Table Of Contents - Eltek Data Loggers

Table Of Contents - Eltek Data Loggers
Table Of Contents
1.
Overview of the operating buttons ......................................... 4
2.
The functions of the datalogger .............................................. 5
2.1 LOG .................................................................................. 5
2.2 METER ............................................................................. 5
2.3 REVIEW ............................................................................ 5
2.4 TIME / date ....................................................................... 5
2.5 START time / date ............................................................. 5
2.6 INT log / sample (logging/sampling interval) ...................... 5
2.7 OUTPUT ........................................................................... 6
2.8 MODE ............................................................................... 6
2.9 CHANNEL SETUP ............................................................ 6
2.10 STAT (status).................................................................... 6
3.
How to start logging from the default settings ...................... 7
3.1 Set time/date ..................................................................... 7
3.2 Select logging interval ....................................................... 8
3.3 Set the type of logging required ......................................... 8
3.4 Set the number and types of channels ............................... 9
3.5 Start logging .................................................................... 11
3.6 Stop logging .................................................................... 12
4.
More about the functions of the datalogger ..........................13
4.1 The LOG f unction ............................................................ 13
4.2 The METER function ....................................................... 15
4.3 The REVIEW function ..................................................... 16
4.4 The TIME and date function ............................................ 17
4.5 The delayed START function........................................... 18
4.6 The INT function (logging/sampling interval).................... 19
4.7 The OUTPUT function ..................................................... 20
4.8 The MODE function ......................................................... 21
4.9 The CHANNEL SETUP function ...................................... 27
4.10 The STAT function ........................................................... 31
5.
Making connections to the datalog ger ..................................35
5.1 Wiring up thermistor sensors ........................................... 35
5.2 Wiring up platinum resistance sensors............................. 35
5.3 Wiring up sensors to voltage channels............................. 36
5.4 Wiring up sensors to current channels ............................. 37
1
5.5
5.6
5.7
5.8
5.9
5.10
How to provide a power supply to the sensors ................. 38
Wiring Up Current Loop Sensors driven by the Squirrel ... 39
Wiring up an AC voltage input ......................................... 39
Wiring up a pulse count channel ...................................... 40
Wiring up event channels ................................................ 41
Wiring up for external triggers ......................................... 42
6.
Troubleshooting guide ...........................................................43
6.1 “Why won’t it do that?” ..................................................... 43
7.
Memory Card Squirrels ...........................................................44
7.1 Types Of Card ................................................................. 44
7.2 Preparing the Card .......................................................... 44
7.3 Squirrel Settings .............................................................. 45
7.4 Extracting the data .......................................................... 48
8.
Electricity Squirrels (1010, 1020) ............................................49
8.1 Logger functions .............................................................. 49
8.2 Selecting ranges .............................................................. 49
8.3 Making connections to the datalogger .............................. 50
9.
Squirrels with pH channels ....................................................51
9.1 Channel Selection ........................................................... 51
9.2 Pre-setting the Temperature ............................................ 51
9.3 Choosing the Calibration Point ........................................ 52
9.4 Calibrating the Midpoint (pH7.0) ...................................... 52
9.5 Calibrating the Slope ....................................................... 53
9.6 Current Consumption and Battery Life ............................. 54
9.7 Care and Use of pH Probes ............................................. 54
10.
Special Instructions ................................................................55
10.1 Alarms............................................................................ 55
10.2 Wind Speed & Direction ................................................. 56
11.
Modems ...................................................................................58
12.
Model 401/451 and derivatives ...............................................60
13.
Fast Logging ...........................................................................61
13.1 Logging Interv al ............................................................. 61
13.2 Translation with Darca .................................................... 61
13.3 Darca Contact ................................................................ 62
2
14.
GenII Radio Data Logging System .........................................63
14.1 Introduction .................................................................... 63
14.2 Initial Setup .................................................................... 63
14.3 System Configuration ..................................................... 65
15.
Darca ........................................................................................79
15.1 Introduction .................................................................... 79
15.2 Overview........................................................................ 80
15.3 The Main W indow .......................................................... 81
15.4 The Contact Wizard ....................................................... 82
15.5 The Contact Window ...................................................... 82
15.6 The Status Bar ............................................................... 83
15.7 Menus ............................................................................ 83
15.8 The Graph Window ........................................................ 87
15.9 Automated Contact with a Squirrel ................................. 89
16.
Safety and operating conditions ............................................90
16.1 Operator safety .............................................................. 90
16.2 Squirrel safety ................................................................ 90
16.3 Errors caused by ground connections ............................. 90
16.4 Operating conditions ...................................................... 90
16.5 Protection against memory loss...................................... 91
16.6 Changing batteries ......................................................... 91
16.7 Resetting the datalogger................................................. 91
16.8 Changing fuses .............................................................. 92
16.9 Sensor supply voltage .................................................... 92
17.
Technical data .........................................................................94
17.1 Inputs, ranges and resolutions ........................................ 94
17.2 Specification ................................................................... 95
18.
Connections ............................................................................96
18.1 Signal connector ............................................................ 96
18.2 Output connector ............................................................ 96
19.
Communications leads RX250AL and SC250 ........................98
Declaration of Conformity .............................................................. 100
Manufacturer ........................................................................... 100
Description of Equipment ........................................................ 100
Applied Standards ................................................................... 100
3
1. Overview of the operating buttons
The operating buttons allow the setup of all of the major functions of the
logger.
function selects the function.
select selects the channel or
sub function.
set is used to change any of
the settings.
function select
set
To switch the datalogger on, press and hold function. To switch it off,
leave in LOG or OUTPUT function for a few seconds. If the datalogger
is left on in any other function, it will automatically switch off after 4
minutes.
4
2. The functions of the datalogger
2.1 LOG
Used to start and stop logging. In addition, this function displays the
number of readings already stored in the memory (used), and the
number of readings that may be stored in the remaining memory (free).
All the readings stored in memory may be erased in this function. In
addition, this function will allow you to display how many separate runs
have been recorded.
2.2 METER
Displays the value of the channels that have been selected, in the
appropriate units. The readings are updated every second.
2.3 REVIEW
Displays the recorded values of the selected channels, starting with the
first reading in the last run (if the logger is not currently logging). If the
logger is currently logging, then the first reading in the current run is
displayed.
2.4 TIME / date
Displays the real time and date on two lines. The 24 hour clock may be
displayed in the appropriate country format (see 2.10f); the time
increments every second.
2.5 START time / date
This option allows you to set a future time and date at which logging will
start.
2.6 INT log / sample (logging/sampling interval)
The interval function is used to set the time intervals at which readings
are taken and stored in memory. The logging interval can be set
between 1 second and 24 hours in 1-second increments. The second
line is used to set the time intervals at which inputs are sampled; these
readings are averaged and then stored in memory at the logging
interval.
5
2.7 OUTPUT
Used for output of recorded data to a computer. During downloading of
data, the LCD displays the number of blocks to be downloaded and this
is decremented after each successful transmission of a block. No baud
rate setting is required as it is automatically selected.
2.8 MODE
Used to select the type of logging required, namely Interval, Average,
Event, Event+Interval, Event+Average. This function allows you to
select how logging may be started and stopped via an external trigger, if
required. In addition, you can select whether you wish logging to stop
when the memory is full or whether logging continues and old data is
overwritten.
2.9 CHANNEL SETUP
Used to select the channels from which you require data to be recorded.
The range for each channel is also selected, which could include
engineering units if these have been set up by Darca. This function also
displays how many channels have been selected to record.
2.10 STAT (status)
This function displays the following status information concerning the
datalogger: a)
b)
c)
d)
e)
f)
g)
h)
i)
j)
k)
internal battery voltage
number of days remaining of viable battery life when logging
external supply voltage
memory size (with the ability to change memory size in 1K
increments)
sensor power-on time (up to 60 seconds before the reading is taken)
date format configuration (adjustable)
language format (adjustable)
mains frequency filter (adjustable)
model number and current version of firmware
temperature units
network option
6
3. How to start logging from the default settings
3.1 Set time/date
The real time and date are displayed on two lines. The time is set in the
format HH:MM:SS. and the date default format is DD/MM/YY. Press
function until the display shows: T I ME
d a t e
1 0 : 4 2 : 5 9
2 5 / 1 2 / 9 4
Press set and the following prompt appears: T I ME
HO L D
T O
1 0 : 4 3 : 1 1
C H A N G E
Hold set button and cursor will appear: - (the clock will stop)
T I ME
d a t e
1 0 : 4 3 : 1 7
2 5 / 1 2 / 9 4
Press select to move cursor: T I ME
d a t e
1 0 : 4 3 : 1 7
2 5 / 1 3 / 9 4
Press set to change value: T I ME
d a t e
1 0 : 4 6 : 1 7
2 5 / 1 2 / 9 4
Press function when settings are correct: - (cursor will disappear and
clock will restart with new settings).
T I ME
1 0 : 4 6 : 1 9
d a t e
2 5 / 1 2 / 9 4
If invalid data is entered, the display changes the settings to the nearest
valid time/date.
7
3.2 Select logging interval
The logging interval can be set between 1 second and 24 hours in 1second increments. Recordings are stored at this interval. Press
function until display shows: I N T
l o g
s a m p l e
0 0 : 0 0 : 3 0
0 0 : 0 0 : 0 0
Press set to display: I N T
l o g
HO L D T O
0 0 : 0 0 : 3 0
C H A N G E
Hold set button and cursor will appear: I N T
l o g
s a m p l e
0 0 : 0 0 : 3 0
0 0 : 0 0 : 0 0
Press select to move cursor: I N T
l o g
s a m p l e
0 0 : 0 0 : 3 0
0 0 : 0 0 : 0 0
Press set to change value: I N T
l o g
s a m p l e
0 0 : 0 0 : 3 5
0 0 : 0 0 : 0 0
This example changes the logging interval from 30 to 35 seconds. Press
function to clear the cursor and to continue with setup.
3.3 Set the type of logging required
The possible types of logging are detailed in section 4.8.1. However, the
default setting is for recording data at fixed intervals only. Press
function until mode is displayed: M O D E
l o g
8
i n t e r v a l
You need do nothing else except set which channels to log if you simply
need to record data at the logging intervals set in section 3.2.
3.4 Set the number and types of channels
Each model has a specified combination of channels, please consult the
data sheet in Section 17 for details of your particular model. This
section will guide you to set up a temperature and voltage/current
channel. Press function until the following is displayed: C H A N N E L
1
u s e d
S E T U P
The default setting will always be the first range of the first channel. If
you deselect all channels, then you will not be able to progress until you
have configured at least one channel. In this case, pressing the function
key will only display the following message: C H A N N E L
S E T U P
NON E S E L E C T E D
Please proceed to the following sections for instructions on how to set
up specific channels.
3.4.1 Temperature chann el setup
Thermistors, thermocouples and platinum resistance sensors are
capable of accurately measuring temperatures within different ranges.
Grant Squirrel dataloggers offer the appropriate ranges for each type of
sensor. This example is for a datalogger with thermistor type inputs.
Press select once and the following message will be displayed: (Pressing select several times will allow you to scroll through the
channels)
C H
1
- 3 0 . 0
° C
/
9
7 0 . 0
Press set and hold for 3 seconds: C H 1
HO L D
C H
T O
1
- 5 0 . 0
° C
C H A N G E
° C
/
1 5 0 . 0
The temperature range then increments to the next available range with
every press of the set button: C H
1
- 2 2 . 0
° F
/
1 5 8 . 0
Leave the display showing your chosen range and press select to set up
another channel.
3.4.2 Voltage/current channel setup
These channels may be configured for voltage or current. There are 18
voltage ranges and 2 current ranges. Voltage/current channels have an
additional range called the EU (Engineering Units) range where the user
can select specific engineering units (e.g. m/s) and a max/min scale
(e.g. 0/50 m/s). The appropriate voltage/current range is then selected
from the existing hardware ranges (e.g. 0/1 V). In the above example,
0/50 m/s = 0/1V and the display in METER mode will show readings in
m/s. All data in this channel will be stored and downloaded using m/s as
the unit. In the above example, the CHANNEL SETUP function will
alternate between the following displays: C H
C H
6
E U m / s
0 . 0
/
5 0 . 0
6
E U V
0 . 0 0 0
/
1 . 0 0 0
The EU range may only be set up using Darca (please see price list or
contact your distributor for details). Whenever a voltage/current channel
has not been set up, the initial range is always the default EU range and
10
is displayed as follows: C H
C H
6
E U %
0 . 0
/
1 0 0 . 0
6
E U V
0 . 0 0 0
/
1 . 0 0 0
Press select to change channel. For example, select channel 5: C H
5
n o t
u s e d
Press set and hold for 3 seconds: C H 5
HO L D
T O
C H A N G E
Now press set to scroll through the voltage/current ranges. Leave the
display showing your chosen range and press select to set up another
channel or press function to continue with logger setup.
3.4.3 Humidity channel setup
The default EU (Engineering Unit) range for all voltage/current inputs
(as described in 4.4.2), is 0/1V = 0/100% and is suitable for Grant
humidity probes. These probes plug into any voltage/current input
selected using the CHANNEL SETUP function. Press and hold set for 3
seconds to change an unused voltage/current channel to the default EU
range. N.B. It is essential that the ‘sensor on’ time is set to 1
second or greater. Please see 4.10.4 for further details.
3.5 Start logging
Press function until the following is displayed: L OG
u s e d
o f f
0
Now press and hold set to start logging: -
11
L OG
HO L D
o f f
T O S T A R T
The display shows that logging has started and will turn off within 10
seconds to conserve power. (Some memory slots will be used up
immediately in order to store the header file.)
L OG
u s e d
o n
1 4
3.6 Stop logg ing
Press function to wake up the logger: L OG
u s e d
o n
1 2 3
Hold set to stop logging: L OG
HO L D
o n
T O
L OG
u s e d
o f f
1 2 3
S T O P
12
4. More about the functions of the datalogger
4.1 The LOG function
4.1.1 Logging status displays
Whenever function is pressed while the logger display is blank, the
display will indicate the logging state. This indicates that logging is in
progress and that 123 memory slots have been used so far: L OG
u s e d
o n
1 2 3
Alternatively, the display below indicates that logging has stopped and
that 124 memory slots have been used: L OG
u s e d
o f f
1 2 4
If the START function has been used (see 4.5), the logger waits for a
specific time and date to start logging, and the following is displayed: L OG
u s e d
w a i t i n g
0
Alternatively, this may indicate that externally triggered recording has
been selected (see 4.8.7), in which case logging may be started by an
external trigger (e.g. a m achine switching on).
