Parameter Setup; Sensor Cal - ILX Lightwave LDT-5525 User Manual

The temperature is limited (via the sensor feedback) to the T LIMIT value. If the sensor reads a temperature which is
greater than T LIMIT, the I TE output will be shut off.
The GAIN value is used to control the sensor feedback gain, and thus the temperature settling time and overshoot. If
the GAIN is set too low (1 is the lowest setting) the TE cooler will take longer to reach the temperature set point. If
the GAIN is set too high (300 is the highest setting) the actual temperature may oscillate around the set temperature.
The optimum GAIN setting depends on the type of TE cooler and temperature that you are setting . Set the GAIN to
its lowest value and then try increasing it until the temperature oscillates around the set temperature. Then, reduce
the GAIN one step.

2.4.4 Parameter Setup

The PARAMETER switch is used to view and edit the parameters. Repeatedly pressing the PARAMETER switch will
cycle through the parameters.
When a parameter is selected for viewing, its value will remain on the display for three seconds. If an adjustment is
made to the parameter (by turning the adjust knob) the three second timer will be restarted. Three seconds after the
parameter adjustment is done, the display will revert to the last measurement mode.

2.4.5 SENSOR CAL

These are the constants of the Steinhart-Hart equation that the user enters to calibrate the TEC for different
thermistors' temperature conversions. The Steinhart-Hart equation is used to derive temperature from the non-linear
resistance of an NTC (Negative Temperature Coefficient) thermistor. For information on setting C1 and C2 for
thermistors, see Appendix A. For information on thermistor selection and sensor current selection, see Appendix B.
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