is, summing the ratios first and then obtaining an average.
S1 / P2: The average ratio of the S1 to P2 signals. This channel is calculated by summing the
ratios first and then obtaining an average.
S1 / size: The average ratio of the backscatter 2 signal to the sizing detector signal. This
channel is calculated by summing the ratios first and then obtaining an average.
S1 High Gain Baseline (V): The average voltage registered by the S1 detector‘s high-gain
signal. This voltage is the sum of voltage generated by any scattered particle light and the
voltage offset that the system constantly adds to reduce noise. In situations where no
particles are present, this channel should stay relatively constant and reflect only the voltage
offset.
S1 Low Gain Baseline (V): The average voltage registered by the S1 detector‘s low-gain
signal. This voltage is the sum of voltage generated by any scattered particle light and the
voltage offset that the system constantly adds to reduce noise. In situations where no
particles are present, this channel should stay relatively constant and reflect only the voltage
offset.
S1 Overflow: The number of particles that saturated the S1 detector.
S1 Rejects: The number of particles detected by the S1 detector but rejected for PbP
analysis because their S1 signal was too low.
Sample Flow Signal (V):The voltage reading of the actual sample flow. This voltage ranges
from 0 to 5V and reports the full range of possible flow values. The sample flow can be as
large as 2 lpm, which equates to 5 V. The default flow value is 1 lpm, which means Sample
Flow Signal (V) will be around 2.5 V.
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Sample Flow SP (slpm):The sample flow set point in standard liters per minute.
Sample Pump ON:A Boolean channel set to 1 if the sample pump is on and 0 otherwise.
Sheath Flow Signal (V):The voltage reading of the actual sheath flow. This voltage ranges
from 0 to 5V and reports the full range of possible flow values. The sheath flow can be as
large as 20 lpm, which equates to 5 V. The default flow value is 10 lpm, which means Sheath
Flow Signal (V) will be around 2.5 V.
Sheath Flow SP (slpm):The sheath flow set point in standard liters per minute.
Sheath Pump ON:A Boolean channel set to 1 if the sample pump is on and 0 otherwise.
Size High Gain Baseline (V): The average voltage registered by the sizing detector’s high-gain
signal. This voltage is the sum of voltage generated by any scattered particle light and the
voltage offset that the system constantly adds to reduce noise. In situations where no
particles are present, this channel should stay relatively constant and reflect only the voltage
offset.
Size Low Gain Baseline (V) : The average voltage registered by the sizing detector’s lowgain signal. This voltage is the sum of voltage generated by any scattered particle light and
the voltage offset that the system constantly adds to reduce noise. In situations where no
particles are present, this channel should stay relatively constant and reflect only the voltage
offset.
Size Overflow:The number of particles that saturated the sizing (side-scatter) optics.
Size PbP Rejects:The number of particles detected by the sizing (side-scatter) optics but
rejected for PbP analysis because their size signal was too low.
Slope Cycle Time (sec): A parameter used in the Aerosol Controller IV sequence that
determines the number of seconds between each step change in temperature. This value is
usually set to 15 – 30 seconds.
SS% Ice: The supersaturationrate for ice. See the calculations appendix for details.
SS% Water:The supersaturationrate for water. See the calculations appendix for details.
Sum of Transit:
The number of 12.5-nanosecond intervals during which a particle was
illuminated by the side-scattering (sizing) optics.
Time (sec):The time in seconds since midnight local time of the day when the program was
started. Time (sec) channel is reset at midnight if the program is set so that a new file starts
at midnight.
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Timestamp:The seconds since midnight LOCAL time when the current buffer of data was
acquired. (All events obtained within one buffer will have the same Time Stamp.) If you are
acquiring data over midnight and do not start a new data folder, the midnight offset is not
reset. Thus, in this case, after 23:59:59.2 (or 86399.2 seconds since midnight), the Time
Stamp (sec) will increment to 24:00:00.2, then 24:00:01.2, and so on (rather than resetting to
00:00:00).
Total Particles: The total number of particles.
Unused 1 – 5: Unused channels.
VolConc (g/m^3): The volume concentration of particles in grams per cubic meter.
Warm Bottom Temp (C):The temperature at the warm plate’s bottom temperature zone.
Warm Bypass Sol:A control channel that is one when the warm-plate solenoid pump is
delivering refrigerant to the bypass circuit. On the warm plate, unlike the cold plate, the
refrigerant is not simply turned off, but it enters a bypass circuit that returns the refrigerant.
