Lost Data Memory and SCU Settings

[richard 0]

Hello All,

I have a problem within 2 PLC's here in my plant. Both are CJ2H-CPU64-EIP. They are running almost identical programs just different lines.

When the problem occurs the PLC drops out. I get no alarm on the PLC. But when I start to recover from the drop it has caused all D Memory to be 0 and I lose protocol macro settings within the SCU Card attach to the PLC. Has anyone ever had a similar issue. If so is there an easy fix?

 

Thanks for you support

 

[BobB 58]

No - the data memory is backed up by a battery.

[lostcontrol 23]

I’ve seen something similar once before.

cant recall the CPU version, but all the module config settings had been cleared out.

this rack had a SCU as well from memory

[innoaloe 59]

The only fix you can do to ensure operation even without battery, is to set the D Memory area which is used for SCU settings on the programs First_Cycle (using P_FirstCycle at the topmost ladder).

That said, you need to insert all settings properly.

[richard 0]

To further this issue....

I get an I/O bus error when it happens. The manuals are very unclear for these issues.

Code 80CF/0F0F   IO Bus error F

 

Edited 27 Jul 2018 by richard

[BobB 58]

Is it possible the machine is shaking the PLC causing the bus connectors to disengage? Have you taken the PLC apart and reconnected the bus? Is it possible that the connector slides are not made properly? I/O Bus Error is often a mechanical issue like this.