PicoLog Self-Help Guide
AR346-1
© Copyright 2014 Pico Technology Ltd.
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Using the DD100 thermistor from the DrDAQ on the PicoLog 1216
To use the DD100 thermistor from the DrDAQ with the 1216, you will need to cut off the
4-pin connector and just use the two outside wires to connect to the 1216 terminal
board. (The two inside wires just connect to a fixed resistor which is only used with the
DrDAQ.)
Connect one of the outside wires (does not matter which) to one of the Gnd terminals of
the 1216 terminal board. Connect the other outside wire to the C1 (Channel 1) input
terminal of the 1216 terminal board. You will now require a 39 kΩ resistor to connect
between the channel 1 input and the +2.5 terminal of the 1216 terminal board. If this
resistor has leads, you can easily connect it by clamping it in position using the terminal
screws C1 and 2.5. If you can only get a surface-mount 39 kΩ resistor, you can mount it
in the R33 position on the terminal board as shown in page 4 of the PicoLog 1000 Small
Terminal Board User’s Guide (see Related Documents).
Assuming you have connected up the sensor, resistor and supply as described above,
you just need to set the scaling for the channels in question. Below is an illustration of
how to set-up channel 1 for temperature measurement from –10°C to +100°C using a
DD100 sensor.
1.
Start PicoLog and set-up your sample rates as required.
2.
When you get to setting up Channel 1 (PicoLog 1000 Channels), highlight
Channel 1 and click Edit.
3.
Type Temperature as the Name.
4.
Now click Options. (You might be asked to save the present setup. If so, click
OK).
5.
In the Parameter Options dialog box tick Use parameter Formatting, put °C in the
Units box. Field Width = 5, Decimal places = 2, Minimum value = -10, Maximum
value = 100. Now click Scaling to go to the next dialog.
6.
In the Parameter scaling dialog box, select Table Lookup as the Scaling method
and in the text box, copy and paste the table below exactly:-
2.247 -10
2.152 0
2.020 10
1.848 20
1.643 30
1.417 40
1.187 50
0.970 60
0.777 70
0.614 80
0.481 90
0.375 100
(Please note there is a single space between the pairs of numbers.)
This tells the program to equate 2.247 V to –10 °C on the graph and 0.375 V to
100 °C on the graph (plus intermediate values).
7.
Go OK to go back through the open boxes and channel 1 should now be scaled
from –10°C to +100°C.
Look through the PicoLog manual for information on using PicoLog or click on the Help
button at any stage in PicoLog.
