GE fanuc plc trip

hi
I have system control with ge fanuc plc, the cpu is CGR772 and cpu connect to i/o with GBC and NIU.
GBC: BEM713
NIU: IC200GBI001
I/O CARD: IC200ALG240 (Analog input cart)
Power I/O cards: ic200pwr002
my system control is working, but in some days PLC read zero from some channels analoge input card and then PLC Triped and all system control Droped doewned. when i reset power of I/O cards the system again workinig.


analog input card config: span low=4000,span high=20000, default=0


why PLC read zero from analog input card?


thanks for your help.

The default = 0 option means that when the CPU loses communication with the I/O modules on the drop, the analog signal is driven to zero. The alternative is to hold the last value before the communications loss.
What kind of entries are you seeing in the I/O fault tables?

Steve Bailey said:

The default = 0 option means that when the CPU loses communication with the I/O modules on the drop, the analog signal is driven to zero. The alternative is to hold the last value before the communications loss.
What kind of entries are you seeing in the I/O fault tables?

Click to expand...

Hi
I received "Low Alarm", "Low input", in I/O fault table.


may be this problem cause of card hang up? or just default=0 in I/O config is cause of this problem?


my default in I/O config: "default=0"

And

"%AI default/Hold last state"= default


can you help me how can i solve this problem and what changes need to do?


thanks.