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NFPA 79 and UL 508
5

NFPA 79 and UL 508

NFPA 79 and UL 508

(OP)
   I have dealt with NFPA 79 for several years , but now I keep hearing about UL 508 for panel building.
    Could someone please explain the difference between the two? Does this mean all components should be UL listed or do they have their own standard , like IEC and NEMA standards?

Thanks for your help!
Afterhrs  

RE: NFPA 79 and UL 508

Suggestion: The NFPA is not legally obligated for the product safety. It is legally obligated for the product safe operation and maintenance. The manufacturers of products are obligated to adhere to industry standards, e.g. UL 508 at a question. The panel builder should adhere to UL 508. However, since there is the product application also needed after the product sale, the manufacturers foresee the product adherence to NFPA safety codes. Therefore, it is prudent to follow not only the industry standards but also the safety code related to the product after it is sold and installed. There is where the safety suddenly becomes important at the product and at the product manufacturing environment via the product tech support. Some products do not sell much since they are posing a safety concern, e.g. cars with the dangerous gas tank location.

RE: NFPA 79 and UL 508

UL508A is the standard used for panels by a large section of industry. The NFPA, I believe, assists in the requirements of the panels but UL is the testing agency that performs testing or approval of the panel. If this is a fire control panel then NFPA will also have to approve the panel by way of a field inspection.
Not all components need to be recognized or listed. But if they are not, you may have to perform additional testing. If they are all listed or recognized then you still may have to perform testing, there is no guarantee by using all UL listed or recognized components. In any case, if your a panel builder you build several panels and have them checked by UL (usually at your location) and eventually after great expense they will allow you to approve the panels yourself (almost). You still have to get the test report approved from UL. The UL link above will help alot. The relevant standard is UL508A. (the components you use in the panel are likely recognized or listed under just UL508)
(listed part can be used as stand alone devices, recognized require additional considerations when installing, one example is a device that requires a certain connector be used or fusing before the device; these are only a couple of examples and it varies widely by device)

RE: NFPA 79 and UL 508

(OP)
   Thanks to all for replying!
   After reading the link above link I will continue to use NFPA 79 only. UL508 doesnt cover the whole machine, just the panel. I have seen plenty of machines wich have 10 motors and several junction boxes.
   My main duties are as an MRO electrician ,but I am sometimes called upon to retro-fit and upgrade a panel
or engineer, design, and build one from scratch.
   I just wanted to make sure I was not completely missing the boat on a new standard.
   Maybe I should call it "MROB" the B will be for build.

Regards,
A.H.         

RE: NFPA 79 and UL 508

NFPA 70 " The National Electrical Code " an enforceable document when enacted it to law by the AHJ "Authority Having Jurisdiction" local electrical inspector.
This code contains provision that are considered necessary for safey. Atricles 90-7, 110 require that all materials must be third party approved ie UL,CSA,ETL, etc. Using a listed devise of the open type and installing them in an enclosure requires the assembly to be third party labeled.
The though being that the inspector, inspects installation for code compliance, not equipment. The inspector opens the door on the equipment and observes the label as per Article 90-7, if present he is confident that the equipment meets the requirements of Article 110. The cost of becoming  a
UL 508A panel is much lower than paying for a UL Field evaluation. I Know we have this equipment all over the country ... but when the AHJ enforces Article 110 then what.
Also what about the user insurance carrier requirements?

RE: NFPA 79 and UL 508

REDDOG is correct about responsibility lines.
Electrical inspectors cannot possibly be responsible for knowing if components are correctly applied, assembled, etc.

Therefore, the best inspectors will require third party certification.  They just look for the lable, write down the serial number, and they then check for proper connection of the electrical supply and grounding, then they are done.  Anything inside is wrong the panel builder and UL are responsible for.

Also, be careful.  Many panel builders and equipment manufacturers claim UL, and they can put the label on, but they do not claim that everything they build is UL, and then they will not put that UL sticker on anything unless you are looking and demand it.  Very common practice.  We have noticed lately that many of the biggest companies in the world are doing this.  All advertising claims UL, then when you get the product, not UL.  Oh, you wanted UL?  That is an option.

