Dangerous novices programming plc's

Killercal said:

Maybe I’m wrong, but isn’t this supposed to be a “Help” website? Rookie programmers are going to be the ones with the most “Basic” questions because they are green. One thing that bugs me the most are “senior” programmers who think that everyone should know what they all know when in reality, they learned everything from experience or asking questions when they were rookies. Lets not bash new/green programmers or even experienced programmers who are now learning some new technology. I’ve experienced learning new technologies through manuals, test benches and asking experienced programmers, and I find that asking people who have experience to be the most helpful! Some manuals leave out some very important things that aren’t intuitive. If you only take one thing out of my rant here, please take this! Any programmer, new or old (experienced), that come across a program that you see will case issues, let the person who programmed it know. The person that programmed it either overlooked it, doesn’t know he programmed it wrong or had “fat finger syndrome” and needs this to be pointed out. This is how we all learn! That said, I know to check, re-check and check again all my programming before I deploy it and I’m just here to help out others and get help from others.

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The problem isn't with the "green" programmers who are asking questions with the honest intent of truly learning and improving. The problem is with those who are looking for the shortcut or someone to do their work for them. The problem is with those who aren't willing to do their own research first, who won't do their own homework, who won't put in the effort. The problem is with those who think they know it all right out of the box because they have a piece of paper or because they can beat all their buddies on XBox. The problem is with those who don't really want to learn, or don't care about safety, or don't care about proper practice.

And TACM is right -- safety is EVERYONE'S RESPONSIBILITY. There are many of the pro's here for whom I have the greatest of respect, even though we've never personally met. But if we were working together, I would NOT trust their LOTO -- I'm going to put mine on anyway, and then I'm going to test it to make sure it's safe. I'm not going to trust them with my life.

OZEE said:

The problem isn't with the "green" programmers who are asking questions with the honest intent of truly learning and improving. The problem is with those who are looking for the shortcut or someone to do their work for them. The problem is with those who aren't willing to do their own research first, who won't do their own homework, who won't put in the effort. The problem is with those who think they know it all right out of the box because they have a piece of paper or because they can beat all their buddies on XBox. The problem is with those who don't really want to learn, or don't care about safety, or don't care about proper practice.

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I agree with your statmet!

I don't have the time to read everything here so this may have been covered already. I think the problem is not with green programmers, because everyone is a green programmer at some point. The problem is with supervisors throwing green programmers into the fire with little supervision. I got my start in this field at a place like that, actually had the owner tell me once it was cheaper for to park at a job site for month to figure it out myself than for him to come down and help.

Even the "master control relay" bit worries me if you think a MCR in software is a safety device think again.
Switching off the outputs by removing the supply to them with a safety relay is the real answer
anyway I also get worried about untrained engineers messing with plc programs but not novices (these are just as we were many years ago) it's the ones that think they can program & decide to "do a quick Mod" that worry me more.
A novice is usually someone who hopefully is under some experts wing or at least only writing programs in the classroom & not on a live system.
I had a simular experience with an Engineering manager that reckoned he could load HMi's & do small mods.
One day while on holiday I got a call from him asking me for the logon to the "programming laptop" as he had a problem he needed to go on-line to find a problem.
After reluctantly giving him the password I continued on my well earnt rest with the phone switched off.
Next day when I arrived at work I was presented with my laptop & a mesage to the effect could I put the software right on the machine after the engineers have straitened out everything on it?.

I think the problem is that years ago before plc control it took a qualified Electrician to build control systems with good old relays, timers and contactors. Unless you had good knowlege of the relevant regulations how to wire safety systems this is a task that would be seldom attempted by a novice. Most Electricians moved on to PLC control with ease because they had a good background already.

andysherris said:

I think the problem is that years ago before plc control it took a qualified Electrician to build control systems with good old relays, timers and contactors. Unless you had good knowlege of the relevant regulations how to wire safety systems this is a task that would be seldom attempted by a novice. Most Electricians moved on to PLC control with ease because they had a good background already.

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A lot of good points being made in this thread, especially the onces about how everyone was a beginner at some point. My 2 cents is that just because someone is a programmer, that does not make them an engineer, electrical-mechanical repairman, or electrical designer. It also doesn't mean they can't learn to be one of the above. It takes time.

