Override Key on AB PLC's

I feel davidhinch's pain...

I once worked on a large brewery project where I got short straw and had night-shift commissioning/trials to do. I needed to make some changes on a remote PLC, but someone had put it into RUN position.

I had to walk the 2 miles there, turn the key, then 2 miles back, to do the changes.

Needless to say most of those 4 miles were outdoors...

It was 3:30 a.m., about -8 deg.C, windchill probably made it feel more like -15, and it had been snowing.

I eventually discovered who had put it into RUN, and I told him next time he did it I'd make him take a walk.....

I thought we had it bad with maintenance who would randomly adjust timers (physical ones) or sensors on our machines for almost no reason.

2 miles! May as well have just drove there your employers should've had an onsite golf cart lol.
 
... 2 miles! May as well have just drove there your employers should've had an onsite golf cart lol.

There was no need to go there... Or, there wouldn't have been if the guy working in that area earlier that day hadn't left it in RUN...

Perhaps I exaggerated the 2 miles bit, let's say 1.5, still a fair trek in the dark, freezing cold wind, on untreated footpaths...

(Someone stop me, before I milk it some more..🤾
 
So no one here has never had to cycle the key switch and not had a key? The AB key is a joke and anything from a small screwdriver to a paper clip can work if needed, so if they really want to turn it hiding/locking up the key will do nothing.
 
Its a long story, however there is an electrician that keeps turning it to run and throwing away the key.

I would love to hear that story! From the "Bubba" side of things my guess is he is tired of changes mysteriously appearing in the program. Usually, coffee, a box of doughnuts, and an honest conversation will resolve issues like this.


Bubba.
 
We have the very same problem here, however most are not throwing away the key but they are always putting the processors into program mode, and have no idea then how to go back to run mode. The worst thing is, they are switching the key as a desperate attempt to restart the machine when troubleshooting the original cause doesn't turn up an issue that was likely related to a misaligned photo eye or a blown fuse. Sometimes I know they have been at it cause I will try to work on a system remotely only to discover that somebody has switched us to RUN instead of REM RUN.
However, when I ask who and why, it is oddly strange that nobody did it.


:oops:

why dont you put an annoying blinking message somewhere in the screen, so that they put the switch back to REM RUN voluntarily?
 
why dont you put an annoying blinking message somewhere in the screen, so that they put the switch back to REM RUN voluntarily?

I shouldn't have to , these are "trained", "skilled" people, so they say.
My theory is, if you don't know what it does than leave it the **** alone!!
No matter if were talking about a key switch on a processor or a machine setting.
 
I'm not subscribing to the physical violence solutions... that may be because I'm not a military person, never have been, and at my age unlikely to be conscripted.....

Anyway, back to the original problem, someone is turning a key to RUN when it should, allegedly, be in REM.

We need to be clear whether this is company policy, or simply a "polite request" from the programmers.

If "Company Policy", then it's an open and shut case for the management to deal with as they see fit.

If the latter, then it's an open and shut case for the management to deal with as they see fit.

Of course, we may well find that "company policy" demands that all keyswitches should be in "RUN", which puts a whole different slant on the discussion. Or we may well find that there is no "company policy" on this at all, in which case it is time to sit round a table and discuss it.....

..end of..
 
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It sounds dangerous editing a plc program while someone is working at the same machine, is it a standard procedure?
 

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