Parameter Generation and Control 9354-4250 - Page 39

PGC, Inc 500-1000 CFM Air Handler May 2006
Appendix A A-23
Water RTD Calibration Procedure with Precision Resistors:
1.) Zero Offset, or Single Point Offset.
a. Place the low temperature precision resistor in the RTD circuit.
b. Access the RTD calibration screens in the SmartPad™:
• On the Process Variables screen, press MORE (F4), then PREF (F2), and
enter the access code(factory setting: 0000) to access the Area modification
screen.
• Press CAL (F3) to access the Water Calibration screen.
b. Enter the temperature measured by the reference standard and press ZERO (F1).
c. Press “CAL” (F1); after a few seconds, observe the Actual Value matches the
Reference Value.
c. Press “DONE”.
2.) Span (Gain) Adjustment:
a. Place the high temperature precision resistor in the RTD circuit.
b. Access the RTD calibration screens in the SmartPad™:
• On the Process Variables screen, press MORE (F4), then PREF (F2), and
enter the access code(factory setting: 0000) to access the Area modification
screen.
• Press CAL (F3) to access the Water Calibration screen.
c. Enter the temperature represented by the precision resistor and press SPAN (F2)
d. Press “CAL” (F1); after a few seconds, observe the Actual Value matches the
Reference Value.
e. Press “DONE”.