Warm Bypass Sol will always have the opposite value of Warm LIQ Sol.
Warm CMP Enable:A Boolean channel that is one if the user has enabled the warm-plate
compressor and zero otherwise. The user can enable compressors on the Control tab of the
software. Note that for the compressor actually to turn on, it must be enabled and the RPM
speed must be set to a positive value.
Warm Cmpr (RPM):The rotations per minute of the warm-plate compressor.
Warm Cmpr Fault:A Boolean value that is 1 if the warm-plate compressor has faulted. See
the following section, “Fault Conditions,” for more information.
Warm CmprInPres (psi):The pressure on the inlet of the warm-plate compressor. This reading
should be approximately 0-20 psi when the compressor is functioning.
Warm Cmpr In Temp (C):The temperature at the inlet of the warm-plate compressor.
Warm CmprOutPres (psi):The pressure on the outlet of the warm-plate compressor. This
reading should be approximately 80-300 psi when the compressor is functioning.
Warm Cmpr Out Temp (C):The temperature at the inlet of the warm-plate compressor.
Warm Cmpr SP (RPM):The set-point number of rotations per minute for the warm-plate
compressor.
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Warm Heater:This channel is currently unused.
Warm LIQ Sol:A channel that tells the liquid solenoid pump in the warm-plate’s temperature
zone to open and close. This channel is controlled by a PID loop.
Warm Loop PID Off Time (s):The “Off” time in seconds in the current PID loop for the warm
plate’s temperature zone. If this number is five and Warm PID On Time (s) is ten, the
refrigerant will be discharged for ten seconds and then stopped for five seconds.
Warm Loop PID Out: A control channel that reflects the user’s selected set-point
temperature for the warm plate.
Warm Mid Bot Temp (C):The temperature at the warm plate’s mid-bottom temperature
zone.
Warm Mid Top Temp (C):The temperature at the warm plate’s mid-top temperature zone.
Warm PID On Time (s):The “On” time in seconds in the current PID loop for the warm plate’s
temperature zone. If this number is ten and Warm Loop PIDOff Time (s) is five, the
refrigerant will be discharged for ten seconds and then stopped for five seconds.
Warm Top Temp (C):The temperature at the warm plate’s top temperature zone.
Fault Conditions
Compressor faults are triggered by the following conditions:








Over Current
Over Voltage
Under Voltage
Controller Overheat
Motor Overheat
Stalled
Low Speed
Startup failed
Source: “Brushless DC Motor Controller Product Specification Assembly 025A0145,” Document
600A0683, Rev C. Published by Masterflux by Tecumseh, 2009.
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PbP Files
The PbP file names start with SPIN PbP. These files contain particle-by-particle data. For
each recorded particle, the SPIN stores the following channels:
Time Stamp
Size [counts]
P2 [counts]
S1 [counts]
P1 [counts]
Note that there may be multiple PbP files associated with a single SPIN data *.csv file. This is
so that PbP files remain a manageable size and can be opened with multiple applications. Pbp
files will all have the same time stamp as the *.csv file, but will have a suffix that indicates
their order in the sequence:
SPIN007 PbP20120201152015 x1.csv
SPIN007 PbP20120201152015 x2.csv
…
SPIN007 PbP20120201152015 x10.csv
and so on.
*.log File
The log file is a text file that contains a log of all the errors and events encountered while the
SPIN program was running. It notes the time of each error and event. Events include the time
the program was started, the time data acquisition started, the time the housekeeping
program started, alarm conditions that occurred, notes sent to the log file by the operator,
and other actions taken by the program.
*.ini Files
The *.ini file stores configuration settings. It is a text file that is updated when the user
changes settings in the Config tab and then hits Save Changes. This file is stored in
C:\DMT\SPIN Support\.Copies of the config file used during any given session are also
stored in the relevant C:\DMT\SPINData\ directory.
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Appendix D: Calculations for Derived Channels
Effective Diameter: The SPIN software calculates the Effective Diameter (ED) in μm of a
sample droplet spectrum as follows:
n
ED 
p
i 1
n
p
i 1
i
 ri3
i
 ri
2
2
where
n
pi
ri
=
=
=
the number of sizing bins (e.g., 20 on a SPIN with 1-20 bins)
the particle count for bin i
the mean radius in μm of bin i
MVD (Median Volume Diameter) in μm
Most of the information in this section has been copied with permission from the FAA’s
Electronic Aircraft Icing Handbook. The relevant section of the handbook is available online
by clicking on the cldpar.doc link at
airportaircraftsafetyrd.tc.faa.gov/Programs/FlightSafety/icing/eaihbk.htm.
