RedLab TEMP
USB-based High-Precision 8-Channel
Temperature Measurement Module
User's Guide
Document Revision 1.5 E, April, 2014
© Copyright 2014, Meilhaus Electronic
Imprint
User’s Guide RedLab® Series
Document Revision 1.5 E
Revision Date: April 2014
Meilhaus Electronic GmbH
Am Sonnenlicht 2
D-82239 Alling near Munich, Germany
http://www.meilhaus.de
© Copyright 2014 Meilhaus Electronic GmbH
All rights reserved. No part of this publication may be reproduced, stored in a retrieval system, or
transmitted, in any form by any means, electronic, mechanical, by photocopying, recording, or
otherwise without the prior written permission of Meilhaus Electronic GmbH.
Important note:
All the information included in this user’s guide were put together with utmost care and to best
knowledge. However, mistakes may not have been erased completely.
For this reason, the firm Meilhaus Electronic GmbH feels obliged to point out that they cannot be take
on neither any warranty (apart from the claims for warranty as agreed) nor legal responsibility or
liability for consequences caused by incorrect instructions.
We would appreciate it if you inform us about any possible mistakes.
The trademark Personal Measurement Device, TracerDAQ, Universal Library, InstaCal, Harsh
Environment Warranty, Measurement Computing Corporation, and the Measurement Computing logo
are either trademarks or registered trademarks of Measurement Computing Corporation.
Windows, Microsoft, and Visual Studio are either trademarks or registered trademarks of Microsoft
Corporation.
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All other trademarks are the property of their respective owners.
3
Table of Contents
Preface
About this User’s Guide .......................................................................................................................6
What you will learn from this user’s guide.........................................................................................................6
Conventions in this user’s guide.........................................................................................................................6
Where to find more information .........................................................................................................................6
Chapter 1
Introducing the RedLab TEMP.............................................................................................................7
Overview: RedLab TEMP features.....................................................................................................................7
RedLab TEMP block diagram ............................................................................................................................8
Software features ................................................................................................................................................8
Connecting a RedLab TEMP to your computer is easy......................................................................................9
Chapter 2
Installing the RedLab TEMP...............................................................................................................10
What comes with your RedLab TEMP shipment? ...........................................................................................10
Hardware .........................................................................................................................................................................10
Additional documentation................................................................................................................................................10
Unpacking the RedLab TEMP..........................................................................................................................10
Installing the software ......................................................................................................................................11
Installing the RedLab TEMP ............................................................................................................................11
Configuring the RedLab TEMP........................................................................................................................12
Calibrating the RedLab TEMP .........................................................................................................................12
Chapter 3
Sensor Connections ...........................................................................................................................13
Screw terminal pin out......................................................................................................................................13
Sensor input terminals (C0H/C0L to C7H/C7L)..............................................................................................................14
Current excitation output terminals (±I1 to ±I4) ..............................................................................................................15
Four-wire, two sensor common terminals (4W01 to 4W67)............................................................................................15
Two sensor common terminals (IC01 to IC67)................................................................................................................15
Ground terminals (GND) .................................................................................................................................................15
Power terminals (+5V).....................................................................................................................................................15
Digital terminals (DIO0 to DIO7)....................................................................................................................................15
CJC sensors......................................................................................................................................................................15
Thermocouple connections...............................................................................................................................15
Wiring configuration........................................................................................................................................................15
RTD and thermistor connections ......................................................................................................................16
Two-wire configuration ...................................................................................................................................................17
Three-wire configuration .................................................................................................................................................18
Four-wire configuration ...................................................................................................................................................18
Semiconductor sensor measurements ...............................................................................................................20
Wiring configuration........................................................................................................................................................20
Digital I/O connections.....................................................................................................................................21
Chapter 4
Functional Details ...............................................................................................................................22
Thermocouple measurements ...........................................................................................................................22
Cold junction compensation (CJC) ..................................................................................................................................22
Data linearization.............................................................................................................................................................22
Open-thermocouple detection (OTD) ..............................................................................................................................22
RTD and thermistor measurements ..................................................................................................................23
Data linearization.............................................................................................................................................................23
USB connector..................................................................................................................................................23
4
RedLab TEMP User's Guide
LED ..................................................................................................................................................................23
Power................................................................................................................................................................24
Chapter 5
Specifications......................................................................................................................................25
Analog input .....................................................................................................................................................25
Channel configurations.....................................................................................................................................26
Compatible sensors...........................................................................................................................................26
Accuracy...........................................................................................................................................................27
Thermocouple measurement accuracy .............................................................................................................................27
Semiconductor sensor measurement accuracy .................................................................................................................28
RTD measurement accuracy ............................................................................................................................................28
Thermistor measurement accuracy ..................................................................................................................................28
Throughput rate ................................................................................................................................................29
Digital input/output...........................................................................................................................................30
Memory ............................................................................................................................................................30
Microcontroller.................................................................................................................................................30
USB +5V voltage .............................................................................................................................................30
Power................................................................................................................................................................31
USB specifications ...........................................................................................................................................31
Current excitation outputs (Ix+) .......................................................................................................................32
Environmental ..................................................................................................................................................32
Mechanical .......................................................................................................................................................32
Screw terminal connector type and pin out.......................................................................................................32
Screw terminal pin out .....................................................................................................................................................33
5
Preface
About this User’s Guide
What you will learn from this user’s guide
This user’s guide explains how to install, configure, and use the RedLab TEMP so that you get the most out of
its USB-based temperature measurement features.
This user’s guide also refers you to related documents available on our web site, and to technical support
resources.
Conventions in this user’s guide
For more information on …
Text presented in a box signifies additional information and helpful hints related to the subject matter you are
reading.
Caution! Shaded caution statements present information to help you avoid injuring yourself and others,
damaging your hardware, or losing your data.
<#:#>
Angle brackets that enclose numbers separated by a colon signify a range of numbers, such as those assigned
to registers, bit settings, etc.
bold text
Bold text is used for the names of objects on the screen, such as buttons, text boxes, and check boxes. For
example:
1. Insert the disk or CD and click the OK button.
italic text
Italic text is used for the names of manuals and help topic titles, and to emphasize a word or phrase. For
example:
The InstaCal installation procedure is explained in the Quick Start Guide.
Never touch the exposed pins or circuit connections on the board.
Where to find more information
The following electronic documents provide helpful information relevant to the operation of the RedLab TEMP.
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The Quick Start Guide is available on our RedLab CD in the root directory.
The Guide to Signal Connections is available on our RedLab CD under „ICalUL\Documents“.
The Universal Library User's Guide is available on our RedLab CD under „ICalUL\Documents“.
The Universal Library Function Reference is available on our RedLab CD under „ICalUL\Documents“.
