Micrologix 1500 bit to say PLC is on?

Hello
I purchased a brand-new Micrologix 1500 controller for my project.
I have a line of code I want to execute anytime the PLC is active. Does the PLC have a "status" bit of some sort that I can use in my code to tell me "PLC = running"?

S:1/0 N.C. and S:1/1 N.O. in series and this caused the outputs to "chatter".

You appear to be talking about 'code' in the PLC. If it is being executed then the PLC is 'running'.

If the PLC stops 'running' then the outputs will be off.

If you put a line of code in file 2, it will be scanned anytime the PLC is "Running" (if that is what you mean by "active").

If the PLC isn't running, the code won't get scanned, but whatever bit you put on the output of the rung will remain in the state it was when the PLC was running.

However, if you can afford the luxury of using one of the outputs, your "line of code" could simply be "OTE O:0/0", which will energise the relay whenever the PLC is running, and if it stops running, or the power goes off, the output relay will "drop-out".

EDIT : I obviously type slower than Bernie

Where did you get those bits from? They are only two out of 5 for the mode status of the processor, and using them as you are isn't going to work.

Run Modes:


For all the codes and bit definitioons, see the table on page 392 of publication 1762-RM001G-EN-P.