Despatch LAD Series WITH PROTOCOL PLUS - Manual (Page 46)

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Sensor Calibration Page
The Sensor Calibration Page has parameters which can change the internal calibration
of the temperature sensor input signal. There is a low and high calibration point for both
the control sensor and the high limit sensor. To calibrate the instrument, allow the
control to warm up for at least 30 minutes.
To access the Sensor Calibration Page, enter the Setup Mode (see description earlier in
this manual). Press the Page key until Control Sensor is displayed. Press the Menu
key.
The control may have the optional process value retransmission output feature. The
output is a 1 to 5VDC signal. To calibrate the retransmit signal, the RetOutLo and
RetOutHi values from the Control Page must be known. You may bypass calibrating
the control and high limit sensor input to access only the retransmit calibration by
pressing the Menu key until RetCalLo is displayed (skip steps 4-17).
To re-calibrate the instrument:
1. Disconnect the control and high limit sensor thermocouples.
2. Connect a calibration instrument with a type J thermocouple output to the
control sensor input. Allow the control to warm up at least 30 minutes.
3. Access Setup Mode.
4. Press Page key until -100F is displayed.
5. Press Menu key until Ctrl Sens -100F is displayed.
6. With Ctrl Sens -100F displayed, adjust the calibration instrument to Type J
thermocouple, -100 degrees Fahrenheit output.
7. Wait 30 seconds. Press the key.
8. With Ctrl Sens 1400F displayed, adjust the calibration instrument to 1400
degrees Fahrenheit output (Type J thermocouple).
9. Wait 30 seconds. Press the key.
10. When the control displays Ctrl Sens Done, disconnect the calibration
instrument from the control sensor input and connect it to the high limit sensor
input. Reconnect the control sensor thermocouple.
11. Press the Menu key until HL Sens -100F is displayed.
12. With the control displaying HL Sens -100F, adjust the calibration instrument
to -100 degrees Fahrenheit output (Type J thermocouple).
13. Wait 30 seconds. Press the key.
14. With the control displaying HL Sens 1400F, adjust the calibration instrument
to 1400 degrees Fahrenheit output (Type J thermocouple).
15. Wait 30 seconds. Press the key.
16. When the control displays HL Sens Done, disconnect the calibration
instrument from the high limit sensor input. Re-connect the high limit sensor
thermocouple.
17. To skip calibration of the retransmit signal, press the Page key twice to exit the
Sensor Calibration Page.
18. To calibrate the retransmit signal, press the Menu key until RetCalLo is
displayed.