The Universal Library for LabVIEW™ User’s Guide is available on our RedLab CD under
„ICalUL\Documents“.
6
Chapter 1
Introducing the RedLab TEMP
Overview: RedLab TEMP features
This user's guide contains all of the information you need to connect the RedLab TEMP to your computer and
to the signals you want to measure.
The RedLab TEMP is a USB 2.0 full-speed, temperature measurement module that is supported under popular
Microsoft® Windows® operating systems. The RedLab TEMP is fully compatible with both USB 1.1 and USB
2.0 ports.
The RedLab TEMP provides eight differential input channels that are software programmable for different
sensor categories including thermocouple, RTDs, thermistors and Semiconductor sensors. Eight independent,
TTL-compatible digital I/O channels are provided to monitor TTL-level inputs, communicate with external
devices, and to generate alarms. The digital I/O channels are software programmable for input or output.
With the RedLab TEMP, you can take measurements from four sensor categories:
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Thermocouple – types J, K, R, S, T, N, E, and B
Resistance temperature detectors (RTDs) – 2, 3, or 4-wire measurements of 100 Ω platinum RTDs
Thermistors – 2, 3, or 4-wire measurements
Semiconductor temperature sensors – LM36 or equivalent
The RedLab TEMP provides a 24-bit analog-to-digital (A/D) converter for each pair of differential analog input
channels. Each pair of differential inputs constitutes a channel pair.
You can connect a different category of sensor to each channel pair, but you can not mix categories among the
channels that constitute a channel pair (although it is permissible to mix thermocouple types).
The RedLab TEMP provides two integrated cold junction compensation (CJC) sensors for thermocouple
measurements, and built-in current excitation sources for resistive sensor measurements.
An open thermocouple detection feature lets you detect a broken thermocouple. An on-board microprocessor
automatically linearizes the measurement data according to the sensor category.
The RedLab TEMP is a standalone plug-and-play module which draws power from the USB cable. No external
power supply is required. All configurable options are software programmable.
The RedLab TEMP is fully software calibrated.
7
RedLab TEMP User's Guide
Introducing the RedLab TEMP
RedLab TEMP block diagram
RedLab TEMP functions are illustrated in the block diagram shown here.
Precision
5V Ref.
DIO
24-bit A/D
(CH0, CH1)
8
Input
mux.
±Ix
Isolated
Micro
SPI
24-bit A/D
(CH2, CH3)
Temp
sensor
Isolated
DC/DC
USB
+5V
Input
mux.
CJC
CH0-3
(+12)
(-12)
±Ix
24-bit A/D
(CH4, CH5)
Input
mux.
±Ix
500 V
Isolation
Barrier
24-bit A/D
(CH6, CH7)
Input
mux.
Screw Terminal
I/O
Isolator
USB 2.0
Microcontroller
Screw Terminal
±Ix
USB
(PC)
CJC
CH4-7
Figure 1. RedLab TEMP functional block diagram
Software features
For information on the features of InstaCal and the other software included with your RedLab TEMP, refer to
the Quick Start Guide that shipped with your device. The Quick Start Guide is also available in PDF on our
RedLab CD (root directory).
8
RedLab TEMP User's Guide
Introducing the RedLab TEMP
Connecting a RedLab TEMP to your computer is easy
Installing a data acquisition device has never been easier.
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The RedLab TEMP relies upon the Microsoft Human Interface Device (HID) class drivers. The HID class
drivers ship with every copy of Windows that is designed to work with USB ports. We use the Microsoft
HID because it is a standard, and its performance delivers full control and maximizes data transfer rates for
your RedLab TEMP. No third-party device driver is required.
The RedLab TEMP is plug-and-play. There are no jumpers to position, DIP switches to set, or interrupts to
configure.
You can connect the RedLab TEMP before or after you install the software, and without powering down
your computer first. When you connect an HID to your system, your computer automatically detects it and
configures the necessary software. You can connect and power multiple HID peripherals to your system
using a USB hub.
You can connect your system to various devices using a standard four-wire cable. The USB connector
replaces the serial and parallel port connectors with one standardized plug and port combination.
You do not need a separate power supply module. The USB automatically delivers the electrical power
required by each peripheral connected to your system.
Data can flow two ways between a computer and peripheral over USB connections.
9
Chapter 2
Installing the RedLab TEMP
What comes with your RedLab TEMP shipment?
The following items are shipped with the RedLab TEMP.
Hardware
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RedLab TEMP
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USB cable (2 meter length)
Additional documentation
In addition to this hardware user's guide, you should also receive the Quick Start Guide (available on our
RedLab CD (root directory)). This booklet supplies a brief description of the software you received with your
RedLab TEMP and information regarding installation of that software. Please read this booklet completely
before installing any software or hardware.
10
RedLab TEMP User's Guide
Installing the RedLab TEMP
Unpacking the RedLab TEMP
As with any electronic device, you should take care while handling to avoid damage from static
electricity. Before removing the RedLab TEMP from its packaging, ground yourself using a wrist strap or by
simply touching the computer chassis or other grounded object to eliminate any stored static charge.
If your RedLab TEMP is damaged, notify Meilhaus Electronic immediately by phone, fax, or e-mail. For
international customers, contact your local distributor where you purchased the RedLab TEMP.
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Phone: +49 (0) 8141/5271-188
Fax: +49 (0) 8141/5271-169
E-Mail: support@meilhaus.com
Installing the software
Refer to the Quick Start Guide for instructions on installing the software Guide (available on our RedLab CD
(root directory)).
Installing the RedLab TEMP
To connect the RedLab TEMP to your system, turn your computer on, and connect the USB cable to a USB port
on your computer or to an external USB hub that is connected to your computer. The USB cable provides power
and communication to the RedLab TEMP.
When you connect the RedLab TEMP (follow illustrations: USB-TEMP) for the first time, a Found New
Hardware popup balloon (Windows XP) or dialog (other Windows versions) opens as the RedLab TEMP is
detected.
When this balloon or dialog closes, the installation is complete. The USB LED should flash and then remain lit.
This indicates that communication is established between the RedLab TEMP and your computer.
Caution! Do not disconnect any device from the USB bus while the computer is communicating with the
RedLab TEMP, or you may lose data and/or your ability to communicate with the RedLab TEMP.
If the LED turns off
If the LED is lit but then turns off, the computer has lost communication with the RedLab TEMP. To restore
communication, disconnect the USB cable from the computer, and then reconnect it. This should restore
communication, and the LED should turn back on.
11
RedLab TEMP User's Guide
Installing the RedLab TEMP
Configuring the RedLab TEMP
All hardware configuration options on the RedLab TEMP are programmable with software. Use InstaCal to set
the sensor type for each channel. The configurable options dynamically update according to the selected sensor
category. Configuration options are stored on the RedLab TEMP 's isolated microcontroller in EEPROM, which
is non-volatile memory on the RedLab TEMP module. Configuration options are loaded on power up.
