Maintenance
Replacement Procedures
CAUTION
TO PRESERVE THE CONTROLLER CONFIGURATION PRIOR TO PERFORMING ANY REPLACEMENT PROCEDURES OR REMOVING POWER TO THE CONTROLLER:
•Be certain that the LoBatt LED is OFF. (MEMORY – LOW BATTERY diagnostic is not active.)
•Force a cold start of the controller by setting the manual mode switch on the controller to PROGRAM and then to RUN and allow the controller to complete its start up sequence. Controller configuration files will be backed up to the flash PROM on the CPU.
•When powering up the controller, the controller performs a warm start provided that the battery power to the RAM has not been interrupted. If battery power to the RAM has been interrupted, the controller performs a cold start at power up and,
−The controller real time clock setting is lost and must be reset.
−Any field calibration values to the AI modules and CJ references are lost. If AI modules or CJ references were required to be field calibrated to achieve greater than 0.1 % accuracy, you must recalibrate those modules.
•If the CPU module is replaced, a valid configuration file must be downloaded to the controller. Also field calibration of the AI module and the CJ reference are lost. If greater than 0.1 % accuracy is required for the AI module or CJ reference, you must field calibrate the module.
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