4.1.2 Used / free memory / number of runs recorded
Whenever the LOG function is entered, press select to scroll through
sub-functions. The first screen displays the number of memory slots
already used for storage of data and header blocks:
L OG
u s e d
o f f
1 0 0
The next screen displays the number of memory slots available for
further logging:
13
L OG
f r e e
o f f
6 4 9 0 0
The number of separate runs already recorded (out of a maximum of
99) is displayed in the last screen. If the logger is logging, then the
current run number is displayed:
L OG
r u n
o f f
3
4.1.3 Start/stop logging
If you have just unpacked your datalogger and have not previously used
this model then please go to section 3. Whenever you first enter the
LOG function you can press and hold set to start and stop logging: L OG o f f
u s e d
1 2 3 4 5
L OG o n
u s e d
1 2 3 4 5
N.B. you can only start and stop logging when the display shows either
of these screens.
4.1.4 How to clear the memory
The procedure for clearing the memory has been designed to reduce
the risk of the user accidentally clearing the memory. It is not possible
to clear the memory while either logging or waiting to log. It is only
possible to clear the memory using the following sequence:
Press function to wake up the datalogger and press select within 10
seconds to obtain either of the following displays: L OG
f r e e
o f f
1 2 3 4 5
L OG
o f f
14
r u n
3
Now you can clear the memory by pressing and holding set for 2
seconds: L OG
HO L D
o f f
T O C L E A R
4.2 The METER function
This displays the value of the selected channel using the currently
selected range for that channel. As soon as you enter the METER
function, the display will show the value of the first channel selected and
these values will be updated every second. This example assumes you
have selected the following channels: Channel 3
Channel 5
Channel 7
-30.0/70.0 °C
0.000/1.000 V
0.0/5.0V=0/500 Lux
As soon as you enter the METER function, the display will show: M E T E R
c h
3
3 7 . 5
° C
You may view the other channels by pressing select to scroll through
those that have been selected:
M E T E R
c h
5
0 . 3 4 0
V
M ET E R
c h
7
5 2 . 9
L u x
4.2.1 Pulse count channels
When viewing a pulse count channel in METER mode, the display will
show an accumulating total of pulse counts. This total may be reset to
zero by pressing set. Please note that zero reset will not be available
when logging is in progress; in this case, the accumulating total will be
15
automatically set to zero at the beginning of each logging interval. See
section 4.9.3 for further details.
4.2.2 Event/digital channels
The display will either show binary or decimal format, depending on
which has been selected in CHANNEL SETUP. See section 4.9.4 for
further details.
4.2.3 Elapsed time between events
An additional channel is automatically selected when you have selected
the following logging modes: - (See section 4.8 for further details)
M O D E
e v e n t
l o g
M O D E
l o g
e v e n t + i n t e r v a l
M O D E
l o g
e v e n t + a v e r a g e
M O D E
e x t e r n a l
t r i g g e r
r e c o r d s
This additional channel (which numerically follows the last physical
channel) is for measuring time between recordings. The number of
seconds that have elapsed between events or external triggers will be
displayed in this channel and may be viewed in METER mode: M E T E R
c h
1 2 3
s
1 1
4.3 The REVIEW function
The display shows the recorded value of the selected channel, starting
with the first reading in the most recent run or the first reading in the
current run if logging is in progress. Press select to choose which
channel you wish to review. Once the channel has been selected, each
press of set will update the readings from first to last. A rotating bar
indicates that the next reading has been selected: -
16
R E V I E W
c h
2
2 0 . 3
° C
-
R E V I E W
c h
2
2 0 . 2
° C
\
R E V I E W
c h
2
2 0 . 4
° C
|
Holding down set will display the readings rapidly until the following is
displayed: R E V I E W
c h
N o m o r e
2
At any time you may skip to another channel and restart the review by
pressing select.
4.4 The TIME and date function
This displays the real time and date on two lines. The time clock is in a
24 hour format (HH:MM:SS). The format of the date may be changed
for using the STAT function. Please see section 3.1 for details of how to
set the time and date. Although invalid times and dates are allowed to
be set, when function is pressed, the entries are validated. The logger
modifies the entries to the nearest valid setting and displays a warning
that the initial entries were invalid. For example, the following would
occur in UK date format i.e. DD/MM/YY: T I ME
d a t e
1 0 : 4 3 : 1 7
2 5 / 1 3 / 9 4
T I ME
I N V A L I D
1 0 : 4 3 : 1 7
C H E C K !
T I ME
d a t e
1 0 : 4 3 : 1 7
2 5 / 1 2 / 9 4
17
The time and date cannot be altered if logging is in progress. Pressing
set will indicate this to the user:
T I ME
L OGG I N G
1 0 : 4 4 : 3 4
4.5 The delayed START function
This function is used if you wish to set a future time and date at which
logging will start. Once you are in this function, press and hold set until
you obtain a cursor: S T A R T
0 0 : 0 0 : 0 0
0 1 / 0 1 / 9 4
Now press select to place the cursor under the entries that you need to
change: S T A R T
0 0 : 0 1 : 0 0
0 1 / 0 1 / 9 4
This entry may now be changed by pressing set until the desired value
is achieved: S T A R T
0 0 : 0 5 : 0 0
0 1 / 0 1 / 9 4
Other entries may be changed in a similar way, using select and set.
When the desired delayed start time and date has been set, you can
press function to store these parameters: S T A R T
0 0 : 0 5 : 5 5
3 1 / 1 2 / 9 4
It will usually be the case that the start time will be later than the current
real time and the logger will wait until the start time before commencing
logging. In this case, the following message will be displayed: -
18
S T A R T
d e l a y e d
0 0 : 0 5 : 5 5
s t a r t
N.B. Remember that you must also set the logger to start logging
in the LOG function (see 4.1.3). If you have set the start t ime and date
to earlier than the current real time then the following message is
displayed: S T A R T
0 0 : 0 5 : 5 5
i mm e d i a t e
s t a r t
Logging will then commence as soon as you set the logger to start
logging. At this time, the start time will automatically be adjusted to the
current real time. The start time and date cannot be altered if logging is
in progress or if the logger is waiting to start logging; this will be
indicated by the following message when set is pressed: S T A R T
L OGG I N G
0 0 : 0 5 : 5 5
Please note that invalid settings are treated as for time and date.
4.6 The INT function (logging/sampling interval)
Depending upon the logging mode selected (see 4.8), readings may be
stored in memory at fixed intervals or when certain events occur or a
combination of both of these. In the INT function the logging interval is
shown on the top line and can be set between 1 second and 24 hours
(unless ‘fast logging mode’ is used – see section 13). In logging modes
that include averaging, the inputs are measured at a shorter interval
(called the sample interval) and the average of these measurements is
recorded at the logging interval. The sample interval is shown on the
bottom line and can be set between 1 second and 12 hours provided
that a logging mode including averaging is selected: M O D E
l o g
a v e r a g e
M O D E
l o g
19
e v e n t + a v e r a g e
If you have already selected either of the above modes but have not
selected a sampling interval, the following will be displayed: I N T
l o g
1 2 : 0 0 : 0 0
C H E C K
I N T E R V A L S
The logger will then automatically select a sampling interval of 1 second
for logging intervals up to and including 12 hours: I N T
l o g
s a m p l e
1 2 : 0 0 : 0 0
0 0 : 0 0 : 0 1
A sampling interval of 2 seconds is the minimum for logging intervals
over 12 hours. It is not necessary to change the sampling interval if
recordings are made in non-average logging modes. The sampling
interval will be automatically set to zero: I N T
l o g
s a m p l e
1 2 : 0 0 : 0 0
0 0 : 0 0 : 0 0
Please note that the logging/sampling interval cannot be changed while
logging is in progress or while logging is waiting to commence:
I N T
l o g
L OGG I N G
1 2 : 0 0 : 0 0
4.7 The OUTPUT function
This function is used to output data to a computer using the following
programs: Data transfer and setup
Darca Lite
Data transfer and analysis
Darca Plus / Squirrelwise
Data transfer, direct/remote setup and analysis
Darca Plus
Once you enter OUTPUT the display will clear and the datalogger will
quickly enter sleep mode, which is required prior to active
20
communication. The baud rate is automatically selected by the program
that is used. Eltek Squirrels with serial numbers 6000 and above will
work at up to 38400 baud, where as Grant Squirrels will work at up to
19200 baud. During downloading, the number of blocks to be
downloaded is displayed and this number changes after each successful
transmission of a block. While not actively communicating, “idle” is
displayed. An example of some of the displays which may be seen
during the downloading process are shown below:
OU T P U T
9 6 0 0
c o mm s
b l o c k
b a u d
6
OU T P U T
i d l e
9 6 0 0
b a u d
OU T P U T
9 6 0 0
c o mm s
b l o c k
b a u d
5
The number of blocks transmitted will decrement until the display clears
to indicate that all the data have been transferred. Please note that
downloading of data can be achieved while logging is in progress and
that the following minimum logging intervals are permissible,
corresponding to the appropriate baud rates: Baud rate
300
1200
2400
4800 - 38400
Minimum logging interval
10 seconds
3 seconds
2 seconds
1 second
4.8 The MODE function
Once you have entered this function using the function button, press
select to select from the following sub-functions. (Please note that you
cannot change any entries in the MODE function while logging is in
progress or while readings are still stored in the memory).
4.8.1 Mode log
Press set to change the type of logging required from the following
options. Note GenII loggers use Interval logging only.
21
4.8.2 Interval logging
M O D E
l o g
i n t e r v a l
The inputs from each channel selected are measured at each logging
interval and stored in memory. Pulse inputs record the total number of
pulses received during this interval. The logger records the first
readings as soon as logging is started, although pulse inputs record a
dummy value at this point. Please see section 3.2 for instructions on
how to change logging intervals.
4.8.3 Logging averages
M O D E
l o g
a v e r a g e
In this option, the inputs from each channel selected are measured at
each sample interval, which is set at a shorter interval than the logging
interval. All the sample interval readings taken within the logging
interval period are averaged. This average is then recorded at each
logging interval. Readings from pulse count channels and event/digital
channels cannot be averaged and the actual values at the end of the
logging interval are stored. Please see section 3.2 for instructions on
how to change sample intervals. After any change between interval and
average modes, the following will be displayed as a reminder: M O D E
C H E C K
l o g
I N T E R V A L S
4.8.4 Logging events only
M O D E
e v e n t
l o g
The event inputs are monitored every second irrespective of log and
sample intervals selected. Whenever any of the eight inputs of a
event/digital channel change between LOW (less than 0.5V DC) and
22
HIGH (between 4V and 5V DC) voltage levels or between contact and
no contact, the following occurs: a) the state of each of the eight event lines is recorded together with
the time and date of the event.
b) readings are also taken and stored from all other channels which
have been set to log.
c) if a pulse channel has been selected then the number of pulses
accumulated since the last event will also be recorded.
If no event occurs during any 18-hour period then a ‘dummy’ or
‘confidence’ recording is made. See section 4.9.4 for further details
about event channels. Please note that logging must be started in the
usual way by pressing set in the LOG function (see section 3.5). In this
example, only two event lines are being used. A recording is made
whenever an event occurs, which is whenever either event line changes
level: voltage
high
contacts
open
low
contacts
closed
contacts
open
high
event
event
event
event
event
event
contacts
closed
time
event
event
low
4.8.5 Interval logging with events
M O D E
l o g
e v e n t + i n t e r v a l
This is a combination of event and interval recordings and therefore
readings are taken at the end of each recording interval and each time
23
any event input changes state. If events coincide with the logging
interval then two sets of recordings are made. Pulse inputs record a
‘dummy’ value when events occur and true accumulated values are only
recorded after each recording interval.
4.8.6 Logging averages with events
M O D E
l o g
e v e n t + a v e r a g e
This is a combination of event and average recordings. Averaging
occurs exactly as in section 4.8.3 and event recordings allow nonaveraged values of the selected channels to be recorded whenever an
event occurs (see 4.8.4). Pulse inputs record a ‘dummy’ value when
events occur and true accumulated values are only recorded after each
recording interval.
4.8.7 External trigger MODE
In this mode, logging can be started and stopped by external signals.
Press set to change to the f ollowing available options: 4.8.8 Externally triggered multiple runs
M O D E
e x t e r n a l
t r i g g e r
r u n s
Logging is started in the usual way by pressing set in the LOG function
(see 3.5). The logger only records when the external trigger is present.
Readings will be taken from each of the channels selected (in whichever
logging mode has been selected - see 4.8.1). A new run is started
whenever the external trigger is re-applied and recording will stop after
the 99th run or when the memory is full.
24
voltage
high
contacts
open
low
contacts
closed
time
run 1
run 2
4.8.9 External triggering in a single run
M O D E
e x t e r n a l
t r i g g e r
r e c o r d S
Logging is started in the usual way by pressing set in the LOG function
(see 3.5.). The logger only records when the external trigger is present.
Readings will be taken from each of the channels selected (in whichever
logging mode has been selected - see 4.8.1). However, a new run is not
started when the external trigger is re-applied and therefore a complete
record of all externally triggered readings will be recorded in only one
run. This will be of value if you need to analyse these triggered events
on one time axis. The time channel is selected automati cally to log the
time between recordings.
Whenever the trigger is removed, a final dummy recording is made and
then recording stops. If no trigger is applied during any 18-hour period, a
‘dummy’ or ‘confidence’ recording is made.
4.8.10 Wiring up for external triggering
All connections are made to the ‘signal’ connector (15-way male D).
Connect external trigger signal High to pin 14 (external trigger input)
and external trigger signal Low to pin 13 (common - Squirrel ground).
25
voltage
high
contacts
open
low
contacts
closed
time
recording:
enabled
disabled
enabled
disabled
4.8.11 Types of signals wh ich will trigger the logger
If external contacts are used, logging will start when they close
(connecting pin 13 to pin 14), and stop when they open. Alternatively,
voltage levels can be used instead of contacts. In this case, a low level
of less than 0.5V DC will start logging and a high level of between 4V
and 6V DC will stop logging.
4.8.12 Memory mode
You can choose how the memory is used to store the readings.
4.8.13 Hold memory
M O D E
s t o p
m e m o r y
w h e n
f u l l
The logger will stop when all available memory has been used. Note
that you may view remaining free memory at any time by entering the
LOG function and pressing select (see section 4.1.2), and the memory
size may be restricted down to a minimum of 1K in the STAT function
(see section 4.10.3). Note: GenII loggers use only Hold memory.
4.8.14 Continuous memory
M O D E m e m o r y
c o n t i n u o u s
The logger overwrites the oldest recordings once the memory is full.
This ensures that you always have the most recent data stored in the
logger irrespective of how long the logger has been logging. However,
26
only one run is allowed and if the logger is stopped and a restart is
attempted the following be displayed: L OG
o f f
NO MOR E R U N S
Data can be downloaded at any time (even during logging) without loss
of recordings.
4.9 The CHANNEL SET UP function
This is used to select the channels and set the range for each channel.
Each model has a specified combination of channels, please consult the
data sheet in Section 17 for details of your particular model. Once you
enter this function, you will be informed of the number of channels that
have currently been selected: C H A N N E L
9
u s e d
S E T U P
Pressing select will enable you to scroll through all of the channels.
Some of the channels may not be currently selected, and these will be
indicated as follows: C H
5
n o t
u s e d
Holding down the set button will allow you to set up the channel: C H 5
HO L D
T O
C H A N G E
Then, each time set is pressed, the display will reveal the available
measuring ranges for that channel. Once you have set the appropriate
range for a particular channel, you can at any time press select to view
another channel’s setup status. However, if logging is in progress then it
will not be possible to change the channel setup and the following will
be displayed: -
27
C H 3
L OGG I N G
° C
If logging has stopped, but there are readings stored in memory, it is still
not possible to change channel setup and the following is displayed: C H 6
E U m / s
C A N NO T C H A NG E
In the instance that all channels have been de-selected, the logger will
challenge any attempt to leave the function until at least one channel
has been selected: C H A N N E L
S E T U P
NON E S E L E C T E D
4.9.1 Temperature channels
Please consult the data sheet in Section 17 to confirm which
temperature sensors are compatible with your model of datalogger.
Most temperature sensors provide an output that is non-linear across its
operating temperature range and each model has a built-in, sensor
specific linearisation protocol. Most offer a selection of temperature
ranges relating to the operating range of the specific sensor and may
have separate ranges for variants such as types K and T thermocouples
or 3 and 4 wire platinum resistance sensors. For example, a logger with
thermistor inputs will offer the following ranges: C H
1
- 3 0 . 0
° C
/
7 0 . 0
where the resolution will be 0.1°C, and: C H
1
- 5 0 . 0
° C
/
1 5 0 . 0
where the resolution will be 0.2°C. See section 1 for details of how to
connect thermistor sensors.
28
4.9.2 Voltage / current channels
Normally, these channels may be configured for voltage or current.
There are 18 voltage ranges and 2 current ranges, details of which may
be found in the data sheet in Section 17. These channels have an
additional range called the EU (Engineering Units) range where you can
select specific engineering units (e.g. Lux) and a max/min scale (e.g.
0/500 Lux); the appropriate voltage/current range is then selected from
the existing hardware ranges (e.g. 0/5V). In this example, when the
appropriate channel is selected, the following will be displayed: C H
C H
7
E U
L u x
0 . 0
/
5 0 0 . 0
7
E U V
0 . 0 0 0
/
5 . 0 0 0
The EU range may only be set up using Darca (refer to the price list or
contact your distributor for details). Whenever a voltage/current channel
has not been set up, the initial range is always the default EU range and
is displayed as follows: C H
C H
6
E U %
0 . 0
/
1 0 0 . 0
6
E U
V
0 . 0 0 0
/
1 . 0 0 0
Some loggers are fitted with current-only or voltage-only inputs. In these
cases, only the appropriate ranges are available in the CHANNEL
SETUP function.
4.9.3 Pulse count channel
All models have at least one pulse count channel. Typical applications
are outputs from tipping bucket rain gauges, optical meter readers, etc.
Any sensor offering the following outputs can be monitored: a) Voltage of between 4 and 6V at a pulse width of one microsecond
and a frequency of less than 2 kHz.
29
b) Voltage-free contact with a minimum contact
milliseconds at a maximum frequency of 100 Hz.
time of five
Pulses are counted throughout the logging interval and the accumulated
total is stored at the end of this period. The count is set to zero for the
beginning of the next logging interval. The following ranges are
available for pulse count channels: C H
C H
9
0
/
p u l s e
6 5 0 0 0
9
0 . 0 0
/
k p u l s e
6 5 0 . 0 0
An additional range, called the EU (Engineering Unit) range, may be set
up using Darca. This allows the user to specify engineering units and a
max/min scale (e.g. 0/1300 mm rain) corresponding to either of the
pulse ranges. All data in this channel will, in this example, be stored and
downloaded using mm rain as the unit; mm rain will also be displayed in
METER mode.
4.9.4 Event/digital channel
Each model has at least one event/digital channel. This type of channel
is used to log events or eight bit numbers. There are eight event inputs
available and set is used to select this option: C H
1 0
s t a t e
1 1 1 1 1 1 1 1
This shows the status of all the digital inputs. Each of the eight event
lines is stored either as ‘0’ (contacts closed/voltage low) or as ‘1’
(contacts open/voltage high). The number 0 or 1 is called the state. If
you have selected to log in any of the event modes (see section 4.8.6)
then the last event channel will be automatically selected. A typical
application is the monitoring of the opening and closing of doors.
Another option for event channels is that the eight event inputs are
displayed as a decimal number, and this is selected by pressing set:
30
C H
1 0
0
/
s t a t e
2 5 5
4.10 The STAT function
This function describes the following status information of the logger
and is accessed by pressing select.
4.10.1 Battery life indication
S T A T
8 . 7
b a t t e r y
V
6 5
d a y s
This displays the approximate remaining life of the internal batteries in
days, and the current voltage level of the batteries. The estimated
battery life takes into account the number of channels selected and the
log/sample intervals. The battery life figure will usually decrease if the
number of channels set to log is increased and the logging interval is
decreased. Averaging functions in particular will increase battery
consumption considerably. Temperature fluctuations affect battery
voltage and hence the remaining battery life. The battery life estimate
assumes that the working temperature will be between -20°C and
+65°C. At -30°C, the battery life can be decreased to 10% of normal.
The battery life estimate also takes into account the sensor switch on
time, and assumes that the sensor draws 10 mA.
The memory that stores the data and datalogger settings is protected by
a Lithium coin cell (see 16.5). If “Li” is displayed in the top right hand
corner of the display, then the Lithium coin cell must be replaced.
S T A T
8 . 7
b a t t e r y
L i
V
6 5
d a y s
4.10.2 External power supply
S T A T
8 . 9
e x t
V
s u p p l y
The logger can be used with an external DC supply (e.g. Eltek type
MP12U) and should be used for long-term deployment, averaging, high
31
current demand sensors and when using the logger in METER mode for
prolonged periods. If the external supply fails, the internal batteries
provide backup to keep the memory secure or to continue logging.
4.10.3 Memory size selection
S T A T m e m
2 4 9 K
s i z e
Memory size may be changed within this function. This is particularly
useful if you know how much information you need over a particular
time period and wish to avoid excessive data retrieval and downloading.
If you wish to change the memory size, press and hold set.
Subsequently pressing set will scroll through the available memory
sizes from 1K to 30K in 1K increments and thereafter in 20K
increments. Holding down set will allow you to scroll through the
memory sizes faster.
4.10.4 Sensor power on facility
S T A T
s e n s o r
1 0
s e c o n d s
o n
Some voltage/current channels have additional connections to allow
sensors to be supplied with power from logger. Some models allow this
power to be set at either 9V DC or 5V DC. This setting can be changed
only by dismantling the logger and moving the jumpers for each output
as required. See section 16.9 for more information on moving the
jumpers. The 9V setting is only approximate. The voltage is that of the
internal batteries (or external power supply, if present). The 5V DC is
accurate to ±0.1%. Some sensors need to be switched on prior to
measurement for a minimum length of time to allow the output to
stabilise.
This facility allows you to switch the sensor on between 1 second and 60
seconds (in 1-second increments) prior to measurement; all sensor
power outputs will turn on together. The maximum total current
available is 50 mA. If you have more than 1 sensor connected which
needs this facility then you must choose the longest sensor switch on
time required. The sensor switch on time may be changed by pressing
32
and holding set; subsequent presses will allow you to scroll through the
values. Holding down set will allow you to scroll through the values
faster. A value of 0 seconds switches the sensor power on 10
milliseconds before the first channel is read.
Please note that in logging modes which combine event with interval or
average logging, the ‘sensor on’ time is measured with respect to the
fixed interval or sample time respectively. Therefore, no particular
‘sensor on’ time can be guaranteed for the event recordings. However,
in ‘event only’ logging, any non-zero ‘sensor-on’ time setting causes the
sensor power output to be on continuously.
N.B. The ‘sensor on’ time should be set to zero when not required as
otherwise battery life will be wasted.
4.10.5 Date format selection
S T A T
d a t e
f o r m a t
D D / MM / Y Y
The date format is shown in the UK default format; the following formats
are also available and may be changed by pressing and holding set:
S T A T
d a t e
f o r m a t
Y Y / MM / D D
S T A T
d a t e
f o r m a t
MM / D D / Y Y
4.10.6 Language format selection
S T A T
l a n g u a g e
E n g l i s h
This displays the language format, which is changed by pressing and
holding set. The following are examples of the above display in the
relevant language: S T A T U S S p r a c h e
D e u t s c h
33
E T A T
l a n g u e
F r a n c a i s
4.10.7 Mains filter frequency
S T A T
f i l t e r
5 0 H z
The mains filter frequency is displayed. This must be set to the local
mains electricity supply frequency to produce the most accurate
readings. The frequency is changed using the set button; press and hold
to change the filter frequency to 60 Hz.
4.10.8 Logger firmware version and model type
This displays the model number and version of firmware followed by the
serial number of the 1000 series Squirrel datalogger.
4.10.9 Temperature Units
This function enables you to change the temperature units in the
Squirrel between degrees Fahrenheit and Celsius.
4.10.10 (RS232) Network Option
Multiple Squirrels (equipped with this option) can be connected in
parallel. This in referred to as “network”. Note a special connecting
cable is required.
The option must be ON for (RS232) Network functionality and OFF if
not required. The Network setting in Darca must be configured to
correspond with this setting in order to communicate with the Squirrel.
Note “Network Option” does not refer to Ethernet connectivity.
34
5. Making connections to the datalogger
Your 1000 Series Squirrel datalogger has a fixed channel
configuration. Please refer to the datasheet in Section 17
to determine which of the following are relevant.
5.1 Wiring up thermistor sensors
Individual plug-in terminal blocks with cable restraints are provided to
make the connections to the inputs on the datalogger. Thermistors are
always connected to adjacent pins and often have no designating
letters, since they have no polarity.
thermistor
thermistor
thermistor
sensor
sensor
sensor
o
v c
t o t o
Note: The ‘-’ denotes the ground connection. This should be connected
to the cable screen, if any.
5.2 Wiring up pla tinum resistance sensors
Individual plug-in terminal blocks with cable restraints are provided to
make the connections to the inputs on the datalogger. 1000 Series
loggers support both 3 and 4 wire PT100 sensors, and may be marked
in either of the two ways shown below.
35
sensor
sensor
c v v c
3 wire connection
sensor
sensor
c v v c
4 wire connection
N.B. It is essential for 3 wire sensors that the resistances of all the
connections are equal, i.e. the wires used for these connections should
be of the same material, gauge and length. This allows the circuit to
cancel the effects of lead resistance on the sensor measurement.
5.3 Wiring up se nsors to voltage channels
Individual plug-in terminal blocks with cable restraints are provided to
make the connections to the inputs on the datalogger. The positive
output from the sensor should be connected to the ‘v’ input and the
negative to the ‘-’ input: -
36
sensor output
o
sensor output
v c
v c
sensor output
sensor output
c v o
v
Note: if the cable used has an independent screen, this may be
connected to the ground term inal, which is marked ‘o’.
5.4 Wiring up se nsors to current channels
Individual plug-in terminal blocks with cable restraints are provided to
make the connections to the inputs on the datalogger. The connections
are the same as for voltage with the addition of a link between the ‘c’
and ‘v’ inputs: sensor output
sensor output
o
v c
v c
37
sensor output
sensor output
c v o
cv o
5.5 How to provide a power supply to the sensors
Each voltage/current channel has its own connections to allow sensors
to be supplied with power at 5V DC or 9V DC. By default, the voltage
will be at approximately 9V DC. The exact voltage will depend on the
state of the internal batteries or the voltage of the external power
supply, if present. Some models have the option to change the sensor
power to 5V DC (±0.1%). This is dealt with in section 4.10.4. The
maximum total current available is 50 mA. Section 4.10.4 describes the
logger setup procedure to switch power to the sensors prior to
measurement. The following diagram shows how to connect the sensor
to the switched sensor power supply: -
power to sensor
o
power to sensor
c v o
v c
38
5.6 Wiring Up Current Loop Sensors driven by t he
Squirrel
sensor output
o
v c
5.7 Wiring up an AC voltage input
AC inputs have either 3 or 5 pin DIN sockets for connecting a range of
different sensors. Rogowski coils, Voltage Transducers and Current
Transducers can be connected to any of the AC voltage inputs. Some
inputs also allow thermistors to be connected.
Sensor output
AC
Sensor output
AC channel n
AC n+1
AC n+2
thermistor
sensor
Note: the ‘-’ connection is ground and should be connected to the cable
screen, if any.
39
5.8 Wiring up a p ulse count channel
Pulse count channels may be wired for a voltage input or a voltage-free
contact (see section 4.9.3 for details of voltages and mechanical contact
conditions). The positive connection should be made to the ‘+’ input and
the negative to the ‘-’ input. For a voltage-free contact input, the contact
‘debounce’ circuit must be connected. This involves linking the ‘-’ pin to
the ‘s’ pin: sensor output
sensor
s
s
Note: the ‘-’ connection is ground and should be connected to the cable
screen, if any.
40
5.9 Wiring up event channels
Any or all of the eight event inputs on the ‘signal’ connector (15-way
male D) may be connected (via a contact or signal source) to one of the
common ground pins, as indicated in the following diagram: common ground
13
or
9
8 7 6 5 4 3 2 1
individual event inputs
If any of the connected event channels change state, then this will
constitute an event.
The above diagram shows all events being monitored using contact
closures, but events may also be monitored using changes in voltage
levels (see 4.8.4). 1000 Series loggers with additional event channels
will have a 10 way terminal block. Inputs may be connected via a
contact to one of the common ground pins, as indicated in the following
diagram: common
individual event inputs ground
1 2 3 4 5 6 7 8 GND
In both cases, if the maximum voltage could exceed 5V, then the
addition of a 1K resistor in series with the input will allow voltages up to
6V to be used.
41
5.10 Wiring up for external triggers
Logging can be started or stopped by an external signal. This external
signal can be in the form of a voltage or a contact and should be
connected between pin 14 and common ground. See 4.8.11 for further
information.
common ground
external
13 or
9
trigger
42
6. Troubleshooting guide
6.1 “Why won’t it do that?”
Having described the many things you can do with a 1000 Series
Squirrel, here are just a few operations that are not possible: ·
·
·
·
·
·
·
·
clear the memory while logging is in progress
start logging when the memory is full
start logging if no channels have been selected
perform multiple runs if memory is in continuous mode
reset pulse count while logging is in progress
change date and time while logging
change start date and time while logging
change log and sample intervals while logging
It is not possible to change the following either when there are readings
stored in memory or when logging is in progress:
·
·
·
·
·
·
·
·
·
·
Log mode
External trigger mode
Memory mode
Channel set up and ranges
Engineering unit ranges
Memory size
Language type
Sensor switch on time
Date format
Filter frequency
43
7. Memory Card Squirrels
Memory Card Squirrels have a slot in the front for a low power PCMCIA
SRAM card of between 128Kb and 4Mb in size. The Squirrel can log
directly onto the card, or copy runs onto it from its internal memory. A
Windows file system allows direct access to Squirrel data from a PC.
7.1 Types Of Card
Not all types of SRAM card are compatible with the Squirrel. The
following manufactures of card have been tested and are
recommended:
· Panasonic
· Mitsubishi
· King Max
· Pretec
Other cards may be compatible but could result in excessive current
consumption.
7.2 Preparing the Card
Before the Squirrel can use the card, it must be formatted and then
prepared with Darca’s ‘Memory Card Utils’ feature.
Note: If your SRAM card does not appear as a Removable Drive in
Windows Explorer, you must configure Windows to read SRAM cards
with your card holder. Search for ‘SRAM’ in Windows Help for
information on how to do this.
7.2.1 Formatting the card
Open Darca’s ‘Memory Card Utils’ feature (it is accessed from the File
menu). Your SRAM card will appear under the list of ‘Removable
Drives’, with corresponding status information in the three boxes to the
right. Click the ‘Format Drive’ button to open Windows’ Format utility.
Use the ‘Start’ button to format the card as you would a floppy disk (do
not worry that the type of format is set to ‘Quick’).
7.2.2 Preparing the card
Before the Squirrel can store data on the Memory Card, the card must
be ‘prepared’ by creating a file on it to hold the data. Use the ‘Prepare’
button to create this file (it will be named ‘Squirrel.tad’). Check that the
size of this file corresponds to the size of the Memory Card.
44
7.3 Squirrel Settings
An additional function has been added to the Squirrel. This controls the
use of the memory card, and is the only place where a card should be
inserted or rem oved. The function consists of three sub-pages.
7.3.1 Card size
Before inserting a memory card, the display will show the following:
C A R D
a b s e n t
i n s e r t
c a r d
h e r e
This tells you that this is the point where a card may be inserted. Until
this is done, pressing the select button will not display the next page of
the function. Once a card is inserted, its size is calculated and
displayed:
C A R D
s i z e
p r e s e n t
1 0 4 0 K
The card size displayed is a calculation of how many thousand readings
can be stored on it. Note that this is approximately half the number of
kilobytes on the card. This is also the point where a used card may be
removed.
Cards may also be erased in this function. If you have inserted a card
that contains Squirrel data, but you wish to clear it in order to record a
new run onto it, press and hold the set button. The display will show the
following:
C A R D
H O L D
p r e s e n t
T O C L E A R
If the size of the card is not displayed, it is due to one or more
problems. The nature of the problem is clearly stated on the display:
C A R D
F I L E
p r e s e n t
N O T
F O U N D !
45
In this example, the Squirrel has found that the card has not been
properly prepared with the SQPrep utility. Until this is done successfully,
the logger cannot use the card. If the display shows ‘REPLACE
BATTERY!’ then the battery is starting to fail and should be replace as
soon as possible. If the display shows ‘BATTERY DEAD!’ and there is
important data in the card, then you should replace the battery before
removing the card from the logger. ‘WRITE PROTECTED!’ is displayed
if the Write Protect switch on the card is on. The logger cannot write to
the card while it is write protected, so this should be switched off.
Once the Squirrel is configured to use the card rather than the memory,
the following will be displayed:
C A R D
s i z e
i n
u s e
1 0 4 0 K
This tells you of the status of the card, and reminds you not to remove
the card.
7.3.2 Choose memory
Pressing the select button again will display the memory selection page.
This is where you can choose whether the internal memory or the
memory card should be used when logging. This screen also displays
information about any data stored on the card. In this example, the card
has no Squirrel data in it.
C A R D
e m p t y
u s i n g m e m o r y
If there is any Squirrel data present in the card, then the display will
show the following:
C A R D
h o l d s
d a t a
u s i n g m e m o r y
46
By default, the internal memory is used. If you have inserted a blank
formatted card onto which you would like to log, then this is probably the
only setting that needs changing. Press and hold the set button to switch
between the internal memory and the memory card.
C A R D
H O L D
e m p t y
T O C H A N G E
The display will then show the following:
C A R D
e m p t y
u s i n g
c a r d
If there is already Squirrel data in the card, then the display will show
the following warning instead of the usual ‘HOLD TO CHANGE’
message:
C A R D
c h o o s e m e m
O V E RWR I T E C A R D ?
N.B. Neither this function nor the next can be accessed while the
Squirrel is logging to the card.
7.3.3 Copy readings
It is sometimes more convenient to copy a set of readings to the card
rather than to actually log to the card. The final CARD function
facilitates this. Press and hold the set button to copy all the readings to
the memory card.
C A R D
c o p y
b a c k u p
t o
d a t a
c a r d ?
While copying, the display shows a message to that effect. Copying
data can take as long as 4 minutes for a 2Mb card, or just 15 seconds
for a 128Kb card.
C A R D
c o p y
d a t a
c o p y i n g
d a t a
47
If the card already contains data, the same ‘OVERWRITE CARD?’
message will appear. It is possible to copy to the card while the Squirrel
is logging to its internal memory, though this may take longer.
Note that this function cannot be accessed while the Squirrel has been
set up to use the memory card instead of its internal memory.
7.4 Extracting the data
7.4.1 Introduction
The data in the SRAM card can be extracted in two ways. It can be
downloaded in the normal way, or the memory card can be removed
and inserted into a computer where the data can be copied directly onto
the hard disk. The second method is performed using the ‘File
Conversion’ tab in Darca’s Memory Card Utils.
7.4.2 File Conversion
Once the card is in the PC, the data can be copied and processed by
the File Conversion utility.
· Select the ‘Squirrel.tad’ file from your SRAM card with the first
‘Browse’ button. The filename will appear in the ‘Selected TAD File’
box.
· Choose the name and location of the DAT file that you want the
data to be stored in with the second ‘Browse’ button.
· Click the ‘Convert’ button to copy the data from the SRAM card and
store it on your PC as the chosen DAT file.
48
8. Electricity Squirrels (1010, 1020)
Electricity Squirrels have inputs for AC transducers, like Rogowski coils,
current and voltage transducers. An extra function in the Squirrel allows
easy reviewing of the maximum logged values stored on each channel.
Additionally, the last two channels out of every eight can be used for
temperature probes.
8.1 Logger functions
8.1.1 Intervals
Due to the long settling times when measuring AC, the Squirrel’s
minimum log or scan interval is increased to 5 seconds when more than
one analogue channel is selected. Selecting digital channels does not
affect this minimum interval.
8.1.2 Maximum
While logging, the Squirrel monitors each selected channel for peak
values. This function allows the user to review the maximum logged
value on each channel.
M A X I MUM
2 4 8 . 8
c h
V
1
Along with the maximum value of the channel, the time at which it
occurred is also stored. If the same peak value occurs more than once,
then the time stored is that of the most recent peak. To view the time at
which the maximum occurred, press the set button:
M A X I MUM
c h
1
2 5 / 0 3 / 9 6
1 1 : 5 4
The maximum on the next channel can be viewed by pressing the
select button.
8.2 Selecting ranges
Ensure that the range selected is correct for the type of transducer
connected to the input - i.e. the 0 to 1000A CT range must not be used
for a Rogowski coil and vice-versa. Note that AC ranges that start at 0
49
only achieve 0.1% accuracy at above 1.2% of scale.
8.2.1 Ranges
A completely new set of analogue ranges is implemented on the 1010: 1010
1-8
1020
1-16
Input type
AC Transducer
Available ranges
0 to 200A coil
0 to 500A coil
0 to 1000A coil
0 to 2000A coil
0 to 1000A CT
0 to 300V
170 to 270V
Resolution
0.2A
0.5A
1A
2A
1A
0.3V
0.1V
7&8
7 & 8, 15 &16
Thermistor
-25.0 to 125.0°C
0.1°C
9
17
Pulse count
0 to 65,000
0 to 650,000
1
10
10
18
Digital
State
0 to 255
00000000 to 11111111
8.3 Making connections to the datalogger
It is possible to connect many different types of sensors to the 1010
Squirrel Datalogger. These include Rogowski coils, miniature CT’s (1A,
5A, 7.5A), VTS and VTP voltage transducers and air & surface
temperature sensors. This is our standard range, though other
transducers may be available to order.
50
9. Squirrels with pH channels
Some Squirrels have pH inputs. Such inputs require individual two-point
calibration, and temperature compensation. The Squirrel supports two
types of temperature compensation - measured and pre-set.
9.1 Channel Selection
The pH channels have two ranges available. These are actually both
the same range; the difference is where the temperature compensation
comes from. Choose from the pre-set temperature (which can be
altered in the STAT function), or from the associated temperature
channel (as illustrated below). If the latter is chosen, one of the -50°C to
+150°C ranges of the temperature channel must also be selected
otherwise the logger will perceive this as an error and switch the range
to use the pre-set compensation. In this situation, the display will show
‘INVALID – CHECK!’ to alert the user that this has happened.
C H
9
0 . 0
p H
/
( c h 1 )
1 4 . 0
It is worth noting that if the temperature channel is selected but no
probe is plugged in, then compensation will again be taken from the
pre-set value. In this case, the pH ‘range’ is unchanged; the temperature
input would still be used if it were connected.
9.2 Pre-setting the Temperature
If the temperature of all the pH probes is known to be constant (or if
high accuracy is not required) then it is not necessary to use a
temperature probe for compensating the pH probe. The temperature of
the pH probe can be set in the STAT function.
S T A T
p H
2 0 . 0
t e m p
° C
Press and hold set to change the value. The longer set is pressed the
faster the value changes.
51
9.3 Choosing t he Calibration Point
Calibration of the pH probes requires two buffer solutions. One must be
pH 7.0; the other may be pH 4.0, 9.0 or 10.0. The other extra STAT
function is for setting the pH of this second buffer solution.
S T A T
p H
4 . 0 0
s l o p e
Press and hold set to change the value.
9.4 Calibrating the Midpoint (pH7.0)
Before any sensor can be used with the Squirrel, it must be calibrated
using two buffer solutions. An additional CALIBRATION function allows
the setting of both pH 7.0 and pre-selected calibration point (or ‘slope’ see above). Select the CALIBRATION function. After a couple of
seconds, the display will change to show the calibration settings (see
below).
Place each probe individually in a pH7 buffer solution and allow it time
to settle (the time this takes will depend on the probe, and how it has
been stored or used. See ‘Care and Use of pH Probes’, below). If the
temperature compensation is being measured, then the relevant
temperature probe must be put in the same solution.
B U F F E R 7
6 . 6 4
c h
p H
9
2 0 . 0 C
Once the value has settled, the display should show ‘BUFFER7’ in the
top left-hand corner. If it reads ‘O/RANGE’, then the pH input is too far
out of range to be set as the midpoint. This is typically caused by a pH
probe that has expired. Once the probe has settled, press and hold the
set button. ‘HOLD TO CHANGE’ will appear on the display and then the
logger will recalibrate itself on the current channel to read 7.00 pH: B U F F E R 7
7 . 0 0
c h
p H
52
9
2 0 . 0 C
If the display is showing ‘O/RANGE’ when the set button is pressed, the
display will show ‘CANNOT SET’ to indicate that the probe cannot be
calibrated. The Squirrel retains its previous calibration setting. Select
the next pH channel with the select button, and calibrate it in the same
way. This must be done for all the channels that are required.
9.5 Calibrating the Slope
The second calibration point is the slope. The pH of the buffer solution
used in this function should be set in the STAT function, as described
above. Once that is set as desired, calibration of the slope can be
performed in this function. The probes must be rinsed, placed in the
specified buffer solution, and allowed time to settle. If the temperature
compensation is being measured, then the temperature probes must be
put in the same solution.
S L O P E 9
9 . 3 1
c h
p H
9
Once the probes have settled, the display should show ‘SLOPEn’
(where ‘n’ is 4, 9 or 10). If this does not match the solution that is being
used, then the slope value in the STAT function must be changed
appropriately (see above). If it reads ‘O/RANGE’, then the pH input is
too far out of range of the preset value for the Squirrel to be calibrated
to it. Again, this is typically caused by a pH probe that has expired.
Once the value has settled, press and hold the set button. ‘HOLD TO
CHANGE’ will appear on the display and then the logger will recalibrate
itself on the current channel to read the correct value (in this example,
9.00 pH): S L O P E 9
9 . 0 0
c h
p H
9
If the display is showing ‘O/RANGE’ when the set button is pressed, the
display will show ‘CANNOT SET’ to indicate that the probe cannot be
calibrated. The Squirrel retains its previous calibration setting. Select
the next pH channel with the select button, and calibrate it in the same
way. This must be done for all the channels that are required.
53
9.6 Current Consumption and Battery Life
Due to the sensitive nature of pH probes, the Squirrel has to provide a
constant power supply to the pH input circuitry when pH inputs are in
use. This power supply is switched on when one or more of the pH
channels are selected for metering or recording. If the logger is not
recording or waiting for a delayed start, the power supply is switched off
at midnight.