Default configuration
The factory default configuration is Disabled. The Disabled mode disconnects the analog inputs from the
terminal blocks and internally grounds all of the A/D inputs. This mode also disables each of the current
excitation sources.
Warm up
Allow the RedLab TEMP to warm up for 30 minutes before taking measurements. This warm up time
minimizes thermal drift and achieves the specified rated accuracy of measurements.
For RTD or thermistor measurements, this warm-up time is also required to stabilize the internal current
reference.
Calibrating the RedLab TEMP
The RedLab TEMP is fully calibrated via software. InstaCal prompts you to run its calibration utility when you
change from one sensor category to another.
Allow the RedLab TEMP to operate for at least 30 minutes before calibrating. This warm up time minimizes
thermal drift and achieves the specified rated accuracy of measurements.
12
Chapter 3
Sensor Connections
The RedLab TEMP supports the following temperature sensor types:
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Thermocouple – types J, K, R, S, T, N, E, and B
Resistance temperature detectors (RTDs) – 2, 3, or 4-wire measurement modes of 100 Ω platinum RTDs.
Thermistors – 2, 3, or 4-wire measurement modes.
Semiconductor temperature sensors – LM36 or equivalent
Sensor selection
The type of sensor you select will depend on your application needs. Review the temperature ranges and
accuracies of each sensor type to determine which is best suited for your application.
Screw terminal pin out
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
I2+
NC
C2H
C2L
4W23
IC23
C3H
C3L
GND
I2+5V
GND
DIO0
DIO1
DIO2
DIO3
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
I3GND
C5L
C5H
IC45
4W45
C4L
C4H
NC
I3+
+5V
GND
DIO7
DIO6
DIO5
DIO4
CJC Sensor
CJC Sensor
I1+
NC
C0H
C0L
4W01
IC01
C1H
C1L
GND
I1-
1
2
3
4
5
6
7
8
9
10
27
28
29
30
31
32
33
34
35
36
I4GND
C7L
C7H
IC67
4W67
C6L
C6H
NC
I4+
The RedLab TEMP has four rows of screw terminals — two rows on the top edge of the housing, and two rows
on the bottom edge. Each row has 26 connections. Between each bank of screw terminals are two integrated
CJC sensors used for thermocouple measurements. Signals are identified in Figure 2.
Figure 2. RedLab TEMP screw terminal pin numbers
13
RedLab TEMP User's Guide
Sensor Connections
RedLab TEMP screw terminal descriptions
Pin
1
2
3
Signal
Name
I1+
NC
C0H
4
C0L
5
6
7
4W01
IC01
C1H
8
C1L
9
10
GND
I1-
Pin Description
Pin
CH0/CH1 current excitation source
Not connected
CH0 sensor input (+)
27
28
29
CH0 sensor input (-)
CH0/CH1 4-wire, 2 sensor common
CH0/CH1 2-sensor common
CH1 sensor input (+)
30
C7H
31
32
33
IC67
4W67
C6L
34
C6H
CH6/CH7 2 sensor common
CH6/CH7 4-wire, 2 sensor common
CH6 sensor input (-)
CH6 sensor input (+)
35
36
NC
I4+
Not connected
CH6/CH7 current excitation source
CH1 sensor input (-)
Ground
CH0/CH1 current excitation return
CJC sensor
Signal
Name
I4GND
C7L
Pin Description
CH6/CH7 current excitation return
Ground
CH7 sensor input (-)
CH7 sensor input (+)
CJC sensor
11
12
13
I2+
NC
C2H
CH2/CH3 current excitation source
Not connected
CH2 sensor input (+)
37
38
39
14
C2L
C5H
4W23
IC23
C3H
CH2 sensor input (-)
CH2/CH3 4-wire, 2 sensor common
CH2/CH3 2 sensor common
CH3 sensor input (+)
40
15
16
17
41
42
43
IC45
4W45
C4L
44
C4H
CH4/CH5 2 sensor common
CH4/CH5 4-wire, 2 sensor common
CH4 sensor input (-)
CH4 sensor input (+)
45
46
47
48
49
50
51
52
NC
I3+
+5V
GND
DIO7
DIO6
DIO5
DIO4
Not connected
CH4/CH5 current excitation source
+5V output
Ground
Digital Input/Output
Digital Input/Output
Digital Input/Output
Digital Input/Output
18
C3L
19
20
21
22
23
24
25
26
GND
I2+5V
GND
DIO0
DIO1
DIO2
DIO3
CH3 sensor input (-)
Ground
CH2/CH3 current excitation return
+5V output
Ground
Digital Input/Output
Digital Input/Output
Digital Input/Output
Digital Input/Output
I3GND
C5L
CH4/CH5 current excitation return
Ground
CH5 sensor input (-)
CH5 sensor input (+)
Use 16 AWG to 30 AWG wire for your signal connections.
Tighten screw terminal connections
When making connections to the screw terminals, be sure to tighten the screw until tight. Simply touching the
top of the screw terminal is not sufficient to make a proper connection.
Sensor input terminals (C0H/C0L to C7H/C7L)
You can connect up to eight temperature sensors to the differential sensor inputs (C0H/C0L to C7H/C7L).
Supported sensor categories include thermocouples, RTDs, thermistors, or semiconductor sensors.
Do not mix sensor categories within channel pairs. You can mix thermocouple types (J, K, R, S, T, N, E, and B)
within channel pairs, however.
Do not connect two different sensor categories to the same channel pair
The RedLab TEMP provides a 24 bit A/D converter for each channel pair. Each channel pair can monitor one
sensor category. To monitor a sensor from a different category, connect the sensor to a different channel pair
(input terminals).
14
RedLab TEMP User's Guide
Sensor Connections
Current excitation output terminals (±I1 to ±I4)
The RedLab TEMP has four dedicated pairs of current excitation output terminals (±I1 to ±I4). These terminals
have a built-in precision current source to provide excitation for the resistive sensors used for RTD and
thermistor measurements.
Each current excitation terminal is dedicated to one pair of sensor input channels:
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I1+ is the current excitation source for channel 0 and channel 1
I2+ is the current excitation source for channel 2 and channel 3
I3+ is the current excitation source for channel 4 and channel 5
I4+ is the current excitation source for channel 6 and channel 7
Four-wire, two sensor common terminals (4W01 to 4W67)
These terminals are used as the common connection for four-wire configurations with two RTD or thermistor
sensors.
Two sensor common terminals (IC01 to IC67)
These terminals are used as the common connection for two-wire configurations with two RTD or thermistor
sensors.
