I'm hoping for a little insight into the following issue I have with the following PLC configuration: CPM2C-20CDR-D (1) CPM2C-16ETC 16pt expansion module connected to a G7TC-OC16-DC24 relay block (4) CPM2C-TS101 2ch RTD modules It has been in operation for about 11 years or so and within the last year or so, the PLC would occasionally error out. The customer would cycle power, the error would reset and continue operation. In the last couple months, the error was occurring more frequently to the point of at least a couple times a day. I contacted Omron and they thought the problem may lie in the power supply circuitry of the CPU. The CPU was replaced and am being told that in the last couple weeks, it has errored out twice since. So, now I am beginning to suspect field wiring as a possible cause? My question ... if there is some noise induced into the RTD lines, could that be a cause for the PLC to generate an I/O bus error and making the PLC fault? Thanks.