One of the beautiful things about skilled trades is the apprenticeship program and how they should be learning their trade while working with a pro...and part of the journeyman's job was to teach the apprentice. I know it didn't always work that way but when it did it was a beautiful thing.

Parky I liked your tale about the laptop.

I had a similar experience with a robot. I am definately not an expert but have just lived with it for 3 years.(Background: I was not getting on very well with my boss as he wanted me to work shifts!!!) I was on holiday and found this out after I came back: It stopped and would not go. A number of my colleagues fiddled and it STILL would not go. My boss paid for an Engineer to fly down from Scotland to fix it. He cancelled the program, reloaded it and flew home.

"Why didn't you call me said I.....?"

Seasoned programmers never make dumb mistakes?

Derek said:

Seasoned programmers never make dumb mistakes?

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Ha! I laugh at that comment!

andysherris said:

I think the problem is that years ago before plc control it took a qualified Electrician to build control systems with good old relays, timers and contactors. Unless you had good knowlege of the relevant regulations how to wire safety systems this is a task that would be seldom attempted by a novice. Most Electricians moved on to PLC control with ease because they had a good background already.

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Aye!
My boss want's me to teach our new apprentice PLCs cause "he's goon on computers" but as i told him; I would much rather teach one of the older apprentices that knows whats going on outside the PLC, but is not that great with computers.

just look away.......

yeah its a problem, but until emplyers ask for and require a proper certification for these jobs none will be neede.

I would be in favor of a license even. At least pass a test somewhere take a class official apprenticeship something.

This barrier to entry would weed out the non logical types and be a great way to add value to those doing the work legit.


If there were such a system I would join and be certified.

I almost took the CET test just to do something, but I never had time and no one ever asked for anything beyond an interview.

I have this thought between jobs frequently but then I get on with the next project.

Just imagine what it would do to our saleries if the non tech types were all booted?

Why do car mechanics need a certification but industral techs do not?

They work on a machine that you depend on for the safety of maybe 12 people if we count the ones you might run over. I have worked on PLCs that could kill over a hundred if things went wrong and poison thousands.

And the only time I have brought this up it was seen as a "rant". Maybe I use the wrong words or mention it at the wrong times.

Anyway this is not a popular issue with the masses.

dahnuguy said:

I would be in favor of a license even. At least pass a test somewhere take a class official apprenticeship something.

This barrier to entry would weed out the non logical types and be a great way to add value to those doing the work legit.

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I respectfully disagree. Licensing would help a little, but I don't think it would significantly alleviate the problem. I work with a great many licensed professional engineers that aren't worth a diddle.

Someone who is book smart can pass the test but not have the common sense, mechanical instincts, or process understanding to properly and safely program an automation system.

I don't have a good solution, but the best practicable one appears to me to start with the school system and have the instructors stress real world applications and safety considerations.

yeah I mixed in 3 things.........

Tom Jenkins said:

I respectfully disagree. Licensing would help a little, but I don't think it would significantly alleviate the problem. I work with a great many licensed professional engineers that aren't worth a diddle.

Someone who is book smart can pass the test but not have the common sense, mechanical instincts, or process understanding to properly and safely program an automation system.

I don't have a good solution, but the best practicable one appears to me to start with the school system and have the instructors stress real world applications and safety considerations.

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You dissagree with the strangest things and in ways that lead me to believe you never understood the statement you are disagreeing with.

A system of education is part of the issue , a certification or license is part of the issue, weeding out the ones who are not right for the job is part of the issue, but until the employer requires something, none of it matters at all.

To drive legaly one is required by the state to take and pass a basic test and carry a license from the state.

This system does not prevent idiots from driving but it does leave a trail and a history of their offenses.

There are a long list of jobs that require some certification or license but any body with a PC can have a shot at PLC programming.

In the "old days" of relay programing the problem was less frequent because the work was work.

Now every new college grad is looking for a job that uses a PC and is in some air conditioned space. Thanks to progress? allot of jobs are going that way.

I have sat in a plant on a bucket beside a machine where it was loud and frequently 140 degrees F on the floor with all sorts of offending odors and moving objects for hours on end, programing a PLC. The field service engineers who came after me would never do such a thing. One in fact discovered the 50 foot limit of rs232 by trying to connect to a machine from the break room. He would look at the machine for an hour and then go to a room with AC and move bits around and try it again for a day or 2 and then they would call someone else to go "help" them.