Ground terminals (GND)
The six ground terminals (GND) provide a common ground for the input channels and DIO bits and are isolated
(500 VDC) from the USB GND.
Power terminals (+5V)
The two +5V output terminals are isolated (500 VDC) from the USB +5V.
Digital terminals (DIO0 to DIO7)
You can connect up to eight digital I/O lines to the screw terminals labeled DIO0 to DIO7. Each terminal is
software configurable for input or output.
CJC sensors
The RedLab TEMP has two built in high-resolution temperature sensors. One sensor is located on the right side
of the package, and one sensor is located at the left side.
Thermocouple connections
A thermocouple consists of two dissimilar metals that are joined together at one end. When the junction of the
metals is heated or cooled, a voltage is produced that correlates to temperature.
The RedLab TEMP makes fully differential thermocouple measurements without the need of groundreferencing resistors. A 32-bit floating point value in either a voltage or temperature format is returned by
software. An open thermocouple detection feature is available for each analog input which automatically detects
an open or broken thermocouple.
Use InstaCal to select the thermocouple type (J, K, R, S, T, N, E, and B) and one or more sensor input channels
to connect the thermocouple.
Wiring configuration
Connect the thermocouple to the RedLab TEMP using a differential configuration, as shown in
15
Sensor Connections
I#+
NC
C#H
C#L
4W##
IC##
C#H
C#L
GND
I#-
RedLab TEMP User's Guide
I#+
NC
C#H
C#L
4W##
IC##
C#H
C#L
GND
I#-
Figure 3.
Figure 3. Typical thermocouple connection
The RedLab TEMP GND pins are isolated from earth ground, so connecting thermocouple sensors to voltages
referenced to earth ground is permissible as long as the isolation between the GND pins (9, 19, 28, 38) and earth
ground is maintained.
When thermocouples are attached to conductive surfaces, the voltage differential between multiple
thermocouples must remain within ±1.4 V. For best results, we recommend the use of insulated or ungrounded
thermocouples when possible.
Maximum input voltage between analog input and ground
The absolute maximum input voltage between an analog input and the isolated GND pins is ±25 VDC when the
RedLab TEMP is powered on, and ±40 VDC when the RedLab TEMP is powered off.
If you need to increase the length of your thermocouple, use the same type of thermocouple wires to minimize
the error introduced by thermal EMFs.
RTD and thermistor connections
A resistance temperature detector (RTD) measures temperature by correlating the resistance of the RTD
element with temperature. A thermistor is a thermally-sensitive resistor that is similar to an RTD in that its
resistance changes with temperature — thermistors show a large change in resistance that is proportional to a
small change in temperature. The main difference between RTD and thermistor measurements is the method
used to linearize the sensor data.
RTDs and thermistors are resistive devices that require an excitation current to produce a voltage drop that can
be measured differentially across the sensor. The RedLab TEMP features four built-in current excitation sources
(±I1 to ±I4) for measuring resistive type sensors. Each current excitation terminal is dedicated to one channel
pair.
The RedLab TEMP makes two, three, and four-wire measurements of RTDs (100 Ω platinum type) and
thermistors.
Use InstaCal to select the sensor type and the wiring configuration. Once the resistance value is calculated, the
value is linearized in order to convert it to a temperature value. A 32-bit floating point value in either
temperature or resistance is returned by software.
16
RedLab TEMP User's Guide
Sensor Connections
RTD maximum resistance
Resistance values greater than 660 Ω cannot be measured by the RedLab TEMP in the RTD mode. The 660 Ω
resistance limit includes the total resistance across the current excitation (±Ix) pins, which is the sum of the
RTD resistance and the lead resistances.
Thermistor maximum resistance
Resistance values greater than 180k ohms cannot be measured by the RedLab TEMP in the thermistor mode.
The 180 k Ω resistance limit includes the total resistance across the current excitation (±Ix) pins, which is the
sum of the thermistor resistance and the lead resistance.
Two-wire configuration
The easiest way to connect an RTD sensor or thermistor to the RedLab TEMP is with a two-wire configuration,
since it requires the fewest connections to the sensor. With this method, the two wires that provide the RTD
sensor with its excitation current also measure the voltage across the sensor.
Since RTDs exhibit a low nominal resistance, measurement accuracy can be affected due to the lead wire
resistance. For example, connecting lead wires that have a resistance of 1 Ω (0.5 Ω each lead) to a 100 Ω
platinum RTD will result in a 1% measurement error.
With a two-wire configuration, you can connect either one sensor per channel pair, or two sensors per channel
pair.
Two-wire, single-sensor
I#+
NC
C#H
C#L
4W##
IC##
C#H
C#L
GND
I#-
A two-wire single-sensor measurement configuration is shown in Figure 4.
Figure 4. Two-wire, single RTD or thermistor sensor measurement configuration
When you select a two-wire single sensor configuration with InstaCal, connections to C#H and C#L are made
internally.
17
RedLab TEMP User's Guide
Sensor Connections
Two-wire, two sensor
I#+
NC
C#H
C#L
4W##
IC##
C#H
C#L
GND
I#-
A two-wire, two-sensor measurement configuration is shown in Figure 5.
Figure 5. Two-wire, two RTD or thermistor sensors measurement configuration
When you select a two-wire, two sensor configuration with InstaCal, connections to C#H (first sensor) and
C#H/C#L (second sensor) are made internally.
When configured for two-wire mode, both sensors must be connected to obtain proper measurements.
Three-wire configuration
I#+
NC
C#H
C#L
4W##
IC##
C#H
C#L
GND
I#-
A three-wire configuration compensates for lead-wire resistance by using a single voltage sense connection.
With a three-wire configuration, you can connect only one sensor per channel pair. A three-wire measurement
configuration is shown in Figure 6.
Figure 6. Three-wire RTD or thermistor sensor measurement configuration
When you select a three-wire sensor configuration with InstaCal, the RedLab TEMP measures the lead
resistance on the first channel (C#H/C#L) and measures the sensor itself using the second channel (C#H/C#L).
This configuration compensates for any lead-wire resistance and temperature change in lead-wire resistance.
Connections to C#H for the first channel and C#H/C#L of the second channel are made internally.
Three-wire compensation
For accurate three wire compensation, the individual lead resistances connected to the ±I# pins must be of equal
resistance value.
Four-wire configuration
With a four-wire configuration, connect two sets of sense/excitation wires at each end of the RTD or thermistor
sensor. This configuration completely compensates for any lead-wire resistance and temperature change in leadwire resistance.
Connect your sensor with a four-wire configuration when your application requires very high accuracy
measurements. Examples of a four-wire single-sensor measurement configuration are shown in Figure 7 and
Figure 8.
