The GE-Emerson IC697MEM731 Series 90-70 32-Bit CMOS Expansion Memory is installed as a daughter board and resides in the same slot as the module it serves. This board is required for the proper operation of these CPUs since the baseboard contains no RAM memory.
Memory is retained in the event of power loss by the battery on the baseboard housing. Flash memory is retained in the event of a power loss with or without the battery connected.
Logic program memory is continually error-checked by the PLC CPU as a background task. Memory parity errors are reported to the PLC CPU when they occur.