I have learned from my insane curiosity and my need to find out why. I must find the problem, I have to. It is a compulsion. But I would have been much better if I had some structured course or apprentiship.

This is one thing I like about the Germans. Maybe the only thing.

But there has to be something that separates someone who is honestly on the course to doing this job and someone who is just playing around.

I lost an arguement with a engineer about the MCR and Estop issue.

He used the Estop as an input to the PLC and then used the PLC to stop the machine.

I argued that the Estop should control the stop condition directly and ALSO be an input to the PLC so the control knows why thing have stopped and can do a reset.

I lost this arguement.

They contacted OSHA and got the OK to do it their way. Or thats what I was told.

Even when you have standards they are followed when it is easy to follow them and then the result is covered up.

Anyway some system some safety some something....................what we have is close to nothing.

dahnuguy said:

You dissagree with the strangest things and in ways that lead me to believe you never understood the statement you are disagreeing with.

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I think Tom understands and I agree with Tom. The problem is what would you test? All PLCs are different and program differently or have different networking capabilities. I would not even put PLC questions on the test. I think it is more important to get certified to work on a particular type of machine rather than the PLC. PLC knowledge should be a given. There is MUCH more to programming than scaling an input or output or figuring out how to toggle an output.

A system of education is part of the issue , a certification or license is part of the issue, weeding out the ones who are not right for the job is part of the issue, but until the employer requires something, none of it matters at all.

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The employer is responsible for training on his machines.

To drive legaly one is required by the state to take and pass a basic test and carry a license from the state.

This system does not prevent idiots from driving but it does leave a trail and a history of their offenses.

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Yes, but an employer can check that too.

A PLC is like a hammer. Framers use hammers to pound nails. It is important to pound the nails quickly but that is just the grunt work. Programming is like being an architect. The architect must make sure the whole house or building is sturdy.

We have a term at Delta. It is "high tech ditch digging". This is what we call the grunt work that engineers do. For instance "connecting the dots" on a board layout. Kids are trained from an early age to connect dots in their coloring books. The CAD programs can "connect the dots" for you if you let them. The big difference between a board designer and a computer or unskilled person is that the board designer will know how to "connect the dots" in the optimal way so that trace lengths are minimized or kept the same length. Analog and digital lines are kept apart. High frequency lines are kept in the inner layers etc. There is the bigger issue of picking the right chips and knowing what dots to connect. The point is that just because you can use a CAD program to layout circuit boards doesn't make one a board designer. The same goes for PLCs. A PLC is just a tool like the hammer and CAD software.

So just because a framer is certified to pound nails, that doesn't qualify him to design houses or buildings.

Think i am gonna chime in based on 20 years in safety where I closely worked with Facilities groups and from 40 years (off and on) as electrician.

E stops functions
1. supposed to be used only for emergency
2. shut whole machine down
3. place it in mechanical zero energy state.
4. Upon reactivation (?) ie pull the E stop back out is not supposed to restart the machine all by itself (very very common)
5. Supposed to kill power to the PLC inputs and outputs.
6. The exception to 5 is where PLC (and or VFD) is needed to accomplish zero energy state ie bleed off cylinder on punch and place ram at bottom.
7. After 6 is done then power to PLC input and outputs is killed (along with VFD)

I am doing this not to be the guru but to make double dang sure I understand this whole thing.

As far as the other stuff here are my thoughts
1. CERTIFIED means you paid the class tuition and were there at end to get the certificate.
2. LICENSED means you had the money and finally passed the test.
3. TRAINED almost same as #1.
4. QUALIFIED somebody said you know what you are doing
5. DEGREED you were able to take all the classes, pay the tuition and remember enough to pass the test. I know -- I have an AA BS and MS.

The above are pretty pessimistic definitions I admit. But the proof of the pudding from the above is when you investigate an accident. Yes they have all the paper required but they still screw up
- part of this admittedly is from being human - we are never I am afraid going to eliminate this aspect.

COMPETENT means you really know what you are doing and also what you do not know and find out before you really mess up. It also means you test your work for proper operation before the work can be called done.

Dan Bentler