Parameter Generation and Control 9354-4250, Installation And Operation Manual

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PGC, Inc. Appendix B; SmartPad version 0.503 Steady State & Programmable
November 2005 B-17
Aux RTD Calibration Screen (Steady State and Prog Modes )
A second RTD can be accessed for calibration from the SmartPad. This is an optional sensor
that may not be present on every system. (Note that when the controller is configured for
reactivation control in dry mode, this RTD will be the reactivation temperature sensor). The
controller converts the auxiliary RTD resistance to a digital temperature measurement using a
16-bit A/D converter. The offset (zero) and scaling (span) of this A/D converter input can be
adjusted from the SmartPad keypad. Refer to the system user manual for step by step procedures
to make this adjustment.
REF. VALUE Enter the temperature that should be displayed by the water temperature
measurement circuit.
Aux RTD ZERO Calibration Screen (Steady State and Prog Modes)
The first step in calibrating the auxiliary RTD is to set the zero or offset value. This value
should be as close as practical to the minimum operating temperature.
ACTUAL VALUE: will indicate the current auxiliary temperature, as it is measured by the input
circuit. This value will change to indicate the calibration offset, after the CAL key is pressed.
REF. VALUE will indicate the reference value entered in the water RTD calibration screen
Aux RTD SPAN Calibration Screen (Steady State and Prog Modes)
AUX RTD ZERO CALIB
ACTUAL VALUE 03.9
°
C
EF. ACTUAL 04.0
°
C
CAL DONE
Key for function keys action
F1 = CAL: instructs the A/D converter to
accept the new zero offset value.
F2 = no function
F3 = no function
F4 = DONE: allows the user to exit the
screen after the offset value has been
accepted. Returns to the auxillary
RTD calibration screen
AUX RTD CALIBRATION
REF. VALUE 03.9
°
C
ZERO SPAN NEXT ESC
Key for function keys action
F1 = ZERO: access the zero adjust screen
F2 = SPAN: access the span adjust screen
F3 = NEXT: access other RTD calibrations
F4 = ESC: return to process variable
screen