TE Technology TC-24-12 - Manual (Page 8)

8
Setup
11.0 Controller Set-Up
Setup Note: See “Component Identification, Controller Wiring Diagram, and Mechanical
Drawing Package” for additional reference.
11.1 Attach the thermistor to the control location. Generally, this is the cold side of the cooler
rather than the part itself that is to be cooled/heated. This provides better control stability
although there may be a temperature difference between the cooler and the part. Attach
the thermistor wire leads to JP3-9 and JP3-10 (polarity is not important).
NOTES:
As much wire length of the thermistor should be thermally connected to the cold side as
possible. This will help eliminate errors resulting from heat conducting along the wire
leads and affecting the sensor reading. If this is not done, the thermistor wires will be at a
different temperature than the cold side and they will add or remove heat in the region of
the thermistor, making the temperature reading less accurate. By “pre-cooling” the
thermistor’s wire leads, the thermistor’s temperature will be allowed to assume the
temperature of the cold side as closely as possible. “Pre-cooling” can be accomplished by
placing aluminum tape over the wire leads and adhering it to the cold side of the cooler.
Different thermistor heads are available. See “Thermistor Styles for TC-24-12” for
information on standard ones available. One MP-2379 thermistor is normally supplied
with the TC-24-12.
For over-temperature protection, additional thermistors or thermostats can be wired up to
JP3-5/JP3-6 and JP3-6/JP3-7.
11.2 Connect the appropriate DC power supply [(10.8 to 26.4) volts] to the controller by
connecting the positive lead (+) to JP3-1 and the negative lead (-) to JP3-2. Turn the
power supply on. DO NOT CONNECT THE CONTROLLER TO THE TE MODULE AT
THIS TIME.
11.3 Adjust the Set Temperature using potentiometer R13. The voltage across TP3 and TP2
(common) can be used to interpret the Set Temperature. The potentiometer range
corresponds to -20 °C at full counter-clockwise (0 Volts at TP3) to +100 °C at full
clockwise (5 V at TP3). This is a 25-turn potentiometer, so each full turn corresponds to a
4.8 °C change in the Set Temperature. The “Temperature vs. Sensor/Potentiometer
Voltage” graphs and tables show the relationship between voltage and Set Temperature.
This step allows the user to set the Set Temperature at a desired level before applying
power to the thermoelectric module(s).
11.4 Turn the power supply off. Then connect the thermoelectric module positive lead (+) to
JP3-3 and the negative lead (-) to JP3-4. Turn the power supply back on to begin
controlling the temperature.