Not Listening To Advice

We recently hired several overseas representatives to maintain our customers machines internationally. However it seems when
they ask for help they do not follow our advice initially
and the machine is down several days because of this. Then
they go back to what we told them to look for in the beginning. Is this the "norm" in this new world economy? Just wondering?

Its been the norm since we came down out of the trees and picked up a rock for a tool.

We had a commisioned well running machine down for two weeks because the technical people onsite kept insisting the PLC program was at fault. In my first e-mail to them I told them to check the associated external hardware and wiring first but according to them this was not not the problem it was the pLC program. In the end it was a bad relay......

"Program" issues are my biggest source of income. After I drain the water from the air system so the valves will again work I have the urge to smack someone alongside the head with a 2 x 4. Instead I just smile and send them a large bill.

If its not on fire it must be the logic; darn plc guys anyway.

jstolaruk said:

If its not on fire it must be the logic; darn plc guys anyway.

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I'm stealing that quote!

People have a tendency to blame any problems they can't readily explain on that part of the system they understand the least. In many cases, that's the PLC (the program). Too lazy to track down a photocell that's bent out of alignment? Blame it on "the program". Going get dirty if you have to climb on the machine to see if the driveshaft spins freely? Must be something wrong with the PLC.

One of the most difficult concepts to get through some peoples' heads is that PLC programs don't wear out. In over a quarter century of dealing with PLCs, I have seen plenty of cases where a PLC's memory got corrupted without any human intervention. But I have never encountered a case where a PLC's memory spontaneously changed in such a manner that the PLC was able to continue running.

To jvjr:

It looks like your company needs to reevaluate the service firm you hired and/or the amount of training you provided their technicians on the details of your machines.

Steve Bailey said:

One of the most difficult concepts to get through some peoples' heads is that PLC programs don't wear out.

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I had been putting the same idea as follows: a calculator cannot give you a wrong answer: it is either working or dead.

Steve Bailey said:

People have a tendency to blame any problems they can't readily explain on that part of the system they understand the least. In many cases, that's the PLC (the program). Too lazy to track down a photocell that's bent out of alignment? Blame it on "the program". Going get dirty if you have to climb on the machine to see if the driveshaft spins freely? Must be something wrong with the PLC.

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The one we get hit with most frequently is "this motor overload keeps tripping, can you check the program and see what's going on?"

Steve Bailey said:

One of the most difficult concepts to get through some peoples' heads is that PLC programs don't wear out. In over a quarter century of dealing with PLCs, I have seen plenty of cases where a PLC's memory got corrupted without any human intervention. But I have never encountered a case where a PLC's memory spontaneously changed in such a manner that the PLC was able to continue running.

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Had one once that was close. PLC-2/30s using UPDOC to monitor/program. Only on one processor (of 17) and only when looking at a particular part of the program. It took months to figure out because it happened so infrequently and was so obscure. It's been awhile but it seems it was something like a timer preset getting changed to some nonsense value like "BA2". The repeatability of it was really strange. Caused a bit of finger pointing amongst the electronic guys. It was finally decided that UPDOC was the cause - so, technically the PLC program didn't spontaneously change. Bizarre nonetheless.

Doug-P said:

The one we get hit with most frequently is "this motor overload keeps tripping, can you check the program and see what's going on?"

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lol, had that one yesterday.

jstolaruk said:

lol, had that one yesterday.

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This is a common one.Same happended to me 3 weeks ago.

I am in the middle of swapping over an old PLC to Contrologix. After switching the plant to contrologix next day an operator complained to me that a particular motor had tripped and he had reset the overload 3 times and 'my program' was still tripping the motor. They found a metal bolt wedged somehow into the equipment. I guess a loose nut behind the keyboard caused that issue.

Training On The Job

Hi JVJR,

Training on the job for these new representatives could be a part of your solution. It seems that they don't know your machines. And they have a hard time understanding you.

You could give these guys a training in person. This has several advantages. It's more easy for you to explain things, they are able to pose questions more quickly, and most of all you get to know each other personally, which creates a bond. This is important when future problems arrise.

We get the same over here.

Production had a problem once and I was told to sort it,(I knew there was nothing wrong with the machine).I plugged in to the PLC connected to the wireless and surfed the net for 30min. I then shut down the PC and told them the problem was fixed. They were delighted and told me how well the machine was operating. Easy-money.

On a serious note maybe you should get some remote software so you can log into the machine and prove it isn't the PLC(which you knew anyway)and you could tell them where you suspect the problem is and get them of there backsides and maybe they will start to poke in the correct location while you sit back and drink coffee while getting payed. zzzzzzzzz. He He.

"When all you have is a hammer.........every problem becomes a nail"

just my $.02

I guess that would be difficult if you were at the mercy of your techs onsite. It is so common to be called on site for a "program" problem that I just consider it normal (yeah the system has been working unchnanged for 10 year but it must be in the program). Usually it just shows that their external troubleshooting capabilities are just as poor as their understanding of the program. Hey sometimes being able to go into the program and track down the issue from that side does make it quicker to solve the problem. Just part of the territory. What gets me is going to a meeting a plant and being called a little later because they are having problems. Like me just being there in the same facility could somehow affect the system. I am still trying to figure out whether that means they think I am that good or I am that bad... Well they keep coming back so I guess that means I am doing something right!