Code Assistance PLS

Greetings,
I have a press that must come all the way down to complete a full cycle, obviously every time. However, sometimes it fails due to some type of mechanical condition, i.e. something is jammed, mechanical stops get out of adjustment, etc. I dont want the answer to my code woes, but I really would appreciate an assist. I have spent some time doing this to no avail. I was trying to use OSR, WORD COMPARES, but sigh I am doing something wrong. I am using a ML 1000. I need the auto cycle to stop if the FULL DOWN LIMIT SWITCH is not made every time. This will need to be reset using a PB, which I can do that part, hmmmmm. Thanks in advance.

Ed

Never used an ML1000, so I don't even know what commands it has, but if I was doing it with an AB PLC, I'd use a timer which I would reset if the prox was made or the PB was hit. Make the timer start when the cycle starts and set it for slightly longer than the length of time a "good" cycle takes.

A ml1000 is an micrologix 1000 an ab plc. I agree i would do the same as tcig just start the timer from the down signal and reset it it from the down sensor if it doesnt make before the timer is done halt the operation.

Not too long ago I built an automated stamping press that uses a ML1000. I did just as the others stated and set a timer that runs at the start of each cycle and is reset by the down prox. There is also a timer that checks to see if the punches have returned to the up position. If either of the timers times out or if the down prox and the up prox are both on at the same time a fault bit is set and auto mode is dropped out. (unlatched, cleared, ect)

What happens if one of the prox. signals stays on all the time?

Do you need a manual and auto control?

It seems to me with a press I would want to know the position of the platen/press at all times. It would help you sleep better.

Some presses are using rotary encoders or PLS (Programmable limit switches) connected to the crankshaft or clutch to determine position.
Maybe you could use something like this to sense position, then program it into the ML1000.

Looks like I HAVE used an ML1000 after all!