Installation manual

Calibrating the Controller
900M050U00  Athena Controls, Inc. 18-3
18.2.3 Simulating Thermocouple Input for Calibration
When calibrating the controller for use with a thermocouple input, you will remove the
output wiring. You will remove the input wiring and substitute a simultated input provided
by a thermocouple simulator.
Before calibrating the controller, you must determine the correct temperature input values
to simulate during calibration. Two values are used, one for low calibration and one for
high calibration. The temperatures to be simulated depend on the specific type of input.
The values can be read from the CALoCALo (cal low) and CAHiCAHi (cal high) parameters in the
CALCAL (calibration) menu as described in Section 13.
For example, if the InPInP (input) menu tYPEtYPE (type) parameter is set to J thermocouple and
the UnitUnit (unit of measure) parameter in the dSPLdSPL menu is set to FF (Fahrenheit), then the
calibration low value displayed will be 32 and the calibration high value displayed will be
1258.
Set the thermocouple simulator accordingly when performing the calibration procedure
described in this section.
18.2.4 Simulating Linear Input for Calibration
When calibrating the controller for use with a linear input, you will remove the output
wiring. You will remove the input wiring and substitute a simulated input provided by a
milliamp input device, millivolt input device, or voltage input device, depending on the
type of input you plan to use for control.
During calibration, you will simulate two process values: one for low calibration and one
for high calibration. In the case of linear inputs, these are usually the process values that
are configured for the SCL.LSCL.L (linear input scaling low limit) and SCL.HSCL.H (linear input scaling
high limit) parameters in the InPInP (input) menu. These scaling values are the values
displayed for the CALoCALo (cal low) and CAHiCAHi (cal high) parameters in the CALCAL (calibration)
menu as described in Section 13.
Configure the input scaling parameters SCL.LSCL.L and SCL.HSCL.H before calibrating the controller.
During calibration, use the lowest input value for the calibration low value and the highest
input value for the calibration high value. For example, if you plan to use a 0 to 20 mA
input for control, then apply 0 (zero) mA to the input terminals during low calibration and
20 mA to the input terminals during high calibration.