Safety Controller

[tomP]

As to why the EL is restricted from the Safety Controller AT MY SITE:

Rule 1 of Computer Security: If you don't control the hardware then you don't control anything.

Rule X of Computer Security: If more than a handful of people can read the data then it's open to the world. If more than a handful of people can write the data it's a scratch disk.

Although circumstance modifies those two rules somewhat they are generally true. NFPA79:2007 requires restricted access to the write portion of the Safety Controllers. Therefore once the number of people gets past a dozen it is very questionable whether you are in violation.

Okay, so you have a business say that has 2 EE and 5 EL. They all have access to write the safety controllers but no one else in the place does. IMO you have met NFPA79:2007.

In my building I have 100+ ELs. If they require special access to something then their supervisors will have to know it to give it to them. Another 25+ people then have access. Of course the EEs who are responsible for the program will end up knowing it - another 15+ people. Then there are the MEs who may be around and just want to be helpful. The jobsetters that are competent. And the bathroom wall. All because BY CONTRACT if I give access to a single EL in my plant then ALL ELs have a right to get that access.

I totally understand where you are comming from, now how about us 70+ electricians and no EE no ME,
except if we place a request for one and wait 'till one gets there usually measured in days not hours.
Should we just refuse to touch anything or should we learn the ins and outs of it, as we always have done?

 

[petersonra]

I totally understand where you are comming from, now how about us 70+ electricians and no EE no ME,
except if we place a request for one and wait 'till one gets there usually measured in days not hours.
Should we just refuse to touch anything or should we learn the ins and outs of it, as we always have done?

I vote to wait for someone competent. I do not think this is a good place to be engaged in trial and error education out on the plant floor.

 

[tomP]

I vote to wait for someone competent. I do not think this is a good place to be engaged in trial and error education out on the plant floor.

Where did I say trial and error on the plant floor?
We, as I have stated, require our company train us fully in any and all new technology.

This is why I'm asking questions before we ever get any safety PLCs.

I also stated we would like to make an informed decision before the time we start getting any on the plant floor.
This decision would include who "handles" this equipment. This decision will also include local management.

Who is to say the "competent" person really is competent?
Because a person has a piece of paper that does not make him competent.

I made the "Absolutely no questions asked we can and will do it when the time comes." comment out of fustration, because of the I'm better than you attitude by a poster.

We have proved our ability over and over and will not be detered by individuals who think they know all.

 

[petersonra]

The problem is going to be this.

Try and educate a lot of people in this far more complex then it appears problem that will use it only rarely (probably most will NEVER use it), or educate a few people who will use it enough to actually retain their skills.

If there is any fiddling with typical safety PLCs on any regular basis, there is a very serious problem that needs to be addressed that has really nothing to do with the safety PLC itself.

 

[weressl]

I don't believe you would be "more than glad to apologize" , you have way of not recognizing when you have offended people and when it is pointed out to you , you simply dismiss it as "misdirected".

Intended or not I also find some of your statements insulting,..

When one persons says your fat ,dismiss it ,.. when two people tell you you're fat , look in the mirror,.. when three people tell you you're fat,..time to go on a diet you're most likely fat.

You may not think you are insulting , that does not mean that you have not insulted.

In other words try to imagine how what you are writing will be perceived , it is part of communication.

"....you have way of not recognizing". I'm highly offended when people telling me what I think. (Actually I'm not, I think it is laughable.)

"...I also find some of your statements insulting.." Generalization is a way of making offensive statements without illustrating what is offensive or how it is offensive.

"...when three people tell you you're fat..". If those three are anorexic, I can still be of normal or average weight. People who have taken an issue with the statement are electricians - as best I can determine, because many people on this list hide behind vague and anonymous descriptions in their personal profile - and are protecting their perceived turf. Not a good argument. If I were to take the same tack I would have complained that they are trying to encroach on "my" turf. That is not the case.

You are complaining about offense, yet you are yourself are trying to "counterattack", instead of demonstrating were was or am I wrong by addressing the specifics. In an eye-for-an-eye world we all go blind.

As I do not intend to run conduit or pull and terminate cables, I do not expect electricians to write complex programming sequences or perform SIL calculations. Each of us has our roles and respecting each other's proficiency in the respective subject areas will provide a safe and well functioning electrical system.

 

[weressl]

The problem is going to be this.

Try and educate a lot of people in this far more complex then it appears problem that will use it only rarely (probably most will NEVER use it), or educate a few people who will use it enough to actually retain their skills.

You've addressed well the profficiency issue that is an additional problem above the skill level.

The skill level segregation occurs at the terminals of the safety PLC or any other programable or configurable device. Wiring correctness and functioning relies on the electrician and the programming on the programmer, whoever that may be. As I illustrated with the doctor/nurse example, each of those trained to perform different duties in the same area.

 

[dbuckley]

The problem isn't with PLC programming per se; on something complex enough to need a safety PLC it's working out all the possible things that can go wrong, and taking responsibility for those decisions. Theres also the question of how do you prove your programming is correct.

I would highly recommend documenting every step of the chain, so in the event of litigation you can prove what you have done to ensure safety.

 

[M. D.]

I am addressing and answering specific points and expects those specifics to be replied to, reasoned with and engaged in dispute. I think it is a disservice to take the NEC as a Bible, especially for those who do not understand the science and try to explain what the themselves do not and can not comprehend. I am not implying malice, since they can't know what is it that the do not understand.

Not condescending to some I'm sure.

 

[pfalcon]

I totally understand where you are comming from, now how about us 70+ electricians and no EE no ME,
except if we place a request for one and wait 'till one gets there usually measured in days not hours.
Should we just refuse to touch anything or should we learn the ins and outs of it, as we always have done?

Wow, 70+ ELs and not a single competent engineer within 24 hours. Your management needs a 12-step for anorexic staffing. Or maybe cause they send one they have to puke back out afterward, it's bolemic staffing.

The problem isn't with PLC programming per se; on something complex enough to need a safety PLC it's working out all the possible things that can go wrong, and taking responsibility for those decisions. Theres also the question of how do you prove your programming is correct.

I would highly recommend documenting every step of the chain, so in the event of litigation you can prove what you have done to ensure safety.

I added DBuckley's quote because there are two different aspects to this NFPA79:2007 thing. One is legal liability and the other is competence.

Although anyone can view and troubleshoot these devices, NFPA79:2007 requires that only authorized people can write to them. Note that it does not say "qualified". Whoever your local management is can serve as the authorizing agent. Just remember that the number of authorized people must be very limited and that those people become liable. This could be three special ELs at your site. At mine we must go all or nothing.

Once you get past the legal thing then you can worry about the competent thing. I would only emphasize that since this is a safety device controller that maybe, just maybe, using any old EE or EL or programmer is not a good thing. You got 70+ ELs at your site? I got 70+ "Engineers" (not all EE) at my site. I can think of 20, no 10, no 3, yeah 3 that I would trust to program a safety device I was gonna use. :grin: