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Storing a Program to the PLC:

the System is NOT Configured for Online Changes

If the GMR system is configured not to allow online changes, the PLC must be placed in

Stop mode to store a program or make a change to the GMR system.

Storing an Identical Program Following CPU Replacement

If a PLC is to be stored with an identical program, following replacement of a faulty CPU, then only the PLC to be stored to needs to be placed in Stop mode. The other PLCs in the system can remain online, providing output control.

When the new PLC is switched to Run/Enable mode, the GMR software compares its program checksum with that of the other online PLCs while it is initializing.

Storing a Revised Program

If a PLC is to be stored with a program that is not exactly the same as the program running in the other PLCs, then all PLCs must be stopped, and the same program must be stored into each.

The GMR software diskette includes a special utility that can be used to facilitate storing an updated application program in a system that includes SNP (serial network protocol) communications between PLCs. This utility is described on the following pages.

If the system does not include SNP communications, then the update must be done manually.

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GeniustModular Redundancy Flexible Triple Modular Redundant (TMR) System

GFK-0787B

 

User's Manual ± March 1995

 

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Image 177
GE GFK-0787B user manual Storing an Identical Program Following CPU Replacement, Storing a Revised Program