You can configure the RedLab TEMP with either a single sensor per channel or two sensors per channel pair.
Four-wire, single-sensor
A four-wire, single-sensor connected to the first channel of a channel pair is shown in Figure 7.
18
Sensor Connections
I#+
NC
C#H
C#L
4W##
IC##
C#H
C#L
GND
I#-
RedLab TEMP User's Guide
Figure 7. Four-wire, single RTD or thermistor sensor measurement configuration
I#+
NC
C#H
C#L
4W##
IC##
C#H
C#L
GND
I#-
A four-wire, single-sensor connected to the second channel of a channel pair is shown in Figure 8.
Figure 8. Four-wire, single RTD or thermistor sensor measurement configuration
C#H
C#L
GND
I#-
I#+
NC
C#H
C#L
4W##
A four-wire, two-sensor measurement configuration is shown in Figure 9.
Figure 9. Four-wire, two RTD or thermistor sensors measurement configuration
When configured for four-wire, two sensor mode, both sensors must be connected to obtain proper
measurements.
19
RedLab TEMP User's Guide
Sensor Connections
Semiconductor sensor measurements
Semiconductor sensors are suitable over a range of approximately -40 °C to 125 °C, where an accuracy of ±2
°C is adequate. The temperature measurement range of a semiconductor sensor is small when compared to
thermocouples and RTDs. However, semiconductor sensors can be accurate, inexpensive and easy to interface
with other electronics for display and control.
The RedLab TEMP makes high-resolution measurements of semiconductor sensors, such as the LM36 or
equivalent, and returns a 32-bit floating point value in either a voltage or temperature format.
Use InstaCal to select the sensor type (TMP36 or equivalent) and the sensor input channel to connect the
sensor.
Wiring configuration
TMP36
I#+
NC
C#H
C#L
4W##
IC##
C#H
C#L
GND
I#-
5V
You can connect a TMP36 (or equivalent) semiconductor sensor to the RedLab TEMP using a single-ended
configuration, as shown in Figure 10. The RedLab TEMP also provides +5V and GND pins for powering the
sensor.
Figure 10. Semiconductor sensor measurement configuration
The software outputs the measurement data as a 32-bit floating point value in either voltage or temperature.
20
RedLab TEMP User's Guide
Sensor Connections
Digital I/O connections
You can connect up to eight digital I/O lines to the screw terminals labeled DIO0 to DIO7. You can configure
each digital bit for either input or output. All digital I/O lines are pulled up to +5V with a 47 K ohm resistor
(default). You can request the factory to configure the resistor for pull-down to ground if desired.
When you configure the digital bits for input, you can use the RedLab TEMP digital I/O terminals to detect the
state of any TTL-level input. Refer to the schematic shown in Figure 11. If you set the switch to the +5V input,
DIO0 reads TRUE (1). If you move the switch to GND, DIO0 reads FALSE (0).
DIO0
+GND
+5V
Figure 11. Schematic showing switch detection by digital channel DIO0
Caution! All ground pins on the RedLab TEMP (pins 9, 19, 28, 38) are common and are isolated from earth
ground. If a connection is made to earth ground when using digital I/O and conductive thermocouples, the
thermocouples are no longer isolated. In this case, thermocouples must not be connected to any conductive
surfaces that may be referenced to earth ground.
For general information regarding digital signal connections and digital I/O techniques, refer to the Guide to
Signal Connections (available on our RedLab CD under „ICalUL\Documents“).
21
Chapter 4
Functional Details
Thermocouple measurements
A thermocouple consists of two dissimilar metals that are joined together at one end. When the junction of the
metals is heated or cooled, a voltage is produced that correlates to temperature.
The RedLab TEMP hardware level-shifts the thermocouple’s output voltage into the A/D’s common mode input
range by applying +2.5 V to the thermocouple’s low side at the C#L input. Always connect thermocouple
sensors to the RedLab TEMP in a floating fashion. Do not attempt to connect the thermocouple low side C#L to
GND or to a ground referencing resistor.
Cold junction compensation (CJC)
When you connect the thermocouple sensor leads to the sensor input channel, the dissimilar metals at the
RedLab TEMP terminal blocks produce an additional thermocouple junction. This junction creates a small
voltage error term which must be removed from the overall sensor measurement using a cold junction
compensation technique. The measured voltage includes both the thermocouple voltage and the cold junction
voltage. To compensate for the additional cold junction voltage, the RedLab TEMP subtracts the cold junction
voltage from the thermocouple voltage.
The RedLab TEMP has two high-resolution temperature sensors that are integrated into the design of the
RedLab TEMP. One sensor is located on the right side of the package, and one sensor is located at the left side.
The CJC sensors measure the average temperature at the terminal blocks so that the cold junction voltage can be
calculated. A software algorithm automatically corrects for the additional thermocouples created at the terminal
blocks by subtracting the calculated cold junction voltage from the analog input's thermocouple voltage
measurement.
Increasing the thermocouple length
If you need to increase the length of your thermocouple, use the same type of thermocouple wires to minimize
the error introduced by thermal EMFs.
Data linearization
After the CJC correction is performed on the measurement data, an on-board microcontroller automatically
linearizes the thermocouple measurement data using National Institute of Standards and Technology (NIST)
linearization coefficients for the selected thermocouple type.
The measurement data is then output as a 32-bit floating point value in the configured format (voltage or
temperature).
Open-thermocouple detection (OTD)
The RedLab TEMP is equipped with an open-thermocouple detection for each analog input channel. With
OTD, any open-circuit or short-circuit condition at the thermocouple sensor is detected by the software. An
open channel is detected by driving the input voltage to a negative value outside the range of any thermocouple
output. The software recognizes this as an invalid reading and flags the appropriate channel. The software
continues to sample all channels when OTD is detected.
Input leakage current
With open-thermocouple detection enabled, 105 nA (max.) of input leakage current is injected into the
thermocouple. This current can cause an error voltage to develop across the lead resistance of the thermocouple
that is indistinguishable from the thermocouple voltage you are measuring. You can estimate this error voltage
with the following formula:
error voltage = resistance of the thermocouple x 105 nA
22
RedLab TEMP User's Guide
Functional Details
To reduce the error, reduce the length of the thermocouple to lower its resistance, or lower the AWG of the wire
by using a wire with a larger diameter. With open-thermocouple detection disabled, 30 nA (max) of input
leakage current is injected into the thermocouple.
RTD and thermistor measurements
RTDs and thermistors are resistive devices that require an excitation current to produce a voltage drop that can
be measured differentially across the sensor. The RedLab TEMP measures the sensor resistance by forcing a
known excitation current through the sensor and then measuring (differentially) the voltage across the sensor to
determine its resistance.