Assume a sample droplet spectrum from an icing cloud for a given time interval is available in the
following form: n sizing bins are defined by the bin boundaries b1, b2, b3, …, bn, bn+1, (in μm) so
that bin 1 is from b1 to b2, bin 2 is from b2 to b3, …, bin n is from bn to bn+1. The bin droplet
concentrations for the icing interval have been determined to be ci droplets per m3 for i = 1, …, n.
Let mi be the midpoint of the ith bin, i = 1, 2, …, n.
mi 
bi  bi 1
2
Let LWC be the total liquid water content for the sample, and LWCi be the liquid water content for
the droplets in the ith bin. (See LWC entry for details.)
Let proi = the proportion of the spectrum LWC that falls in the ith bin.
proi 
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LWCi
LWC
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Let cumi = the cumulative proportion of the spectrum LWC that falls in the first i bins.
cumi  pro1  ...  proi
The median volume diameter (MVD) is defined as the droplet diameter which divides the total
water volume in the droplet spectrum such that half the water volume (or liquid water content) is
in smaller drops and half is in larger drops. It can be approximated by a linear interpolation with
respect to the liquid water content in the (i+1)st bin as follows:
Let i* = the smallest value of i such that cumi*> .5. Then:
 .5  cumi * 1 
(bi * 1  bi * )
MVD  bi *  
proi *


Note that this interpolation gives a more accurate estimate of the median diameter than you
would get by simply taking the halfway point between bi* and bi*1 . The second component of the
 .5  cumi * 1 
(bi * 1  bi * ) , scales the amount being summed to bi* according to how
proi *


equation, 
close bi* and bi*1 each were to .5. If bi* was much closer to .5, for instance, then MVD will be
much closer to the median diameter of the ith bin than to that of the (i+1)th bin.
Table 1 illustrates the computation of the LWC and MVD for a hypothetical instrument.
Bin
Bin Droplet
Number Boundaries
Conc Midpoint
i
bi
ci
mi
LWCi
proi
cumi
3
3
(microns) (per m ) (microns)
(g/m )
1
10 100000
15 0.00018 0.00058 0.00058
2
20 200000
25 0.00164 0.00538 0.00596
3
30 300000
35 0.00673 0.02214 0.02810
4
40 400000
45 0.01909 0.06274 0.09084
5
50 500000
55 0.04356 0.14320 0.23404
6
60 400000
65 0.05752 0.18909 0.42313
7
70 300000
75 0.06627 0.21786 0.64099
8
80 200000
85 0.06431 0.21143 0.85242
9
90 100000
95 0.04489 0.14758 1.00000
10
100
0
105 0.00000 0.00000 1.00000
LWC =
0.30 g/m3
110
MVD = 73.5m
Table 1: Calculating LWC and MVD
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b1 = 10, b2 = 20, …, b11 = 110
c1 = 100,000/m3, c2 = 200,000/m3, …, c10 = 0
m1 = 15, m2 = 25, …, m10 = 95
LWC1 = .00018 g/m3, LWC2 = .00164 g/m3, …, LWC10 = 0 g/m3
Pro1 = .000581, Pro2 = .000538, …, Pro10 = 0
Cum1 = .00058, Cum2 = .00596, …, Cum10 = 1.00000
For this example, i* = 7 and
 .5  .42313 
MVD  70  
(80  70)
 .21786 
Figure 50 shows the LWC (on the left vertical axis) and the cumulative proportion of LWC (on the
right vertical axis) plotted against the bin right endpoint on the horizontal axis: i.e., LWC1 and
cum1 vs. d2, LWC2 and cum2 vs. d3, …, LWC10 and cum10 vs. d11.
When plotted in this way, the MVD is the point in the diameter on the horizontal axis where the
cumulative LWC on the right vertical axis reaches 50 percent of the total.
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Figure 50: Hypothetical LWC and cum(i) Data
SS% Ice is calculated as follows:
SS% Ice = ([(P Water Sample (mbar) / Pice] * 100) - 100
where
P Water Sample (mbar) = the average of the two pressures specified by P liq
Cold Wall (mbar) and P liq Warm Wall (mbar)
Pice = the vapor pressure of water over ice at Tave, whereTave is the average of
the Cold and Warm Wall temperatures.