This power supply is the reason for the decreased battery life. This is
reflected in the displayed battery life in the STAT function.
9.7 Care and Use of pH Probes
pH probes are very sensitive. Depending on their age and history, they
can take a while before settling on a value. During probe calibration,
each pH probe should be allowed enough time to settle. Always wait
until the reading to stays constant for ten seconds. This is usually fairly
quick, but old probes, probes that have been allowed to dry out, and
probes that have been in either a very high or very low pH may take a
while to settle. Occasionally, the output of a probe may continue to
wander, never really settling on a value. This is an indication that the
probe has expired and should be replaced.
As explained in the above section, the logger will power down its pH
input circuitry under certain conditions. When this happens, any pH
probes that may be connected will deteriorate more quickly than normal,
so it is strongly recommended that any pH probes be disconnected and
stored properly when not in use.
The tip of a pH probe should always be kept wet, so there are some
important points to remember when storing one. After use, the tip of the
sensor should be rinsed in pH 7.0 buffer solution. The end cap should
then be sealed on while the tip is still wet.
These actions should help to preserve the life of the probe, and make
for speedier calibration when it is next used.
54
10. Special Instructions
This section contains instructions for special 1000 Series Loggers, so do
not necessarily apply to your Squirrel(s).
10.1 Alarms
· High and low alarms individually configurable on each channel.
· The alarm output is asserted, and the relay contact is closed,
whenever any channel is in an alarm state while logging.
10.1.1 Squirrel settings
Low Alarm
For each selected channel, a lower alarm threshold can be set or unset.
By default, no value is set.
L OW
A L A RM c h
- - - ° C
1
To select the channel, on which you require an alarm condition, press
select until the required channel is displayed. Then press and hold set to
enter the edit mode.
L OW A L A R M c h
1
H O L D T O C H A N G E
A lower alarm threshold will appear for editing. The value used will be
the value that was last used by this channel before it was unset. If there
has never been an alarm set on this channel or if the previous value is
not valid for the current range, then the bottom of the current range will
be substituted. Use the select button to move the cursor, and the set
button to change the v alue.
L OW A L A R M c h
- 3 0 . 0
° C
55
1
To remov e the alarm setting, enter an illegal value. Any setting that the
Squirrel can make no sense of will cause the lower alarm threshold to
become inactive, e.g., two minuses: L OW A L A R M c h
- - 0 . 0
° C
1
When editing is complete, press the function button to leave the edit
mode. The setting will be validated and redisplayed. To re-edit, press
and hold the set button again. To move onto the next channel, press
select. The alarm appears on pin 10 of the ‘signal’ connector.
High Alarm
Operation of this function is identical to the Low Alarm function
described above.
Meter
When metering, the display will show two asterisks when you are
viewing a channel that is currently in an alarm condition:
M E T E R
c h
3
3 7 . 5
° C
* *
This is helpful in finding the channel that is causing the alarm.
10.2 Wind Speed & Direction
Special circular averaging on EU range for wind direction.
10.2.1 Wind Direction
Squirrels with Wind Direction inputs have a specially configured EU
range on the last voltage channel. This is set to a hardware range of 05V dc and will read 0° to 360° for this input. The direction is also
displayed as N, WSW, etc.
10.2.2 Averaging
A special averaging mode is implemented on channel 8. When wind
direction is being measured and the Log Mode is set to Average then
the logger will sample as normal at the scanning interval. Each reading
that is calculated from these samples is a true circular average - it is not
56
averaged as 0-5V dc as this would cause an erroneous readings under
certain conditions (e.g. When the direction varied around North - say
375° to 5° - the mathematical average would be 180° which is South!).
10.2.3 Wind Speed
Sometimes, another specially configured EU range can be found on the
last but one voltage channel. This is set to a hardware range of 0-5V dc
-1
and will read 0 to 154.3ms for this input.
57
11. Modems
It is very important to correctly configure the modem that is going to be
connected to the Squirrel. Most problems involving Darca and modems
can usually be traced to the Squirrel’s modem not being set up.
Connect the modem directly to the computer using the RS 232 port,
which is usually at the back of your computer and labelled Comm 1 or
Comm 2. To configure this modem you will need to use a simple
terminal emulation program such as Windows Terminal. You can then
send ‘AT commands’ to the modem in order to configure it in the way
you require. When using such a program, be sure to set it to the correct
Comm port, and to the baud rate which you will be using once the
modem is con nected to the Squirrel.
Unfortunately, as each manufacturer has their own version of the AT
command set, this help file cannot list the necessary commands for
your particular modem. However, most modern modems have sensible
defaults and clear instruction manuals.
IMPORT ANT: These guidelines assume that all the modem’s settings
are the ‘factory defaults’. If this modem is brand new, then this is
probably so. If not, look up how to restore the defaults in the modem’s
handbook. On some modems, some of the settings described below
may require a tiny DIP-switch to be set, rather than an AT command to
be sent. Occasionally, a manufacturer will put more than one ‘factory
default’ profile in the modem. In this case, make sure that the profile
has auto-baud rate negotiation and hardware (not software) flow control.
N.B. references to RTS/CTS mean hardware flow control, which is
appropriate. References to XON/XOFF mean software flow control,
which would be unsuitable.
11.1.1 Common AT Commands
These instructions assume you have a new, high-speed modem with a
data input buffer of at least 1k. Most modern modems conform to this
requirement.
58
1. Ensure that the baud rate i n the terminal emulator you are using is
set to a baud rate that i s compatible with the Squirrel. This is
typically between 1200 baud and 9600 baud (the faster the better).
2. Leave the modem’s hardware flow control enabled. The Squirrel
cannot use flow control, but the data packets that it sends are so
small they will fit into the modem’s input buffer without over-filling it
and causing the transmission of flow control signals. The error
correction and data compression can also be left enabled.
3. Since Darca will ultimately be dialling this modem up, it needs to be
told to automatically answer any calls. Thankfully, this is always
done with a particular S-register (S0). So, to set the modem to
answer after 2 rings, the following should be sent:
ATS0=2 [Enter].
Should you require the modem to answer after 4 rings, substitute
the 2 for a 4. Some modems require a DIP-switch to be set to
enable auto answering.
4. This new configuration must be saved in the modem so that
whenever the power to the modem is turned on this new profile will
be used. It is important to m ake sure that the baud rate at which
you send the following command is compatible with your Squirrel
(i.e. 9600 baud or slower for 1000 Series Squirrels), as you are also
storing this baud rate along with the settings that have changed in
points 2 & 3. The exact AT command will depend on your modem,
but is typically:
AT&W [Enter].
or AT&W1 [Enter].
59
12. Model 401/451 and derivatives
The 400 Series Squirrels are simpler 4 channel dataloggers based on
the 1000 Series and retain many of the features of the 1000 Series. The
differences between the 400 and 1000 series are as follows:
Model 451
- The external triggering function has no effect, as there is no input
for an external trigger.
- There is no pulse or event input.
Model 401
- These Squirrels do not have either a display or buttons. Control and
configuration of the Squirrel must be performed with a remote
control program such as Darca.
- The LED flashes periodically (whether or not the Squirrel is logging).
60
13. Fast Logging
13.1 Logging Interval
In order for the Squirrel to operate in fast logging mode, only analogue
channels must be selected. No digital channels may be selected. The
logging mode must be set to Interval, the external trigger mode can be
unused or set to external trigger runs, and the memory mode must be
stop when full. If these conditions are met the Logging Interval
function will look something like this:
I N T
l o g
0 0 : 0 0 : 0 0 . 1
The interval can be altered in the normal way. If ‘fast logging mode’ is
not required, then the tenths of a second should be set to zero. Interval
values up to 9.9 seconds can be set in fast logging mode. It is not
possible to set values greater than this if the tenths are not set to zero.
When logging in fast logging mode, no function other than ‘LOG’ can be
selected. This is true even if the interval is, for example, 8.4 seconds. (If
the interval were 8 seconds or 9 seconds, this restriction would not
apply, as the logger would behave as normal). When in fast logging
mode, the Squirrel can still be stopped and started in the normal way.
· When using an external trigger to start fast recordings, the logger
must either be in the Log function or the display must be off.
· When attempting to start fast logging using the delayed start option,
the logger must be left with the display off.
· The minimum logging interval allowed depends on the number of
selected channels. Allow 0.1 second for every 8 channels.
· Logging intervals of 2, 3, 4, 5, 6, 7, 8, 9 seconds operate as normal
logging.
· Important: Unused channels must be de-selected when logging in
the fast mode. If left selected, the readings on the selected
channels may be slightly inaccurate.
13.2 Translation with Darca
The tenths of a seconds will not be included in the standard time column
as this is not compatible with most spreadsheets. When translating files
61
that have been recorded in fast mode, it is necessary to include the
elapsed time column. To switch it on, select Preferences then Export
and choose Generate Elapsed Time Column.
13.3 Darca Contact
It is not possible to contact the Squirrel (for either controlling or
downloading) while it is logging in ‘fast logging mode’. Logging must first
be stopped using the button on the front of the Squirrel.
62
14. GenII Radio Data Logging System
14.1 Introduction
This GenII information is for systems where programming transmitters is
from the RX250 Receiver Logger.
The GenII radio data logging system records data from sensors located
at some distance from the Receiver Logger (e.g. RX250AL) where
cables would be impractical and expensive. A radio range of 2Km over
open ground is possible. Range or coverage be increased using the
RP250GD repeater.
GenII transmitters can be supplied with a variety of different sensors.
These can be either integral or plugged in. Each transmitter can have
up to 15 channels, which can be spread over more than one type of
input. Up to 250 transmitted channels distributed across a maximum of
125 transmitters can be recorded by one Receiver Logger.
The RX250AL can be used to program each of the transmitters with the
channel set-up, humidity calibration information, and the transmission
interval. All of these settings are stored in the transmitter in non-volatile
memory, so there is no need to re-configure them when the batteries
are changed. (Alternatively Darca Plus can be used to set-up
transmitters).
14.2 Initial Setup
14.2.1 Connections
The MP12/U power supply should be plugged into a mains outlet, and
the other end connected to the socket in the RX250 labelled ‘12V DC
Regulated’. The aerial should be attached SMA antenna socket.
14.2.2 Enabling RX250AL Setup
The RX250 STAT function contains extra pages for configuring the
Squirrel with the transmitter system.
One of these pages prevents the current settings being tampered with
63
by controlling whether changes may be made to the RX250AL and
transmitter configuration. It is found after the ‘mem-size’ page, and
looks like this:
S T A T
s e t u p
D I S A B L E D
Pressing and holding set changes this to ‘ENABLED’. This must be
enabled to carry out any changes to the RX250AL and transmitters’
configuration.
14.2.3 Limiting the Number of Channels
Unlike most Squirrels, the RX250AL does not have a pre-set number of
channels. This is because the system is open-ended and allows the user
to connect any number of transmitters to the RX250AL. The maximum
number of channels is 250. However, a maximum value of the number
of channels to be used must be entered into the RX250. This is so that
the Channel Setup function knows when to wrap around from the last
channel to the first one. This is located in an additional page in the
STAT function:
S T A T m a x - c h a n s
2 0
c h a n n e l s
Press and hold set to change the value to anywhere between 4 and 250
channels.
14.2.4 Transmitter ID
Each transmitter has a unique serial number (found on the label on the
base of the transmitter or displayed if available at power up) which is
used as an identifying code by the RX250AL. It is shown on the
RX250AL display during transmitter related functions, such as Channel
Setup. Every transmitted value is accompanied by this number so that
when the RX250AL receives it, it knows which transmitter has sent it
and can work out which channel the data belongs in.
64
14.3 System Configuration
14.3.1 Transmitter Set-up
An LC-TX, Programming Lead is supplied to connect each transmitter to
the RX250AL ‘output’ connector. The LC-TX has a male 6-pin mini-DIN
at one end, and a 3.5mm stereo jack plug on the other and is used to
connect the RX250AL to each transmitter when setting them up.
Each transmitter must be connected in turn to the RX250AL in order to
configure the channels and set the transmission interval. This process
simultaneously configures both the RX250AL and the transmitter, and
depends on them being connected to each other.
There are three aspects to the set-up:
1. The transmission interval.
2. Selection of the channels to be transmitted.
3. The calibration of the sensors.
These settings can only be changed if the RX250AL is not logging and
has had its memory cleared.
Before attempting to set a transmitter up, install 4 x AA batteries. Now
check that the red LED on the top panel flashes as the power is
applied. After connecting the battery, the transmitter will be in one of
two states. Either the LED will flash briefly every 8 seconds, or it will
flash for slightly longer at the present transmit interval, as it flashes
every time it transmits. From the factory, the transmitters should be
flashing every 8 seconds. This is an indication that the transmitter is not
configured, and serves as a warning that it will not be transmitting any
data.
Now connect the LC-TX. Plug the 6-pin mini-DIN in to the RX250
socket labelled “output” and the 3.5mm jack into the socket located on
the PCB within the transmitter, this is only accessible if the bottom
cover is removed (held in place by two Pozi head screws). The battery
pack can now be carefully withdrawn, but left connected.
14.3.2 Transmission Interval
Setting the interval function, described in Section 4.6, is used on the
RX250AL to set the logging interval. Another page in the “INT mode”
65
has been added to enable the transmission intervals in the transmitters
to be changed. After connecting a transmitter, pressing the select button
enters this sub-functions of “INT mode”, “INT TX” will display the
interval that is currently set in the transmitter that is connected to the
RX250
I N T
T X - 1 2 3 4
t x - i n t
0 : 0 5 : 0 0
If the RX250 fails to find a transmitter connected to the Squirrel, the
display will show the following:
I N T
c o n n e c t
T X
If this is displayed even with a transmitter connected, then the
connections should be checked, as should the state of the battery in the
transmitter.
The default value of the transmission interval is 5 minutes, which is the
recommended value for 30 minute logging interval. The transmission
interval can be changed in exactly the same way as the log or scan
interval is changed in the Squirrel. Once the required value is shown on
the display, the function button must be pressed to transfer the new
setting into the transmitter. The display is then updated to reflect the
new value in the transmitter.
Pressing the function button again will move the RX250AL into the next
function, as usual. Alternatively, if there are a number of transmitters to
configure, another may be connected at this point. The display is
automatically updated to show the new transmitter’s serial number and
transmit interval.