After the voltage measurement is made, the resistance of the RTD is calculated using Ohms law – the sensor
resistance is calculated by dividing the measured voltage by the current excitation level (±Ix) source. The value
of the ±Ix source is stored in local memory.
Once the resistance value is calculated, the value is linearized in order to convert it to a temperature value. The
measurement is returned by software as a 32-bit floating point value in a voltage, resistance or temperature
format.
Data linearization
An on-board microcontroller automatically performs linearization on RTD and thermistor measurements.
ƒ
ƒ
RTD measurements are linearized using a Callendar-Van Dusen coefficients algorithm (you select DIN,
SAMA, or ITS-90).
Thermistor measurements are linearized using a Steinhart-Hart linearization algorithm (you supply the
coefficients from the sensor manufacturer's data sheet).
USB connector
The USB connector provides +5V power and communication. No external power supply is required.
LED
The LED indicates the communication status of the RedLab TEMP. It uses up to 5 mA of current. The table
below defines the function of the RedLab TEMP LED.
LED Illumination
LED
Illumination
Indication
Steady green
Pulsing green
The RedLab TEMP is connected to a computer or external USB hub.
Data is being transferred.
Upon connection, the LED should flash three times and then remain lit (indicates a successful
installation).
23
RedLab TEMP User's Guide
Functional Details
Power
The two +5V terminals are isolated (500VDC) from the USB +5V.
Caution! Each +5V terminal is an output. Do not connect to an external power supply or you may damage
the RedLab TEMP and possibly the computer.
24
Chapter 5
Specifications
Typical for 25 °C unless otherwise specified.
Specifications in italic text are guaranteed by design.
Analog input
Table 1. Generic analog input specifications
Parameter
Conditions
Specification
A/D converters
Number of channels
Input isolation
Four dual 24-bit, Sigma-Delta type
8 differential
500 VDC minimum between field wiring and
USB interface
Software programmable to match sensor type
Channel configuration
Differential input voltage range
for the various sensor categories
Absolute maximum input voltage
Input impedance
Input leakage current
Normal mode rejection ratio
Common mode rejection ratio
Resolution
No missing codes
Input coupling
Warm-up time
Open thermocouple detect
CJC sensor accuracy
Thermocouple
±0.080 V
RTD
Thermistor
Semiconductor sensor
±C0x through ±C7x relative to
GND (pins 9, 19, 28, 38)
0 to 0.5 V
0 to 2 V
0 to 2.5 V
±25 V power on, ±40 V power off.
Open thermocouple detect
disabled
Open thermocouple detect
enabled
fIN = 60 Hz
fIN = 50 Hz/60 Hz
15 °C to 35 °C
0 °C to 70 °C
25
5 Gigohm, min.
30 nA max.
105 nA max.
90 dB min.
100 dB min.
24 bits
24 bits
DC
30 minutes min.
Automatically enabled when the channel pair is
configured for thermocouple sensor.
The maximum open detection time is 3 seconds.
±0.25 °C typ.,±0.5 °C max.
–1.0 to +0.5 °C max
RedLab TEMP User's Guide
Specifications
Channel configurations
Table 2. Channel configuration specifications
Sensor Category
Disabled
Thermocouple
Semiconductor sensor
RTD and thermistor
Conditions
Specification
2-wire input configuration with a single sensor
2-wire input configuration with two sensors
3-wire configuration with a single sensor per channel pair
4-wire input configuration with a single sensor
4-wire input configuration with two sensors
8 differential channels
8 differential channels
4 differential channels
8 differential channels
4 differential channels
2 differential channels
4 differential channels
Note 1: Internally, the RedLab TEMP has four, dual-channel, fully differential A/Ds providing a total of eight
differential channels. The analog input channels are therefore configured in four channel pairs with
CH0/CH1 sensor inputs, CH2/CH3 sensor inputs, CH4/CH5 sensor inputs, and CH6/CH7 sensor
inputs paired together. This "channel-pairing" requires the analog input channel pairs be configured to
monitor the same category of temperature sensor. Mixing different sensor types of the same category
(such as a type J thermocouple on channel 0 and a type T thermocouple on channel 1) is valid.
Note 2: Channel configuration information is stored in the EEPROM of the isolated microcontroller by the
firmware whenever any item is modified. Modification is performed by commands issued over USB
from an external application, and the configuration is made non-volatile through the use of the
EEPROM.
Note 3: The factory default configuration is Disabled. The Disabled mode will disconnect the analog inputs
from the terminal blocks and internally ground all of the A/D inputs. This mode also disables each of
the current excitation sources.
Compatible sensors
Table 3. Compatible sensor type specifications
Parameter
Conditions
Thermocouple
J: -210 °C to 1200 °C
K: -270 °C to 1372 °C
R: -50 °C to 1768 °C
S: -50 °C to 1768 °C
T: -270 °C to 400 °C
N: -270 °C to 1300 °C
E: -270 °C to 1000 °C
B: 0 °C to 1820 °C
100 ohm PT (DIN 43760: 0.00385 ohms/ohm/°C)
100 ohm PT (SAMA: 0.003911 ohms/ohm/°C)
100 ohm PT (ITS-90/IEC751:0.0038505 ohms/ohm/°C)
Standard 2,252 ohm through 30,000 ohm
TMP36 or equivalent
RTD
Thermistor
Semiconductor / IC
26
RedLab TEMP User's Guide
Specifications
Accuracy
Thermocouple measurement accuracy
Table 4. Thermocouple accuracy specifications, including CJC measurement error
Sensor Type
Maximum error
Typical error
Temperature range
J
±1.499 °C
±0.643 °C
±1.761 °C
±0.691 °C
±2.491°C
±1.841 °C
±2.653 °C
±1.070 °C
±1.779 °C
±0.912 °C
±1.471 °C
±0.639 °C
±1.717 °C
±0.713 °C
±1.969 °C
±0.769 °C
±0.507 °C
±0.312 °C
±0.538 °C
±0.345 °C
±0.648 °C
±0.399 °C
±0.650 °C
±0.358 °C
±0.581 °C
±0.369 °C
±0.462 °C
±0.245 °C
±0.514 °C
±0.256 °C
±0.502 °C
±0.272 °C
-210 to 0 °C
0 to 1200 °C
-210 to 0 °C
0 to 1372 °C
-50 to 250 °C
250 to 1768.1 °C
-50 to 250 °C
250 to 1768.1 °C
250 to 700 °C
700 to 1820 °C
-200 to 0 °C
0 to 1000 °C
-200 to 0 °C
0 to 600 °C
-200 to 0 °C
0 to 1300 °C
K
S
R
B
E
T
N
Note 4: Thermocouple measurement accuracy specifications include linearization, cold-junction compensation
and system noise. These specs are for one year, or 3000 operating hours, whichever comes first, and
for operation of the RedLab TEMP between 15 °C and 35 °C. For measurements outside this range,
add ±0.5 degree to the maximum error shown. There are CJC sensors on each side of the module. The
accuracy listed above assumes the screw terminals are at the same temperature as the CJC sensor.
