Have an rj3ib controller and when I power up the robot the i/o (for example Robot in auto bit to PLC) flashes on and off on PLC screen. This happens with all i/o on hot start.Is there a place in system variables or somewhere else that I can stop this? It seems to be a controller test on bootup.
The original problem is that I have 12 robots in one station welding a vehicle(spotwelding), If I have a problem I power down robots to repair. I power up the controllers and the robots crash (pounce to weld but do not run program they should be running). Program selection is through PLC( allen bradley I/O through data highway). PLC program is solid. I can't figure out the problem, i just noticed that the I/O flashes on and off on robot boot. This may be why program selection is wrong.

thnx

Hot start or cold start? I assume you meant cold start.

What signals are you waiting for to restart the robots? I was in the auto world for a long time and I am sure we can figure this issue out.

Send me the PLC program and let me take a look at it.

How are you doing program select? And what about a restart? It should be from some physical device. Palm button, PV reset button, operator button, etc.
Also, we usually wait until all robots in the interference zones are ready before we start and/or continue any.

What about interference zones? Are you using them?