It is worth mentioning that the transmission interval is in fact an
‘average’ transmission interval. The transmission will occur at a random
point during each transmit interval. This minimises the chances of
transmissions from two or more transmitters systematically crashing into
each other. It also means that it can appear to an observer that the gap
between two transmissions can be almost as much as twice the transmit
interval. In this case, a transmitter would be transmitting at the very
beginning of one interval and at the very end of the next.
66
14.3.3 Channel Set-up
As with the standard Squirrel, this function is used to configure the
channels on the system. The difference with the RX250AL is that the
ranges available on any channel will entirely depend on the transmitter
that is connected. Consequently, the RX250AL must be connected to a
transmitter with the programming lead when setting up channels.
Entering Channel Set-up for the first time will show this on the display:
C H A N N E L
0
u s e d
S E T U P
The RX250AL channel is selected in the normal way using the select
button:
C H 1
n o t
c o n f i g u r e d
Pressing the set button steps through the available channels of the
transmitter:
C H 1
T X - 1 2 3 4
- 5 0
/ 1 5 0
° C
A
Here, the RX250AL is showing the current channel configuration for
channel 1. In the middle of the top line of the display, the transmitter
number is displayed.
The ‘A’ on the right hand side of the display shows the selected channel
within the transmitter. Note that the channels of the transmitters are
assigned letters to prevent them being confused with the numbers of the
RX250AL channels.
Pressing the set button again will move the display onto the next
available channel within the transmitter. After several presses, the
display will show ‘not configured’ again. This means that the channel is
switched off, and will not be transmitted or logged.
There are several circumstances where the above display is not shown.
This could happen if, for example, the transmitter is either not
67
functioning, or if it has not been connected to the RX250AL. It is also
possible that the transmitter is already configured, and all its channels
are allocated. In this last situation, the RX250AL will display this:
C H
N O
1
S P A R E
C H A N S
As transmitter channels are assigned to RX250 channels, the number of
available channels within any particular transmitter will drop. This is
because the system prevents the user mistakenly assigning a single
transmitted channel to more than one RX250 channel.
Using this system, there could be circumstances that may leave the
transmitter thinking it is assigned to channels in a RX250, and theRX250
not having those channels assigned within it. A special function is
available in the Squirrel to break this deadlock by deleting such
erroneous assignments - see the section below on “TX Battery and
Reliability”.
Once the Squirrel channels have been assigned to transmitter channels
as required, the Channel Setup function can still be used to browse the
channel setup, even with no transmitter connected. Additionally, the
channels can be switched on and off. Pressing the set button on a
previously setup channel with no transmitter attached will cause the
display to show the following:
C H 1
n o t
l o g g e d
Obviously, the transmitter that was previously set-up to log on this
channel will still be transmitting the data, but changing this setting has
instructed the RX250AL to ignore it. The previous setting has not been
lost, and the logging of this channel’s data can be restored by pressing
the set button again with the transmitter not connected. It is always
preferable to deselect the channel with the transmitter connected, but
this is method is convenient where is impractical to retrieve the
transmitter. It is also useful for logging different subsets of the installed
transmitters.
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14.3.4 Metering
The RX250AL Squirrel has two methods of displaying values in the
Meter function:
1. If the transmitter is connected directly to the RX250AL, the current
value for each channel will be displayed.
2. If the transmitter is not connected, then the display will show the last
received value for that channel. It is possible that in this situation
there may not have been any received values from the transmitter.
The RX250AL would then display the following:
M E T E R
c h
1
- - - ° C
This simply indicates that there have not yet been any readings from
that channel received by the RX250AL. This will be replaced with a
value as soon as the RX250AL receives one.
If a transmitter is plugged in that hasn’t (yet) been set up in the Channel
Set-up function of the RX250AL, the display will show the following:
M E T E R
u n k n o w n
T X
In order to meter this transmitter, it would be necessary to assign it to a
channel in the Channel Set-up function.
14.3.5 TX Battery and Reliability
The TX battery and Reliability function can be found after the Channel
Setup function. As with some of the other functions, its behaviour
depends on whether a transmitter is connected to the RX250AL with the
programming lead.
If no transmitter is connected, the RX250AL will display a summary of
each transmitter when the select button is pressed:
T X - 1 2 3 4
5 7 %
9 3 % r e l
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Pressing the select button again will show a different transmitter
(assuming more than one has been set-up for the RX250AL). The order
in which the transmitters are shown in this function reflects the
sequence in which they were configured on the RX250AL.
If the RX250AL has not yet received a battery reading from any
particular transmitter, then the display will show a series of dashes
instead of the battery voltage:
T X - 1 2 3 4 0
- - - 9 3 % r e l
As soon as the RX250AL receives information on the level of the
battery, it will be displayed here.
The reliability figure on the right-hand side of the display is there to give
an idea of how well the transmitted data packets are being received by
the RX250AL. Note that before logging starts the reliability value is
unavailable, so it is replaced with a series of dashes:
T X - 1 2 3 4 0
5 7 %
- - - % r e l
The reliability value is expressed as a percentage of how many
transmissions were successful. It is calculated by comparing the number
of packets successfully received by the RX250AL during the last logging
interval with the number of packets expected, based on the
transmission interval of the transmitter. This figure is then subject to a
rolling average, so it is only after a few record intervals that the f igure is
representative of the reception reliability of the transmitter. A typical
system, where the transmitters are well within the operating range, and
where there aren’t a large number of transmitters on short intervals,
should show reliability figures in the high nineties.
Should the RX250AL report a lower value for any transmitter, then this
is an indication that the transmitter should be moved to a different
location to improve reception at the RX250AL. Sometimes a small
move will improve the reception greatly. A reliability figure of 95%
should be aimed for.
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14.3.6 Deleting Transmitters
The Channel Setup function is designed to allow the selection and
deselection of transmitter channels. Wherever possible, all channel
configuration should be done in Channel Setup. However, there are
situations where a transmitter needs to be removed from the RX250AL
channel configuration without the transmitter being available to properly
deselect it using the Channel Setup function. This can be achieved by
selecting the transmitter in the TX Battery and Reliability function, and
then pressing the set button. The display briefly shows the following:
T X - 1 2 3 4 0
H O L D T O D E L E T E
If the set button is held down the RX250 briefly displays the following,
and deletes all record of it from its configuration:
T X - 1 2 3 4 0
D E L E T I N G
S Q
Finally, the display ends up with ‘DELETED’ on the bottom line.
Accessing the Channel Setup function will confirm that all channels that
were using this transmitter are now ‘not configured’. Note that the
transmitter is not aware of this, and will still be transmitting. This not
only wastes battery power in the transmitter, but also leaves its
broadcasts still occasionally colliding with those from other transmitters.
It is for this reason that channel deselection is best done using the
Channel Setup function.
In the above screen shot, the display shows ‘DELETING SQ’. This
indicates that the RX250AL is only deleting the settings in the RX250 for
this transmitter. This behaviour is different when a transmitter is
plugged into the RX250AL with the programming lead. In this instance,
the TX Battery and Reliability function will only show information about
the connected transmitter, and the information it shows is a little
different:
T X - 1 2 3 4 0
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5 7 %
2 C H
Whether or not the connected transmitter is configured for use with the
RX250AL, it will show the above details. The battery capacity is shown
as before, but here it is taken straight from the transmitter. On the other
side of the display, (where the reliability was previously displayed) is
shown the number of channels the transmitter is configured to transmit.
These may or may not have been set up on this RX250AL. The select
button does nothing in this situation, as the RX250AL will only report on
the connected transmitter. The set button still does the same job, but
with a slightly different angle. If the transmitter has come from another
system (i.e. has not been set up on this RX250AL), pressing and
holding the set button will delete all the channel assignments within the
transmitter:
T X - 1 2 3 4 0
D E L E T I N G
T X
Note that the display shows that the RX250AL is deleting the
configuration of the transmitter this time. If the connected transmitter is
configured to work with the RX250AL, the display will show the
following:
T X - 1 2 3 4 0
D E L E T I N G
S Q + T X
This indicates that the transmitter’s configuration is being deleted and
the associated channel assignments in the RX250AL are being deleted.
In either situation, the state of the transmitter is confirmed afterwards:
T X - 1 2 3 4 0
8 . 3
V
0 C H
The number of channels used in the transmitter is now reported to be
zero.
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14.3.7 Calibration
Humidity sensors only can be calibrated in software by connecting the
transmitter to the RX250AL with the LC-TX programming lead. The
wired connection is required for two reasons. Firstly, the value from the
sensor is sent to the RX250AL immediately, so it can be clearly seen
when a sensor value has settled. Secondly, the calibration is stored in
the transmitter, rather the in the RX250AL, so the calibration of the
sensor can be done away from the system, if required.
The Calibration function can perform either a one or two point
calibration. The value of both points can be changed to match the
calibrator.
In order to enter the Calibration function, a transmitter must be
connected, and the select button pressed:
C A L I B R A T I O N
If select is pressed without a transmitter connected, the RX250AL will
display a message to instruct the user to do so:
C A L I B R A T I O N
c o n n e c t
T X
Once a transmitter is attached to the RX250AL with the programming
lead, pressing the select button puts the RX250AL into the calibration
mode.
C A L I B R A T E
1 3 . 0 %
S E N S O R
2 1 . 6 %
Before performing the calibration though, it is necessary to set the
calibration points. Pressing the select button twice more allows you to
set the lower calibration point:
C A L
P O I N T
1 3 . 0 %
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1
Pressing and holding the set button allows subsequent presses to
increment the value in 0.5% increments up to 60.0%. This value should
be set to match the calibrator that will be used. A single point calibration
will only use Cal Point 1, which is the zero point. Pressing the select
button moves the display onto Cal Point 2, which is the span, and is
only used for two-point calibrations. This is adjusted in same way as the
first, but the range available is 50.0% to 100.0%. Cal Point 1 should
always be lower than Cal Point 2 for two-point calibrations.
14.3.8 Calibrating the Sensors
Pressing the select button from the Cal Point 2 setup puts the RX250AL
back to the first calibration page. This calibrates the lower selected point
on the sensor. The display shows Cal Point 1 and the current v alue from
the sensor:
C A L I B R A T E
2 2 . 0 %
S E N S O R
2 1 . 6 %
The sensor should be placed in the calibration device. Once the reading
has stabilised, the set button should be pressed and held to set the
sensor to read the value of Cal Point 1 for the present input. If the
calibration is too far out, the RX250AL displays ‘CAN’T SET’. This may
be caused by setting the wrong value for the Cal Point, by putting the
sensor in the wrong solution, or it could mean that the sensor element
needs replacing. This can be done by the user, after which the
calibration must performed again. A two-point calibration can be
performed by repeating the above procedure for Cal Point 2. Pressing
select moves the RX250AL on to the second calibration point.
14.3.9 RX250AL LED Indicators
There are two LED indicators on the rear of the RX250AL. The green
LED is marked ‘run/rx’ and shows the reception status. While the logger
is in a state to receive data from the transmitters, the green LED will
flash about once a second. Occasionally, it will stay on for about a
second. This indicates a new data packet has just been received. If the
LED is constantly off, the RX250AL has switched off the receiver. This
74
typically indicates that the RX250AL has lost external power and its
batteries are nearly flat (see section below on the RX250AL power
supply).
The red LED is marked ‘check system’. It indicates a system problem
and can be ON due to a number of conditions. The user should
investigate. These conditions are:
1. One (or more) of the transmitter’s batteries has dropped below 10%
2. The RX250AL has not received a data packet from one (or more) of
the transmitters during the last record interval.
The source of both of these problems can be determined with the TX
Battery and Reliability function. As soon as all the problems have been
alleviated, the LED will switch off again.
The second problem could be due to a transmitter being moved or
damaged, or by a transmitter being out of range.
If the battery voltage in a transmitter is low, the battery will need to be
replaced. However, preventative action can still be taken before the
data being logged will start being affected. Once the battery voltage
falls to 0% the transmission will stop to prevent the RX250AL storing
inaccurate readings. The battery can be replaced without any need to
reconfigure the transmitter, as the settings are stored in its non-volatile
memory. The red LED will be switched off once the RX250AL receives
a data packet containing a valid battery reading.
If both red and green LED flash simultaneously this indicates that the
logger is operating in an invalid mode. Both LEDs will revert to normal
operation once logging recommences. The RX250AL will normally selfrecover. Both LEDs flashing simultaneously can indicate a radio fault, in
which case Eltek should be contacted.
14.3.10 Transmitter LED Indicator (top panel)
A red LED on the transmitter flashes for the following reasons.
A brief blink every 8 secon ds indicates that it is operating normally,
but is not configured to transmit anything. It is put into this state from a
‘cold start’ (i.e. from the factory). It will stay in this mode until it is set up
with the RX250AL or using Darca Plus software.
A longer blink on each transmission. Once configured indicates
normal operation.
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A brief blink every secon d indicates a successful connection has been
made to the PC and Darca Plus. The LED will revert to the configured
status after 3 seconds when the communications is disconnected.
A double blink every 8 seconds indicates a fault. The transmitter will
need attention.
A concealed test switch, accessed using e.g. a paper clip, is located
behind a small hole in the transmitter rear panel. This is a very useful
feature when setting up the system and when conducting a radio survey.
·
Holding the switch down will cause the transmitter to transmitter
approximately every second until released.
·
A brief press will cause a transmission very 5 seconds (albeit at
a random point in time in the 5 second slot) for about 20
transmissions. It will revert to normal operation after.
14.3.11 RX250AL Power Supply
The RX250AL is supplied with six Ni Mh rechargeable batteries installed
in the battery compartment. These are charged from the 12V DC input
jack. The batteries can keep the RX250AL powered for up to 24 hours
(if fully charged) in the ev ent of a power failure.
The RX250AL will inhibit the receiver prior to total battery exhaustion, in
this event, the RX250AL continues logging at the specified interval, but
stores dummy values. While powered down, the ‘run/rx’ LED will stop
flashing.
When AC power returns the logger automatically enables the receiver
and starts to recharge the battery and can take up to 3 days to fully
recharge. The battery page of the STAT function indicates the number
of hours the receiver will keep running in the event of AC supply failure.
If discharged it may take more than 1 day of recharging before the
hours displayed in this function rises above 0. If the RX250AL is not
logging, the receiver circuitry will turn off within ten minutes after the
external power is removed.
