whumphrey
Lifetime Supporting Member
I am having a strange intermittent problem with a ControlLogix system appearing to drop discrete inputs momentarily when we first go online with the processor. This has happened at least twice that we know of but is not consistent.
System is redundant ControlLogix L62 (1756-RM redundancy modules), firmware version 19.53, with Ethernet I/O via 1756-EN2TR modules operating in a ring.
Here is what we observe....
Several motor run command outputs are held up by a sealed in logic rung. The entier rung is conditioned by an "in remote" digital input that is always on. Below is a simplified schematic.
remote startpulse stop pulse run cmd
----||----------||------------|/|------------()--------
| |
| |
| run cmd |
|---||------|
Twice now, when we go on line, the motor run commands which were on are now off. There is no evidence of a rudundancy switchover. Equipment in Auto mode will go off momentarily then on again.
We have programmed several traps to try and catch the root of the problem and are waiting for it to occur again. I'm just wondering if anyone has experienced anything similar.
System is redundant ControlLogix L62 (1756-RM redundancy modules), firmware version 19.53, with Ethernet I/O via 1756-EN2TR modules operating in a ring.
Here is what we observe....
Several motor run command outputs are held up by a sealed in logic rung. The entier rung is conditioned by an "in remote" digital input that is always on. Below is a simplified schematic.
remote startpulse stop pulse run cmd
----||----------||------------|/|------------()--------
| |
| |
| run cmd |
|---||------|
Twice now, when we go on line, the motor run commands which were on are now off. There is no evidence of a rudundancy switchover. Equipment in Auto mode will go off momentarily then on again.
We have programmed several traps to try and catch the root of the problem and are waiting for it to occur again. I'm just wondering if anyone has experienced anything similar.