Ad590 Sensor Calibration - ILX Lightwave Temperature Controller LDT-5525 User Manual

3
C H A P T E R

AD590 Sensor Calibration

The following procedure is for calibrating the AD590 sensor measurement so that
the temperature measurement will be as accurate as possible. This procedure
calibrates the current measurement of the AD590. This procedure does not
calibrate C1 and C2. For information on calibrating the AD590 sensor, see
Appendix C.
Calibration may be aborted by pressing the OUTPUT switch.
22
LDT-5525
M A I N T E N A N C E A N D T R O U B L E S H O O T I N G
Calibration Adjustments
a Set the SENSOR SELECT switch (back panel) to the AD590 position. Set C1 to 0.00,
C2 to 1.00.
b Connect a precision 20 KΩ metal film resistor and a precision ammeter in series at
the sensor input of the LDT-5525 Temperature Controller.
c Enter the sensor calibration mode by pushing the MODE and SENSOR CAL
switches at the same time. After this, the TEC display will indicate sensor reference
current in µA. Wait for three seconds for the measurement to settle.
d Press and hold in the ENBL switch and turn the ADJUST knob until the display
indicates the same current as shown on the precision ammeter.
e Release the ENBL and wait for the VIEW SET indicator (LED) to be unlit. Replace
the 20 KΩ resistor with a 10 KΩ metal film resistor. Wait for three seconds, then
repeat Step d using the 10 KΩ resistor.
Ten seconds after the ENBL switch is released, the LDT-5525 Temperature
Controller will store the calibration data in non-volatile memory.
f Press the DISPLAY switch three times to rotate the display back to the SENSOR
mode. After calibration, I LIMIT will be automatically set to 4.00 Amps. Reset the I
LIMIT to the desired value.