SS% Water is calculated as follows:
SS% Water = ([(P Water Sample (mbar) / Pwater] * 100) - 100
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where
P Water Sample (mbar) = the average of the two pressures specified by P liq
Cold Wall (mbar) and P liq Warm Wall (mbar)
Pice = the vapor pressure of water over water at T ave, whereTave is the average
of the Cold and Warm Wall temperatures.
Appendix E: SPIN Actions
The SPIN can be programmatically controlled using numerous actions. The software permits
these actions to be used via Alarmsor Sequences. (The SPIN can also be programmatically
controlled by receiving commands remotely via the Common Command Language (CCL); see
Appendix E for details.)
A complete list of SPIN actions and what they do appears below.
Action
Alarm (A) or
Sequence (S)
Add Channels
S
Add to Channel
A, S
Alert
A
Copy Channel
S
Divide Channel
S
Goto
S
Increment Channel
A, S
Log
S
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Description
Adds the Target Channel and the Source and
stores the Result in the Target Channel.
Adds the value specified by the Value
parameter to the Target Channel.
Sets the Target Alarm to true if the condition
specified by the Condition, Channel,
Threshold, Hysteresis, and Min Time is met.
Thisensures that the Alarm Status indicator at
the top of the main program display turns
redand that the alarm condition is noted in the
log file and Alarm Notes. No other action is
taken.
Copies Source channel value to Target Channel.
Divides Target Chanel by Source Channel and
stores the result in Target Channel.
Jumps to the Step of the same Sequence
defined by the Target Label parameter. Goto
cannot be used to jump into another Sequence.
Increase the Target Channel by one.
Writes the Sequence Label to the Log File with a
time stamp.
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Set Ch to Manual
A, S
Start Sequence
A, S
Start Writing Data
A, S
Stop and Reboot
A, S
Stop and Shutdown
A, S
Stop Program
A, S
Multiplies Source Channel and Target Channel
and stores the result in Target Channel.
Restarts the SPIN software with any new
configuration settings applied.
Allows user to redefine an alarm threshold for a
given alarm. This effectively allows the alarm to
be enabled or disabled at different times by
setting the threshold to a value (such as Inf or
-Inf) that can never be obtained.
Sets the channel in Target Channel to the value
in Set Value.
Sets the Target Channel to Control Loop mode,
wherein the units of the Set Point are in units of
the Process Variable Channel.
Sets the Target Channel to Manual mode,
wherein the Set Point is in units of the output
channel.
Starts the specified sequence.
Starts data recording. Note: Make sure file autonaming is enabled for this command to work
properly; see the Acquisition tab in the Config
tab.
Stops the SPIN software and reboots the
computer. This will not automatically restart
the SPIN software after the computer reboots.
If that is desired, it must be configured in the
OS.
Stops the SPIN software and shuts down the
computer.
Stops the SPIN software.
Stop Sequence
A, S
Stops the specified sequence.
Stop Writing Data
A, S
Subtract Channels
S
Wait (Channel)
S
Wait (Value)
S
Stops data recording.
Subtracts the Source Channel from the Target
Channel and stores the result in the Target
Channel.
Waits n seconds before executing the next
Sequence Step, where n is defined by the
current value of the Source Channel.
Waits n seconds before executing the next
Sequence Step, where n is defined by the Value
parameter.
Multiply
S
Restart Program
A, S
Set Alarm Thresh
A, S
Set Channel
A, S
Set Ch to Control
A, S
Appendix F: Remote Communication Format via CCL
The SPIN offers serial communication via the common command language (CCL). The serial
communications is 8-N-1 with no handshaking. The baud rate is 115,200.
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The CCL commands are given in the table below. The following general rules apply to CCL
commands:





Both Commands and Responses always end in a carriage return followed by a line feed
(<CR><LF>).
Commands that return a response end in a “?”.
Commands can be sent in smalls or caps and are converted to uppercase internally.
“True” values can be sent as any of the following: T, t, TR, tr, TRU, tru, TRUE, True,
Y, Yes, 1, ON, On.
“False” values can be sent as any of the following: F, f, FA, fa, FAL, fal, FALS, fals,
FALSE, False, N, No, 0, OFF, Off.