WARNING:
UNDER
NO
CIRCUMSTANCES
SHOULD
NON
RECHARGEABLE BATTERIES BE INSTALLED IN THE RX250AL. DOING
76
SO MAY CAUSE THEM TO LEAK OR EXPLODE. FAILURE TO OBSERVE
THIS WARNING WILL INVALIDATE THE WARRANTY.
The battery should last for many years. However annual testing is
recommended, once the system is more than 3 years old, by unplugging
the mains adapter while the RX250AL is logging and letting the unit run
for a few hours. If the receiver switches off sooner than indicated by the
STAT function, then replacement rechargeable batteries should be
obtained from Eltek Ltd.
14.3.12 Transmitter Battery Pack
When changing the transmitter battery always replace with a set of new
AA alkaline batteries. The transmitter LED will flash when it restarts
correctly. If this does not happen remove the battery, wait 10 seconds
and reconnect it.
14.3.13 Improving Reception
Radio waves travel best in open unobstructed spaces. Aerials work best
high up in open spaces. Unfortunately, it is rarely possible to have both
of these criteria met! but these two statements should be kept in mind
when installing the radio system. This will lead to the best performance
of the system that can be obtained in a given situation. Note that metal
objects and thick walls significantly attenuate radio signals. Reinforced
concrete is a real signal killer as it can act like a metal screen.
If a nearby source of interference contains frequency components in the
band of the system, then the receiver will obviously be desensitised.
This is especially true if the interference is stronger than the signal from
a distant transmitter. Typical sources of interference are mobile phones,
walkie-talkie type radios, computer equipment (especially older
equipment) and anything with a radio transmitter in it, e.g. the
components of a wireless security system.
14.3.14 Locating the Transmitters
For best range place the transmitter as high up as possible. Keep away
from damp or metal clad walls, metal objects, cabling, pipes, etc. Also
bear in mind that the fewer obstacles in the path to the receiver will give
the greater range and reliability of the system.
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14.3.15 Locating the RX250
The RX250AL is a single unit that combines both receiver and data
logger. Locate the RX250AL central to the transmitters and clear of
sources of radio interference. See 14.3.3 Improving reception above.
Where range is not a problem the built in antenna supplied should be
used and provides a very compact installation. Range can be very
significantly improved using the optional dipole antenna. This should be
mounted as high as possible and away from sources of interference.
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15. Darca
15.1 Introduction
Darca is a 32-bit Windows program for setting up, downloading, and
translating data from 1000 Series and other compatible Squirrels. It has
many features designed to speed up and assist in all aspects of Squirrel
management:
·
·
·
·
·
·
·
·
·
·
·
·
·
Modern interface makes the advanced features of the Squirrel
easily accessible and configurable.
Multithreaded communications routine improves responsiveness.
Multiple channels can be edited simultaneously.
Downloading times have been substantially reduced on all new
Squirrels.
Squirrels can be contacted directly or via modem.
Phone list makes accessing a number of Squirrels straightforward.
Setups can be saved to disk and uploaded to Squirrels.
Squirrel settings can be quickly changed off-line, and then uploaded
efficiently at a later date.
Automated contacts can set up and download Squirrels on demand
or from separate ‘Shed’ scheduling utility (included).
Channels can be renamed for easier identification when metering.
Alarms can be set up and metered - even on Squirrels without
alarms.
Data can be graphed using powerful graphing tools.
15.1.1 Online Help
The majority of the documentation for Darca is kept online in the Help
system. For more information on any item within the program, click
Help, or press the F1 key. The Help file also contains a detailed tutorial.
15.1.2 System Requirements
System requirements are:
·
·
PC running Windows 98,SE,ME,XP,2000 and NT4.
CD-Rom disk drive (for installation).
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·
·
·
·
·
·
·
8Mb RAM.
4Mb free hard disk space for program.
VGA (or better) display.
One unused serial port.
Additional hard disk space for data.
Compatible modem, (for dialling up remote RX250, if required)
LC68 cable (RX250 to PC serial cable)
15.1.3 Installation
1. Insert CD in CDROM drive.
2. From the Start Menu, choose Run…
3. Type x:\setup (where x is CDROM drive) and press return.
4. Follow the on-screen instructions. Note: The installation program
will create a folder called ‘Darca’ within the folder you specify.
5. To run Darca, select the Darca icon from the Programs Menu.
6. To launch Shed automatically every time Windows is started, create
a shortcut to Shed in the StartUp group.
Darca creates two sub-folders within its main program folder:
· ‘Setup’ – which is used for storing Squirrel setup files.
· ‘Squirrels’ – which keeps a database of information about every
Squirrel contacted in order to speed up contact time.
These sub-folders are for the storage of Squirrel settings and data, and
may be moved to a different location - provided that the relevant details
are updated in the Folders tab of the Settings|Preferences dialog box.
15.2 Overview
Darca stands for Downloading and Remote Control Application. It is
designed to communicate with Eltek, the main functions are;1. Downloading data
2. Exporting data into a spreadsheet or Graphing data
3. Remote configuration of settings and channel set-up.
This may be achieved either through a direct RS232 cable, or via
modems connected to the public telephone system (or a private
exchange).
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15.2.1 Darca Plus and Darca Lite
Darca is available in two versions: Darca Plus and Darca Lite. These
two versions are exactly the same except that Darca Plus contains
graphing tools and modem contact. An upgrade (‘Darca Up’) is available
to upgrade from Darca Lite to Darca Plus.
Note: GenII Radio Data Logging System is designed for use with Darca
Plus only.
The documentation that comes with Darca, such as the online help, will
refer to the features available in Darca Plus as well as the standard
features common to both versions. These extra features should be
ignored by users of Darca Lite.
15.3 The Main Window
The Main Window is the first window that appears when Darca is
launched. The top of the Main Window carries a menu bar through
which all of the program’s functions can be accessed. The Status Bar at
the bottom displays information about the status of communication
between Darca and the Squirrel. Between the Menu Bar and the Status
Bar is the Control Panel. The buttons that appear on here depend upon
the current connection status. When Darca is first started, the
Control Panel shows the buttons listed below:
Export Data - Converts a Squirrel Data file (.DAT) into a text file
suitable for importing into spreadsheet programs.
View Graph – Displays a graph of a DAT file. (Darca Plus)
View Export – Displays exported data in a table. (Darca Lite)
Preferences - Makes changes to the way Darca operates.
Contact Wizard - Goes through two steps of establishing contact
with the Squirrel, allowing configuration of the way the Squirrel
will be contacted.
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15.4 The Contact Wizard
The Contact Wizard provides an easy way to select the method that
Darca will use to contact the Squirrel. In the first stage of the Wizard,
the type of connection must be chosen from Manual, Automated or
Offline. Choosing ‘Offline’ in step 1 of the Contact Wizard will ask for a
Squirrel name and then start a new Offline Setup based on this Squirrel.
If the choice made is either Manual or Automated, the Contact Wizard
moves to step 2, where either a Direct or a Modem connection can be
selected. A Direct connection will simply contact the Squirrel via the
LC68 cable, whereas a Modem connection requires a phone number
with which to dial the modem. Step 2 of the Contact Wizard also asks
whether the Squirrel is Networked, and allows configuration of the
Communications settings through the ‘Configure Communications’
button.
An Automated contact is an advanced method for automating the
process of contacting one or more Squirrels on regular basis. A contact
started in this way cannot be interacted with.
15.5 The Contact Window
The Contact Window appears once a Squirrel has been contacted.
From here the settings in the Squirrel can be changed online, logging
can be started and stopped, runs can be download from the Squirrel and
the Squirrel’s memory can be cleared. The Meter Channels
window can also be opened.
The following buttons appear on the Contact Window:
Download Runs – Displays the Download dialog box.
Meter Channels - Displays the current input of all the selected
channels in diagrammatic or graph f orm (Darca Plus only).
Squirrel Settings - Configures various aspects of the Squirrel
using Darca.
Channel Setup – Configures the channels on the Squirrel.
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15.6 The Status Bar
The Status Bar at the bottom of the window contains four areas that
indicate the status of the connection between the Squirrel and Darca:
·
·
·
·
The left-hand box simply shows whether or not a connection has
been established.
The next box shows the current state of the communications
through the selected serial port.
The third box is the state of the Squirrel, either asleep or awake.
Darca must wake the Squirrel before communications can start.
The right hand box shows ‘Retries’ followed by two numbers. The
first number is the number of times Darca has failed to wake up the
Squirrel. The second number is the number of times Darca has not
had a response from a transmitted command.
15.7 Menus
The menus provide access to all of the functions and options of Darca.
Some of the menu items are just alternative ways of getting to the same
functions that the buttons provide.
15.7.1 File Menu
The File Menu contains the options for all the file-based operations in
Darca. It also contains the option to quit the program.
Open Setup
Allows Darca Squirrel Setup files (*.dss) to be loaded from disk. If this
option is selected when Darca is in contact with a Squirrel, then the
selected Squirrel setup is sent to the Squirrel. Note that the setup file
can only be sent to the same model of Squirrel for which it was created.
This option is also available when Darca is not connected to a Squirrel.
In this context, Darca will open the file in offline mode. This allows the
settings within the file to be changed without the need to connect a
Squirrel. See ‘offline contact’ in the online help for more information.
Close Setup
Closes an open Squirrel Setup File. If the file has not been saved, a
83
prompt appears to confirm the action.
View Export
Enables the viewing of exported Squirrel data in text or tabular form.
View Graph
Displays a graph of a Squirrel data file together with summary
information.
Save Setup
Stores the current Squirrel setup to disk. If the current setup has not yet
been named, the Save Setup As dialog appears.
Save Setup As
Stores the current Squirrel setup to disk after prompting for a filename.
Download
Only available during contact with a Squirrel, this option initiates the
transfer of recorded data from the Squirrel to the computer.
Export
Once data has been downloaded from the Squirrel, it may need to be
processed into a form that can be read by a spreadsheet application.
Choosing this option brings up a dialog from which the data file can be
selected. Darca then processes the data in accordance with the current
Export Settings and writes it into a new file. Note that Darca can be
configured to automatically export the data immediately after a
download.
Memory Card Utils
Some special Squirrels use PC Memory (SRAM) Cards to store data.
These utilities enable preparation and management of the card and its
data.
Exit
Quits the program.
15.7.2 Contact Menu
The Contact Menu contains the available options for contacting
Squirrels in Darca. It also contains the option to subsequently
disconnect from the Squirrel.
84
Direct
Initiates contact with a Squirrel connected to the computer’s serial port.
The correct serial port must be selected and a compatible baud rate
must first be chosen from the Communications option in the Settings
menu.
Modem
Jumps to the 2nd page of the Contact Wizard, and selects the Modem
option. This page of the wizard allows a phone number to be entered.
Once this is done, the Next>> button starts the modem dialling, and
initiates the contact. It is important to configure the Squirrel modem
correctly; for more information on how to do this, refer to Darca’s online
help.
Automated
To minimise connection time, and to allow execution of a predeterm ined
set of actions on a Squirrel, Darca can be configured to carry out
contacts automatically. The required tasks can be specified in the
Preferences option on the Settings menu.
Contact Wizard
See The Main W indow for more information.
Disconnect
Stops all communication between Darca and the Squirrel, and returns
Darca to the Contact Window. In offline contact this option closes the
current Squirrel Setup File and returns Darca to the Mai n Window.
15.7.3 Settings Menu
The Settings Menu contains options that configure Darca. Options for
changing the Squirrel’s settings are found in the Squirrel Menu.
Preferences
Displays a multi-tabbed dialog box from which most of Darca’s settings
can be changed. Most of these settings are stored when Darca is exited.
Communication
All of the communication settings for Darca are displayed in the
communications dialog box. These settings are stored when Darca is
exited. Settings for the modem can also be changed from here, though
any changes in these will not be retained when the program is exited.
85
Phone List
A list of descriptions, phone numbers and
be stored in the phone list. The Tool Bar
window has buttons to enable entries to be
Clicking on one of the headings will sort
column.
Squirrel serial numbers can
at the top of the phone list
added, edited and remov ed.
the entries by the selected
15.7.4 Squirrel Menu
The Squirrel Menu only appears when Darca is in contact with a
Squirrel. It contains the all the options for changing the settings of the
Squirrel.
Refresh Status
Periodically, the Squirrel Status window is updated with the current
status of the Squirrel. This option forces Darca to update this window
immediately and re-open it if it has been closed.
Log
The Squirrel’s current logging state is shown by this menu item. A check
mark next to this option indicates that the Squirrel is currently logging.
Selecting this option will change the logging state by either starting or
stopping the Squirrel logging. The logging state of the Squirrel can also
be changed by the central control of the Contact Window.
Clear Memory
This option is not available when the Squirrel is logging. When it is, this
option will clear all the readings from the Squirrel’s memory. The
memory can also be cleared using the central control of the Contact
Window.
Settings
All of the Squirrel’s settings (with the exception of the channel setup)
are controlled from a single tabbed dialog box, which can be accessed
by selecting this option. If the Squirrel is not reset, there will be some
settings that cannot be changed.
15.7.5 View Menu
The items in the View Menu are all for showing non-dialog windows for
either displaying Squirrel information or changing channel settings. Any
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or all of the windows opened from the View Menu may be open
simultaneously. Reselecting an already open window will bring that
window to the front.
Squirrel Status
This window is automatically shown when contact is established. It is
recommended that this window is left open permanently, and moved to
a convenient location on the screen. It can then be quickly referred to at
any time for the current status of the Squirrel. This window will be
automatically opened to confirm significant changes to the Squirrel
settings (e.g. whenever the Squirrel is set to start logging).
Meter
The Meter Window shows all the current input states of all the currently
enabled channels. The interval at which it is updated can be changed in
the Settings|Preferences dialog box. The appearance of the meters can
be controlled from the context menu, which is brought up by right
clicking anywhere on the Meter W indow.
Channel Setup
A spreadsheet-style grid clearly shows each channel and its
corresponding settings. Ranges, EU Settings, and Alarms can be
reconfigured for individual or multiple channels from the Channel Setup
Window. A context menu (which can be brought up by right clicking on
the Channel Setup Window) shows the available options for the
currently selected channel(s). Selecting Edit Channel brings up a tabbed
dialog box from which all of the changes are made.
Transmitter Status
This feature is for use with Eltek Telemetry Squirrels only. It displays
information about the transmitters connected to the Squi rrel.
15.7.6 Help Menu
The Help Menu contains all of the normal help menu items for the
program. A comprehensive on-line help system (including a tutorial
section) gives all the information needed to get the most out of Darca.