Errors shown do not include inherent thermocouple error. Please contact your thermocouple supplier
for details on the actual thermocouple error.
Note 5: Thermocouples must be connected to the RedLab TEMP such that they are floating with respect to
GND (pins 9, 19, 28, 38). The RedLab TEMP GND pins are isolated from earth ground, so connecting
thermocouple sensors to voltages referenced to earth ground is permissible as long as the isolation
between the GND pins and earth ground is maintained.
Note 6: When thermocouples are attached to conductive surfaces, the voltage differential between multiple
thermocouples must remain within ±1.4 V. For best results we recommend the use of insulated or
ungrounded thermocouples when possible.
27
RedLab TEMP User's Guide
Specifications
Semiconductor sensor measurement accuracy
Table 5. Semiconductor sensor accuracy specifications
Sensor Type
Temperature Range (°C)
Maximum Accuracy Error
TMP36 or equivalent
-40 to 150 °C
±0.50 °C
Note 7: Error shown does not include errors of the sensor itself. These specs are for one year while operation
of the RedLab TEMP unit is between 15 °C and 35 °C. Please contact your sensor supplier for details
on the actual sensor error limitations.
RTD measurement accuracy
Table 6. RTD measurement accuracy specifications
RTD
Sensor
Temperature
Maximum Accuracy Error (°C)
Ix+ = 210 µA
Typical Accuracy Error (°C)
Ix+ = 210 µA
PT100, DIN, US or
ITS-90
-200°C to -150°C
-150°C to -100°C
-100°C to 0°C
0°C to 100°C
100°C to 300°C
300°C to 600°C
±2.85
±1.24
±0.58
±0.38
±0.39
±0.40
±2.59
±0.97
±0.31
±0.11
±0.12
±0.12
Note 8: Error shown does not include errors of the sensor itself. The sensor linearization is performed using a
Callendar-Van Dusen linearization algorithm. These specs are for one year while operation of the
RedLab TEMP unit is between 15 °C and 35 °C. The specification does not include lead resistance
errors for 2-wire RTD connections. Please contact your sensor supplier for details on the actual sensor
error limitations.
Note 9: Resistance values greater than 660 ohms cannot be measured by the RedLab TEMP in the RTD mode.
The 660 ohm resistance limit includes the total resistance across the current excitation (±Ix) pins,
which is the sum of the RTD resistance and the lead resistances.
Note 10:
For accurate three wire compensation, the individual lead resistances connected to the ±Ix pins
must be of equal value.
Thermistor measurement accuracy
Table 7. Thermistor measurement accuracy specifications
Thermistor
Temperature Range
Maximum Accuracy Error (°C)
Ix+ = 10 µA
2252 Ω
3000 Ω
5000 Ω
10000 Ω
30000 Ω
-40 to120 °C
-40 to120 °C
-35 to120 °C
-25 to120 °C
-10 to120 °C
±0.05
±0.05
±0.05
±0.05
±0.05
Note 11:
Error shown does not include errors of the sensor itself. The sensor linearization is performed
using a Steinhart-Hart linearization algorithm. These specs are for one year while operation of the
RedLab TEMP unit is between 15 °C and 35 °C. The specification does not include lead resistance
errors for 2-wire thermistor connections. Please contact your sensor supplier for details on the actual
sensor error limitations. Total thermistor resistance on any given channel pair must not exceed 180 k
ohms. Typical resistance values at various temperatures for supported thermistors are shown in Table
8.
28
RedLab TEMP User's Guide
Specifications
Table 8. Typical thermistor resistance specifications
Temp
2252 Ω
thermistor
3000 Ω
thermistor
5 kΩ
thermistor
10 kΩ
thermistor
30 kΩ
thermistor
-40 °C
-35 °C
-30 °C
-25 °C
-20 °C
-15 °C
-10 °C
-5 °C
0 °C
76 kΩ
55 kΩ
40 kΩ
29 kΩ
22 kΩ
16 kΩ
12 kΩ
9.5 kΩ
7.4 kΩ
101 kΩ
73 kΩ
53 kΩ
39 kΩ
29 kΩ
22 kΩ
17 kΩ
13 kΩ
9.8 kΩ
168 kΩ
121 kΩ
88 kΩ
65 kΩ
49 kΩ
36 kΩ
28 kΩ
21 kΩ
16 kΩ
240 kΩ (Note 12)
179 kΩ
135 kΩ
103 kΩ
79 kΩ
61 kΩ
48 kΩ
37 kΩ
29 kΩ
885 kΩ (Note 12)
649 kΩ (Note 12)
481 kΩ (Note 12)
360 kΩ (Note 12)
271 kΩ (Note 12)
206 kΩ (Note 12)
158 kΩ
122 kΩ
95 kΩ
Resistance values greater than 180 k ohms cannot be measured by the RedLab TEMP in the
thermistor mode. The 180 k ohm resistance limit includes the total resistance across the current
excitation (±Ix) pins, which is the sum of the thermistor resistance and the lead resistances.
Note 13:
For accurate three wire compensation, the individual lead resistances connected to the ±Ix pins
must be of equal value.
Note 12:
Throughput rate
Table 9. Throughput rate specifications
Number of Input Channels
Maximum Throughput
1
2
3
4
5
6
7
8
2 Samples/second
2 S/s on each channel, 4 S/s total
2 S/s on each channel, 6 S/s total
2 S/s on each channel, 8 S/s total
2 S/s on each channel, 10 S/s total
2 S/s on each channel, 12 S/s total
2 S/s on each channel, 14 S/s total
2 S/s on each channel, 16 S/s total
Note 14:
The analog inputs are configured to run continuously. Each channel is sampled twice per second.
The maximum latency between when a sample is acquired and the temperature data is provided by the
USB unit is approximately 0.5 seconds.
29
RedLab TEMP User's Guide
Specifications
Digital input/output
Table 10. Digital input/output specifications
Digital type
Number of I/O
Configuration
Pull-up/pull-down configuration
Digital I/O transfer rate (software paced)
Input high voltage
Input low voltage
Output low voltage (IOL = 2.5 mA)
Output high voltage (IOH = –2.5 mA)
Note 15:
CMOS
8 (DIO0 through DIO7)
Independently configured for input or output.
Power on reset is input mode.
All pins pulled up to +5 V via 47 K resistors (default). Pull-down to ground
(GND) also available.