Command from PC
ADD:channel:xx.xx<CR><L
F>
COMPREBOOT<CR><LF>
COMPSHUTDOWN<CR><LF>
EXIT<CR><LF>
GET?:channel<CR><LF>
GETCONTROL? <CR><LF>
IDN?<CR><LF>
INCR:channel<CR><LF>
LOG:text<CR><LF>
Parameter
Channel
(string),
xx.xx(DBL)
Response from
SPIN
Value(DBL)<CR><LF
>
OK<CR><LF>
OK<CR><LF>
OK<CR><LF>
channel
(string)
value
(DBL)<CR><LF>
channel
(string)
True/False<CR>
<LF>
DMT SPIN Software
Version x.x, Serial
Number x.
OK<CR><LF>
OK<CR><LF>
text
(string)
RECORD:True<CR><LF>
OK<CR><LF>
RECORD:False<CR><LF>
OK<CR><LF>
RECORD?<CR><LF>
RESTART<CR><LF>
True/False<CR>
<LF>
OK<CR><LF>
SET:channel:xx.xx<CR>
<LF>
channel
(string),
Value
(DBL)
OK<CR><LF>(no
error if channel not
found)
SETALARM:channel:xx.xx<
CR><LF>
channel
(string),
Value
(DBL)
OK<CR><LF>(no
error if channel not
found)
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Description
Sets channel to the sum of channel
and xx.xx.
Exits the SPIN program and reboots.
Shuts computer down.
Exits the SPIN program.
Returns the value in channel.
Returns an error if the channel is
not found.
Returns False if the controller
channel is in Manual mode, True if it
is in Control Loop mode.
Returns version numbers.
Sets channel to channel + 1.
Enters text in the log file.
Commands the instrument to begin
data recording.
Commands the instrument to stop
data recording.
Queries the instrument as to
whether it is recording; returns True
if it is, False otherwise.
Restarts the SPIN program.
Sets channel to the value xx.xx.
Allows user to redefine an alarm
threshold (xx.xx) for a given alarm.
This effectively allows the alarm to
be enabled or disabled at different
times by setting the threshold to a
value (such as Inf or
-Inf) that can never be obtained.
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Command from PC
Parameter
Response from
SPIN
SETTOCONTROL<CR><LF>
channel
(string)
OK<CR><LF>
SETTOMANUAL<CR><LF>
channel
(string)
OK<CR><LF>
Description
Sets a controller Channel to Control
Loop mode, wherein the units of the
Set Point are in units of the Process
Variable Channel.
Sets a controller Channel to Manual
mode, wherein the Set Point is in
units of the output channel.
STARTSEQ:seq
seq(string)
OK<CR><LF>
Starts the seq sequence.
STOPSEQ:seq
seq(string)
OK<CR><LF>
Stops the seq sequence.
Any command other than those listed above will generate an “?Invalid Command” response
from the SPIN.
Appendix G: Syntax for Calculated Channels
The Config > Calculations tab allows users to create and calculate their own channels using
the Calculated Channels controls. The table below describes the syntax for the available
functions. These functions can be used in the Formula parameter.
Function Syntax
Function Name
Description
abs(x)
Absolute Value
Returns the absolute value of x.
acos(x)
Inverse Cosine
Computes the inverse cosine of x.
acosh(x)
Inverse Hyperbolic Cosine
Computes the inverse hyperbolic cosine
of x in radians.
asin(x)
Inverse Sine
Computes the inverse sine of x in radians.
asinh(x)
Inverse Hyperbolic Sine
Computes the inverse hyperbolic sine of x
in radians.
atan(x)
Inverse Tangent
Computes the inverse tangent of x in
radians.
atanh(x)
Inverse
Tangent
ci(x)
Cosine Integral
Computes the cosine integral of xwhere
xis any real number.
ceil(x)
Round to +Infinity
Rounds x to the next higher integer
(smallest integer >=x.)
cos(x)
Cosine
Computes the cosine of x in radians.
cosh(x)
Hyperbolic Cosine
Computes the hyperbolic cosine of x in
radians.
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Hyperbolic Computes the inverse hyperbolic tangent
of x in radians.