15.8 The Graph Window
The Graph Window may appear in two forms – the Offline Graph
Window or the Online Graph Window. As well as displaying the graph
87
and legend, both windows contain a toolbar that provides features to
manipulate the graph:
15.8.1 The Offline Graph Toolbar
Graph Appearance
This window allows general graph settings such as colour, gridlines, 3D
graphing options and plot type to be configured. These settings are
stored and are used whenever a new graph is opened.
Chans / Axes
This window provides control over the ranges of the graph axes and the
selection of which channels are to be plotted on the graph and their
assigned colour and axis.
Cursor
The graph cursor displays the exact data values at a point on the graph
when it is clicked on.
Thresholds
Graph thresholds allow the plotting of threshold limits alongside the
channels’ data on the graph.
Summary
The summary window shows information about the Squirrel used to
create the data, the data itself, and statistics calculated from the data.
Note
In order to identify meaningful points on the graph, notes may be drawn
onto the graph which consist of a line at the relevant point together with
a text label.
15.8.2 The Online Graph Toolbar
The online graph toolbar contains many of the same tools as the offline
graph toolbar. However, there are two additional ones:
Save
This saves all the data plotted on the online graph into a Squirrel DAT
file which may be viewed later once contact is finished.
Pause
This pauses the flow of data onto the graph and stops it scrolling until
pausing is finished, whereupon data received during the paused period
88
will be plotted onto the graph.
15.9 Automated Contact with a Squirrel
Darca’s Automated Contact feature allows you to specify a number of
tasks which you wish to be performed during a contact with a Squirrel.
This is particularly useful if you have a number of Squirrels which all
require a set series of operations to be performed during contact, or if
you are using a modem to connect to your Squirrel and wish to
minimise the length of the call. Four tasks may be performed on a
Squirrel during automated contact: Download All Runs (the most recent
run is always downloaded), Clear And Restart, Send Setup File and
Update Time And Date. The Send Setup File option allows you to
configure the Squirrel exactly as you require using a previously saved
setup.
15.9.1 Scheduling Automated Contacts using Shed
Shed allows you to perform scheduled automated contacts by launching
Darca at a specified time. It is possible to specify the exact type of
automated contact using command-line parameters, more details of
which can be found in Darca’s online help. You may schedule repeated
automated contacts with a Squirrel by using the ‘frequency’ setting in
Shed.
89
16. Safety and operating conditions
16.1 Operator safety
TO PROTECT AGAINST SHOCK HAZARDS TO OPERATORS,
datalogger inputs and outputs should not be connected to voltages of
more than 25V DC or RMS AC with respect to earth (ground) unless the
datalogger is inside a protected enclosure.
16.2 Squirrel safety
The following inputs are protected up to specific voltages:
Input type
Analogue
External trigger
Pulse
Event
External Power Supply
Maximum voltage
25
6
6
5 (can be increased to 6V, see 5.9)
14
DO NOT APPLY LARGER VOLTAGES OR THE SQUIRREL COULD
BE DAMAGED.
16.3 Errors caused by ground connections
For voltage and current inputs only. While a reading is being taken,
both input terminals are connected through a 1MW resistor network to
the datalogger ground. At all other times, both terminals are floating.
Datalogger ground may become connected to mains earth (ground), e.g
via a mains connected computer or an earthed power supply. If this
happens, measuring errors will be caused if either input terminal is at a
voltage of more than ± 15V with respect to datalogger ground. All other
inputs and outputs have one terminal permanently connected to the
datalogger ground.
16.4 Operating condit ions
The datalogger can be used at temperatures between -30 and +65°C
and with relative humidity up to 95% (non-condensing). At ambient
temperatures below -5°C the display becomes progressively slower to
change, and may fade at temperatures below -30°C. However, this will
90
not affect any other functions of the datalogger; readings will be
retained in the memory and logging will continue.
If a datalogger is used in a low ambient temperature, internal
condensation can occur if it is brought into a warmer environment. The
datalogger should be placed in a sealed container (a plastic bag
provides a cost-effective solution). The container should remain sealed
until the datalogger has warmed up to room temperature.
16.5 Protection against memory loss
The memory, which stores the data and datalogger settings, is protected
by a Lithium coin cell (3V Panasonic BR2032). This battery is only used
if the voltage of the main batteries is below the operating threshold. If
there are no main batteries connected, the Lithium coin cell will protect
the stored data for approximately 2 years.
The condition of the Lithium coin cell may be checked in the STAT
battery function (see 4.10.1). If ‘Li’ is displayed in the top right hand
corner of the display, then the Lithium coin cell must be replaced.
16.6 Changing batteries
It is important that one of the following procedures is used to change the
batteries, otherwise memory and logger settings may be lost: Stop logging, remove the batteries and wait at least 2 minutes before
fitting new batteries as a complete new set of the same type.
Alternatively, connect an external power supply for uninterrupted
logging, and then change the batteries.
It is good practice to ensure that the logger is not left for long periods
without the main batteries as this will drain the Lithium coin cell, which
will need to be replaced.
16.7 Resetting the datalogger
The 1000 Series Squirrel datalogger has a ‘watchdog’ facility that
automatically resets the datalogger in the unlikely event of a system
failure. If failure occurs, the watchdog will reset the datalogger and stop
logging (if logging is in progress). Stored data can then be downloaded.
Should the datalogger ever hang up completely, it must be reset
manually by pressing the reset button. This black reset button is located
to the left of and below the opened battery compartment and is
accessible through the aperture where the catch of the battery lid
engages; it should be depressed using a blunt insulated probe. If this
91
fails, remove all power to it and leave it for 10 minutes before
reconnecting, and then press the reset button.
16.8 Changing fuses
There are three places where fuses are used to protect the circuits of
the datalogger. These are the external power supply input, the sensor
supply outputs and each current channel input. If an external supply is
connected and cannot be measured as described in section 4.10.2 then
the logger power supply fuse may be faulty. If none of the sensor supply
outputs is working then the sensor supply output fuse may be faulty. If a
current channel does not measure correctly then its fuse should be
checked by measuring the resistance between the c and - terminals of
the input. This should be 10 ohms.
Fuses should only be replaced by a competent person. Any
damage caused to the instrument while attempting to replace a
fuse yourself cannot be covered by the guarantee. You should
return the Squirrel to your supplier who will be able to replace it
for you. If you are comfortable with this, and feel you are
competent enough, proceed as follows:
The four case screws must be removed (one is hidden under a battery
contact in the battery box). The top of the case can then be lifted off.
The 1A fuse on the board with the external power connector is for the
external power input. The channel input fuses (250mA) are by the
connector for each current input. The sensor supply fuse (250mA) is on
the far right of one of the input boards. All fuses are the round plug-in
types.
16.9 Sensor supply voltage
The Squirrel is shipped with the sensor supply voltage selector jumpers
all set to 9V. If 5V ±0.1% is required to power a sensor, then an internal
jumper needs to be moved. For more information on the sensor supply,
see section 4.10.4.
The method for remov ing the top of the case is detailed above, in
section 16.8, and the same cautions apply. All boards down to the
one that needs the adjustment will need to be remov ed. The sensor
power jumpers should always cover two of the three pins, and are
usually situated close the input connectors. The appropriate jumper
needs to be moved to connect the middle pin to the other edge pin. The
92
boards must then be reassembled in the correct order, taking great care
to align all of the pins on the internal connectors.
93
17. Technical data
17.1 Inputs, ranges and resolutions
Input type
Thermistor temperature (U)
Best resolution
Worse resolution
Available ranges
-50 to 150°C
-58 to 302°F
-5 to 75°C
-25 to 5°C & 75 to 100°C
-40 to -25°C & 100 to 125°C
-50 to -40°C & 125 to 150°C
Resolution
See below
0.05°C
0.1°C
0.2°C
0.4°C
Thermocouple temperature (T)
Impedance: 100kW
-200 to 200°C
-200 to 350°C
-328 to 392°F
-148 to 662°F
0.1°C
0.2°C
Thermocouple temperature (K)
Impedance: 100kW
-200 to 200°C
-200 to 450°C
-200 to 1200°C
-328 to 392°F
-328 to 842°F
-328 to 2192°F
0.1°C
0.2°C
0.5°C
PT100 temperature (P3/P4)
-200 to 100°C
-200 to 400°C
-200 to 600°C
-328 to 212°F
-328 to 752°F
-328 to 1112°F
0.1°C
0.2°C
0.25°C
DC voltage
0 to 50mV
0 to 100mV
0 to 200mV
0 to 500mV
0 to 1V
0 to 2V
0 to 5V
0 to 10V
0 to 20V
-25 to 25mV
-50 to 50mV
-100 to 100mV
-250 to 250mV
-500 to 500mV
-1 to 1V
-2.5 to 2.5V
-5 to 5V
-10 to 10V
50µV
50µV
50µV
0.5mV
0.5mV
0.5mV
5mV
5mV
5mV
Impedance: 1MW
DC current
Impedance: 10W
4 to 20mA (as 0 to 100%)
0 to 20mA
0.05%
10µA
Impedance: 1MW
0 to 65,000
0 to 650,000
1
10
Impedance: 1MW
0 to 255
00000000 to 11111111
Pulse count
Digital
State
94
17.2 Specification
s
h
l
Accuracy
(at 20°C)
Environment
Power supplies
Battery life
Clock accuracy
Physical
details
Interface
RS232 Output
Sensor power
Digital inputs
d
Voltage
±0.1% of reading ±0.1% of span
Temperature
±0.2% of reading ±0.1% of span
Ambient temperature -30 to 65°C. Humidity up to 95% (noncondensing).
Internal: six size AA manganese-alkaline batteries (such as Duracell
MN1500).
External: 9-14V DC at 100mA.
At least 6 months with 8 channels recording every 5 minutes.
1 second/day at 20°C.
Dimensions: (l) 180 mm x (h) 120 mm x (s) 60 mm or (d) 85 mm.
Weight (including batteries): 1 kg.
Material: ABS - blue suede finish.
RS232C at these baud rates: 300, 600, 1200, 2400, 4800, 9600.
6 pin female mini-DIN socket.
0-60 seconds, 50mA maximum total load.
Pulse count, event, external trigger. Impedance: 1M W
Start/low
0 to 0.5V DC or contacts closed.
Stop/high
4 to 6V DC or contacts open.
95
18. Connections
18.1 Signal connector
The connector marked ‘signal’ is a 15 way male D connector. It is both a
digital/event input, and the external trigger input. The connections are
as follows:
15 way male D
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
Description
Event bit 8 (MSB)
Event bit 7
Event bit 6
Event bit 5
Event bit 4
Event bit 3
Event bit 2
Event bit 1 (LSB)
Digital ground
Alarm output
Relay contact 1
Relay contact 2
Digital ground
External trigger input
Spare input
15 14 13 12 11 10 9
8 7 6 5 4 3 2 1
Solder view of female
15 way D connector
18.2 Output connector
The connector marked ‘output’ is for communications between the
Squirrel and a computer or modem for remote control and for data
transfer. The connections are as follows:
6 way male mini
DIN connector
1
2
3
4
5
6
Description
Reserved (S2 in)
Serial output
Digital ground
+9V output
Reserved (S2out)
Serial input
96
1
2
3
4
5
6
Solder view of male 6 pin
mini DIN connector
LC69 connection details
For connecting a 1000 Series Squirrel to a modem, the cable LC69 is
required:
25 way male D
connector
7
2
3
4, 5 & 20
Description
Ground
Data from Squirrel to modem
Data from modem to Squirrel
Link A
6 way male mini
DIN connector
3
2
6
18.2.1 LC68 connection details
For direct connection to a 1000 Series Squirrel, the cable LC68 is used:
9 way female D
connector
5
3
2
4&6
7&8
Description
Ground
Data from computer to Squirrel
Data from Squirrel to computer
Link A
Link B
6 way male mini
DIN connector
3
6
2
18.2.2 Network cable connection details
As for LC68, but all the 1000 series Squirrels are connected in parallel:
PC
9 way female D
connector
5
3
2
4&6
7&8
Squirrel 1
6 way male mini
DIN connector
3
6
2
Squirrel 2
6 way male mini
DIN connector
3
6
2
97
Repeat
For all
Loggers
Last Squirrel
6 way male mini
DIN connector
3
6
2
19. Communications leads RX250AL and SC250
GenII receiver/loggers provide 2 x serial ports on the “Output” connector.
The assignm ent of pins is common. Port specifications are as follows;
Port1(P1) – provides full communications with the logger. Maximum comms
speed is 38.4Kbps.
Port 2(P2) – provides f ull communications with t he logger with com ms speed at
9,600Baud plus the output f or text messaging.
The pin assignm ents are;
mini DIN
Description
1
Serial port # 2 - input
2
Serial port # 1 - output
3
Digital ground
4
+12V nominal from external power
connected to the receiver logger.
5
6
Serial # 2 - output
Serial # 1 - input
1
2
3
4
5
6
Solder view of male 6 pin
mini DIN connector
Use the table below to specif y the correct lead or lead combinations;
RX250AL, RX250ALD and SC250
Lead type
Ethernet
GSMSQ for
PC
Notes
using
Text or remote Serial port
Moxa
access
D311
LC68
P1
LC68 supplied with
logger
LC68
P1
LC68+LCxx +
LC-DP
GSM-mdmcom2
LC68+GSMmdmcom2+LC-DP
LC68+GSMmdmcom2+LC-DP
P1
P2
P2
P2
P1
P1
LC68 connects to
P1 and LCxx to P2
Specify GSM-mdmcom2 for Wavecom
Supreme
modem
and GSM-mdm-2X
for Extend modem.
P2
Splitter is the lead type LC-DP and can be ordered as a spare from
Eltek.
98
Lead type LCxx is special – refer to Eltek or an Eltek distributor.
99
Declaration of Conformity
Manufacturer
Eltek Ltd
Haslingfield
Cambridge CB23 1LL
UK
Description of Equipment
1000 Series Squirrel Meter/Logger
GEN2 transmi tters
I confirm that this instrument conforms to the requirements of the EMC
Directive 89/336/EEC (amended 92/31/EEC) and carries a CE mark
indicating conformity.
Applied Standards
Harmonised European Standard EN50081 part 1 and EN 50082 part1
for emission and immunity.
Radio products conform to ETSI EN300220 -1
…………………………………… .
L.G.H. Hatfield
Managing Director
Eltek Ltd.
1/7/2006
Date: …………………………
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