ILX Lightwave LDT-5525 User Manual page 44

V. AD590 Sensor Calibration
1______ Set C1 to 0.00, C2 to 1.00.
2_______ Set the sensor select switch to "AD590" (-04-).
3_______ Connect the 5525 Sensor Test Fixture to the output connector of the 5525. Set the 5525 Sensor Test
Fixture to SENSOR 4, Load 1. Connect a micro-ammeter to the white and black banana pins on the
5525 Sensor Test Fixture. There should be about 266.5 µA through the sensor resistor.
4_______ Hold down both the "MODE" and "SENSOR CAL" buttons. This will put the 5525 into "Sensor Cal"
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mode.
5_______ Allow the sensor measurement circuit to settle, usually about 3 seconds.
6_______ Hold down the "ENBL" button and turn the knob until the display reads the number of microamps
through the resistor.
7_______ Release "ENBL", wait for "VIEW SET" light to go out.
8_______ Set the 5525 Sensor Test Fixture "Load" switch to position 2.
The current on the micro-ammeter should be about 398.5 µA .
9_______
10______ Hold down the "ENBL" button and turn the knob until the display reads the number of microamps
measured..
11______ Release the "ENBL" button.
12______ Wait for the automatic set point cal procedure to complete - about 10 seconds.
Check the sensor cal: Press display button several times to rotate the display around to "Sensor °C".
13______
Display should read about 87.4°C. Set the 5525 Sensor Test Fixture to the "Chk" position. Measure
the current (in µA) Isense through the sense resistor. Check that the display reads Isense - 273.2,
within ±0.1 °C.
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Calibration can be terminated at any time by pressing the "OUTPUT" button. This will stop cal; no constants will
be saved to EEPROM.
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It doesn't matter which value resistor is used first.
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