1. Digital input – 50 port reads or single bit reads per second typ.
2. Digital output – 100 port writes or single bit writes per second typ.
2.0 V min., 5.5 V absolute max.
0.8 V max., –0.5 V absolute min.
0.7 V max.
3.8 V min.
All ground pins on the RedLab TEMP (pins 9, 19, 28, 38) are common and are isolated from earth
ground. If a connection is made to earth ground when using digital I/O and conductive thermocouples,
the thermocouples are no longer isolated. In this case, thermocouples must not be connected to any
conductive surfaces that may be referenced to earth ground.
Memory
Table 11. Memory specifications
EEPROM
1,024 bytes isolated micro reserved for sensor configuration
256 bytes USB micro for external application use
Microcontroller
Table 12. Microcontroller specifications
Type
Two high-performance 8-bit RISC microcontrollers
USB +5V voltage
Table 13. USB +5V voltage specifications
Parameter
Conditions
Specification
USB +5V (VBUS) input voltage range
4.75 V min. to 5.25 V max.
30
RedLab TEMP User's Guide
Specifications
Power
Table 14. Power specifications
Parameter
Conditions
Specification
Supply current
Supply current
(Note 16)
User +5V output voltage range
(terminal block pin 21 and pin 47)
User +5V output current
(terminal block pin 21 and pin 47)
Isolation
USB enumeration
Continuous mode
<100 mA
140 mA typ.
Connected to self-powered hub. (Note 17)
Bus-powered and connected to a self-powered hub. (Note 17)
4.75 V min. to
5.25 V max.
10 mA max.
Measurement system to PC
500 VDC min.
This is the total current requirement for the RedLab TEMP which includes up to 10 mA for the
status LED.
Note 17:
Self-Powered Hub refers to a USB hub with an external power supply. Self-powered hubs allow a
connected USB device to draw up to 500 mA.
Note 16:
Root Port Hubs reside in the PC’s USB Host Controller. The USB port(s) on your PC are root port
hubs. All externally powered root port hubs (desktop PC’s) provide up to 500 mA of current for a USB
device. Battery-powered root port hubs provide 100 mA or 500 mA, depending upon the manufacturer.
A laptop PC that is not connected to an external power adapter is an example of a battery-powered root
port hub.
USB specifications
Table 15. USB specifications
USB device type
Device compatibility
USB cable type
USB cable length
USB 2.0 (full-speed)
USB 1.1, USB 2.0
Self-powered, 100 mA consumption max
A-B cable, UL type AWM 2527 or equivalent. (min 24 AWG VBUS/GND,
min 28 AWG D+/D–)
3 meters max.
31
RedLab TEMP User's Guide
Specifications
Current excitation outputs (Ix+)
Table 16. Current excitation output specifications
Parameter
Conditions
Specification
Configuration
Current excitation output ranges
4 dedicated pairs:
±I1 - CH0/CH1
±I2 - CH2/CH3
±I3 - CH4/CH5
±I4 - CH6/CH7
10 µA typ.
210 µA typ.
±5% typ.
200 ppm/°C
2.1 ppm/V max.
0.3 ppm/V typ.
3.90 V max.
-0.03 V min.
Thermistor
RTD
Tolerance
Drift
Line regulation
Load regulation
Output compliance voltage
(relative to GND pins 9, 19, 28, 38)
The RedLab TEMP has four current excitation outputs, with ±I1 dedicated to the CH0/CH1 analog
inputs, ±I2 dedicated to CH2/CH3, ±I3 dedicated to CH4/CH5, and ±I4 dedicated to CH6/CH7. The
excitation output currents should always be used in this dedicated configuration.
Note 19:
The current excitation outputs are automatically configured based on the sensor (thermistor or
RTD) selected.
Note 18:
Environmental
Table 17. Environmental specifications
Operating temperature range
Storage temperature range
Humidity
0 to 70 ° C
-40 to 85 ° C
0 to 90% non-condensing
Mechanical
Table 18. Mechanical specifications
Dimensions
User connection length
127 mm (L) x 88.9 mm (W) x 35.56 (H)
3 meters max.
Screw terminal connector type and pin out
Table 19. Screw terminal connector specifications
Connector type
Wire gauge range
Screw terminal
16 AWG to 30 AWG
32
RedLab TEMP User's Guide
Specifications
Screw terminal pin out
Table 20. Screw terminal pin out
Pin
Signal Name
1
I1+
2
NC
Pin Description
Pin
CH0/CH1 current excitation source
Signal Name
27
I4-
28
GND
Pin Description
CH6/CH7 current excitation return
3
C0H
CH0 sensor input (+)
29
C7L
CH7 sensor input (-)
4
C0L
CH0 sensor input (-)
30
C7H
CH7 sensor input (+)
5
4W01
CH0/CH1 4-wire, 2 sensor common
31
IC67
CH6/CH7 2 sensor common
6
IC01
CH0/CH1 2-sensor common
32
4W67
CH6/CH7 4-wire, 2 sensor common
7
C1H
CH1 sensor input (+)
33
C6L
CH6 sensor input (-)
8
C1L
CH1 sensor input (-)
34
C6H
CH6 sensor input (+)
9
GND
35
NC
10
I1-
36
I4+
CH0/CH1 current excitation return
CJC sensor
11
I2+
12
NC
13
C2H
14
15
CH6/CH7 current excitation source
CJC sensor
CH2/CH3 current excitation source
37
I3-
38
GND
CH4/CH5 current excitation return
CH2 sensor input (+)
39
C5L
C2L
CH2 sensor input (-)
40
C5H
CH5 sensor input (+)
4W23
CH2/CH3 4-wire, 2 sensor common
41
IC45
CH4/CH5 2 sensor common
CH5 sensor input (-)
16
IC23
CH2/CH3 2 sensor common
42
4W45
CH4/CH5 4-wire, 2 sensor common
17
C3H
CH3 sensor input (+)
43
C4L
CH4 sensor input (-)
18
C3L
CH3 sensor input (-)
44
C4H
CH4 sensor input (+)
19
GND
45
NC
20
I2-
CH2/CH3 current excitation return
46
I3+
CH4/CH5 current excitation source
21
+5V
+5V output
47
+5V
+5V output
22
GND
48
GND
23
DIO0
Digital Input/Output
49
DIO7
Digital Input/Output
24
DIO1
Digital Input/Output
50
DIO6
Digital Input/Output
25
DIO2
Digital Input/Output
51
DIO5
Digital Input/Output
26
DIO3
Digital Input/Output
52
DIO4
Digital Input/Output
33
Meilhaus Electronic GmbH
Am Sonnenlicht 2
D-82239 Alling, Germany
Phone: +49 (0)8141 - 5271-0
Fax: +49 (0)8141 - 5271-129
E-Mail: sales@meilhaus.com
http://www.meilhaus.com
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