Installation manual

Calibrating the Controller
900M050U00  Athena Controls, Inc. 18-5
18.4 Initiating the Calibration
To calibrate the controller after it has been prepared as described in 18.3
(including the fifteen minute warm-up period in standby mode):
1. For a 16C, 18C, or 25C controller, go to the CALCAL (calibration) menu and display CALoCALo
(calibration low). It will alternate with the process value for which you must apply a
simulated input (see 18.2).
2. To initiate low calibration in a 16C, 18C, or 25C controller, when CALoCALo is on display,
press the or key.
To initiate low calibration using a MODBUS write function, follow the instructions in
Using MODBUS Protocol with Athena Series C (1ZC, 16C, 18C, and 25C)
Controllers. (Special values must be written to the correct two MODBUS registers in
the same write operation.)
3. While the controller performs the calibration, the display on a 16C, 18C, or 25C will
freeze with CALoCALo on the lower line. When the low calibration has been completed,
the lower line will display donEdonE. (If the calibration is not successful, ErCLErCL (error
calibration) will be displayed. You probably did not supply the correct simulated
input. Fix the problem and try again.)
4. After successfully doing the low cal operation, you are ready to continue with the high
calibration procedure.
If you are using a “decade box” calibrator, thermocouple calibrator, or linear input
source, switch to the appropriate input for the calibrate high operation.
If you are using precision resistors for RTD calibration, remove power from the
controller, remove the low calibration resistor, and install the high calibration resistor
across the input terminals, then power up the controller. After powering up the
controller, wait fifteen minutes before proceeding to the next step. (This fifteen
minute wait for warm-up is required only if the controller has been powered down to
permit you to change a precision resistor at the input terminals.)
5. Display CAHiCAHi. (If CALoCALo is on display, press to display CAHiCAHi.) CAHiCAHi will
alternate with the PV for which you must apply a simulated input (see 18.2).
6. To initiate high calibration in a 16C, 18C, or 25C controller, when CAHiCAHi is on display,
press the or key.
To initiate high calibration using a MODBUS write function, follow the instructions in
Using MODBUS Protocol with Athena Series C (1ZC, 16C, 18C, and 25C)
Controllers. (Special values must be written to the correct two MODBUS registers in
the same write operation.)
7. While the controller performs the calibration, the display on a 16C, 18C, or 25C will
freeze with CAHiCAHi on the lower line. When the high calibration has been completed,
the lower line will display donEdonE. (If the calibration is not successful, ErCLErCL (error
calibration) will be displayed. You probably did not supply the correct simulated
input. Fix the problem and try again.)
If both the low calibration and the high calibration were successful, you are ready to
return the controller to service as described in 18.5.