Compactlogix L32 Major Fault Recording

Hi Guyss:

I was given a PLC program to take to the site and start up a system. there is one Rung in this progam that tries to use GSV to record controller Powerup and I/O fault. It uses a DINT and monitors the second (PLC ALARM.1) and fourth (PLC ALARM.3) bits of it using XIO type of contacts.

it doesn't seem to be working, probably due to the wrong type of contact, as when I checked the DINT it was all zero.

The GSV parameters are as follows:

Class Name: Fault Log
Attribute Name: Major Faults bit
Dest: PLC_ALARM

Any Idea if this is is how we can get those faults?

Regards

Is this code inside a Fault Routine, inside a Powerup Routine, or inside a normal Routine that's part of a normal Task ?

That timer .DN bit that conditions the GSV won't turn on in a Fault or Powerup routine; those routines are executed only once.

it's insided a normal routin. Ican take the timer out. would this make it work?

Logic like this is placed in the Fault Routine or in the Powerup Routine because those are executed in times that the controller can be in a fault mode.

Since the controller does not run any of its normal program when it is in Fault mode, this logic will never capture a fault code.

I don't use Fault Routines often, but it is my impression that the Major Fault Bits tag only contains the current fault, not the previous one that's recently been cleared.

I'd recommend placing this code into a Fault Routine.