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Function Syntax
Function Name
Description
cot(x)
Cotangent
Computes the cotangent of x in radians
(1/tan(x)).
csc(x)
Cosecant
Computes the cosecant of x in radians
(1/sin(x)).
exp(x)
Exponential
Computes the value of eraised to the
power x.
expm1(x)
Exponential(Arg)—1
Computes the value of e raised to the
power of x— 1 (ex– 1).
floor(x)
Round to —Infinity
Truncates x to the next lower integer
(Largest integer <=x)
gamma(x)
Gamma Function
Г(n + 1) = n!for all natural numbers n.
getexp(x)
Mantissa and exponent
Returns the exponent of x.
getman(x)
Mantissa and exponent
Returns the mantissa of x.
int(x)
Round to nearest integer
Rounds its argument to the nearest even
integer.
intrz
Round toward zero
Rounds x to the nearest integer between
x and zero.
ln(x)
Natural Logarithm
Computes the natural logarithm of x (to
the base e).
Inpl(x)
log(x)
Natural Logarithm (Arg+1)
Logarithm Base 10
log2(x)
Logarithm Base 2
pi(x)
Represents the value
π = 3.14159
rand()
Random Number (0—1)
sec(x)
si(x)
Secant
Sine Integral
sign(x)
Sign
sin(x)
sinc(x)
Sine
Sinc
sinh(x)
Hyperbolic Sine
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Computes the natural logarithm of(x+1).
Computes the logarithm of x (to the base
10).
Computes the logarithm of x (to the base
2).
pi(x) = x * π
pi(1)= π
pi(2.4) = 2.4* π
Produces
a
floating-point
number
between 0 and 1.
Computes the secant of x (1/cos(x)).
Computes the sine integral of x where xis
any realnumber.
Returns 1 if x is greater than 0.
Returns 0 if xx is equal to 0.
Returns -1 if x is less than 0.
Computes the sine of x in radians.
Computes the sine of x divided by x in
radians (sin(x)/x).
Computes the hyperbolic sine of x in
radians.
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Function Syntax
spike(x)
Function Name
Spike function
sqrt(x)
square(x)
Square Root
square(x)
step(x)
Step function
tan(x)
tanh(x)
Tangent
Hyperbolic Tangent
Description
Returns:
1
if
0
<=x<=1
0 for any other value of x.
Computes the square root of x.
square (x) returns:
1 if 2n<= x<= (2n +1)
0 if 2n + 1 <= x<= (2n +2)
where x is any real number and
nis any integer.
step(x) returns:
0 if x < 0
1 if any other condition applies.
Computes the tangent of x in radians.
Computes the hyperbolic tangent of x in
radians.
The above table is largely excerpted from the G Math Toolkit Reference Manual produced by
National Instruments. A complete version is available online.
Appendix H: Refrigerant Information
The three refrigeration systems each contain varying amounts of refrigerant. Depending on
mode of shipping for the SPIN and the requirements, there may be hazardous materials
notification involved. The following table details the amounts and types of refrigerant in the
systems:
Compressor
Warm
Cold 1
Cold 2
Amount of Refrigerant
16 oz
14 oz
14 oz
Type of Refrigerant
R-404A
R-404A
508B
The following pages have additional information about SPIN refrigerants.
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Appendix I: Compressor Controller--Specifications
Please see the following pages for product specifications.
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Appendix J: ILS Industrial Laser System Instruction
Manual
Please see the following pages for the Instruction Manual. This manual was provided by Osela,
Inc. of Quebec, Canada.
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Appendix K: Aerosol Controller Plot
The graph below demonstrates the functionality of the Aerosol Controller IV sequence. In this
situation, the SPIN started with an Aerosol Target of -25 ˚C and a Delta Target of 0 ˚C. The
user then kept the Aerosol Target constant but changed Delta Target to 20 ˚C, causing a
diverging ramp. Next, the Delta Target was kept constant at 20 ˚C while the Aerosol Target
was decreased, causing a downward aerosol ramp.
Figure 51: Shifting Temperatures with the Aerosol Controller IV Sequence
Appendix L: Revisions to Manual
Rev. Date
Rev No.
Summary
8-8-2012
B
12-13-12
B-1
12-28-12
B-2
Added pictures of instrument
Updated output channel names to reflect software
changes
Added section on shut-down sequences
Added section on PbP data files
Added appendices on refrigerants and compressor
controller
Inserted picture of new SPIN
Enlarged labels on photographs
Updated specifications
Inserted ILS Industrial Laser System Instruction Manual
Added information about the Aerosol Controller IV
sequence
2-11-13
B-3
Corrected citation for Chou et al publication
4-13-11
A-2
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Section
4.1
Appendix C
8.6.1.2
Appendix C
Appendices
H and J
1.0
Throughout
Appendix A
Appendix J
8.2.2,
Appendices
C and K
2.0
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