PUMPDESIGNER

RE: NFPA 79 and UL 508

(OP)
REDDOG AND PUMPDESIGNER,
     I have to say you gentleman bring up some valid points,
however, I do not agree with them completely. Let me explain
why.
    1) I have been dealing with a company that has been in business for over 100 yrs and always produces a top notch
machine electrically and mechanically.I have never seen a UL
certification on their panels. These machines are built very
high standards.
    2) When I do have to build a panel "in house"  you can believe it is with top shelf, UL listed items. The problem is I work for a tier one automotive supplier, not a panel build company. So basically you are saying that it is becoming mandated that I use a UL listed panel build company and not take on these projects and save the company a substantail amount of money ,even if I have the ability to do the job right and meet or exceed all codes and OSHA regulations . I definitely do not like that.
    3) UL 508 does not cover the whole machine, so the panel can meet the strictest standards only to have the rest of the machine electrically "hacked" together. I definitely believe the inspectors are being lulled into a false sense of security on this point.
    4) Electrical inspectors, this is where I think the heart of the problem lies. Most, not all,but most inspectors gain all their experience in the commercial and construction end of the business and have very little experience with industrial machinery. Thus, having a UL gives them a way out and once again, a false sense of security. When an inspector shows up on the scene to take a look at new a
facility, I know that they that will take a look at more than just the main switch gear, most will look at all the bus duct, transformers, lighting panels, and grounding. I believe they do this because the are alot more familiar with and know the code alot better in the construction  arena.
    6)My last point, after reading what PUMPDESIGNER had to say, how are inspectors are going to check to see if the the UL tag is legitimate. How many do you think will call to verify it is , or came from a UL listed panel build company.  


     PUMPDESIGNER, on a different note, I am very interested in knowing the name of the equipment manufactures you are running into UL certification problems with. As far as getting UL panels, I would put it in your electrical standards and have the company you are dealing with sign a document saying they have read your standards and compliance is mandatory. If they do not want sign it, then dont give them a purchase order and take your business elsewhere.

Regards,
afterhrs

RE: NFPA 79 and UL 508

(OP)
To add one more thing, I would say it is getting to the point where we are going to need several different types of electrical inspectors......I believe we are already there, but the industry is lagging behind.

Regards,
afterhrs

RE: NFPA 79 and UL 508

afterhrs - All your points are valid and I agree.  UL is not the only way, but the main point is Accountability.

Accountability - Just like our federal government has three departments that are a check on each other, all humans need to be accountable to others.  Third party can do that.  Another way in your situation is quality control person in design and fabrication.  You can also get into the UL508A program, costs are not high.  $5,000-$10,000 perhaps with very small reasonable charges for inspections.  And there are benefits to that spent money. I have found that our fabrication people now have someone they can talk to and be answerable to besides just me.  They have their own goals now to make sure they are always compliant and that saves me a lot of concern, they have their own relationship with quality control guy which is the UL Inspector.

Also, in lieu of UL the engineer becomes third party when he stamps a drawing with his name, and then also inspects finished product for compliance with drawings/specs, and signs for that.

Yea, people will cheat.  Interesting thing though, when you set up a system people hate to cheat and will attempt to comply if easy.  They will cheat when forced to, but that makes them nervous, tears down their business, and makes employees jittery and lose respect for their company.  Company can go downhill quick.  The competitors and employees are watching, sooner or later ...

Just recently I turned in a competitor.  UL will not divulge the consequences, but their local guy told me that the outcome will probably be a hold on their fabrication shop, they will have to pay for 100% inspection of all outgoing product for awhile.  All UL labels are removed from their possession until UL is satisfied problems are fixed (hard for people to fix their morals though).

Also, I know a guy in my industry that had UL walk away from them forever.  The owner of the company told me personally what happened.


PUMPDESIGNER

RE: NFPA 79 and UL 508

Suggestion: Any Nationally Recognized Testing Laboratory (NRTL) label will be better than nothing, when it comes to equipment that is a subject to electrical inspections and electrical safety according to safety codes, not just NFPA safety codes, but also local, state and federal rules and regulations. My statements may be used, if applicable, e.g. ships may have different requirements.
Visit
http://www.osha.gov/dts/otpca/nrtl/
for NRTL list

RE: NFPA 79 and UL 508

jbartos is very correct.  We just happen to use the UL system, but the others could be used and you never know, they could be better than UL.
But some third party as outside verification is a very good way to go.

PUMPDESIGNER

RE: NFPA 79 and UL 508

(OP)
PD and JB,
   I fully understand what you are saying about accountability. After a number of years in the military in a very technical field, I am a firm believer in holding people accountable.
   Right after I joined my current company ,they purchased a machine without getting the electrician involved. The build quality was dreadful. The company used the cheapeast
controls they could find, no wire duct, and every wire in the cabinent was black ,480vac, 110vac, 24vdc, it did not matter, the wire color was black. I had just recieved the cheap electrical version of the MODEL T.
   After this incident, it was abundantly clear that the days of people taking pride in what they do could never be taken for granted again. We have no electrical engineers to speak of, and most of our mechanical engineers are tool and die guys.
   Given these facts, I decided to take the bull by the horns and create an electrical standard for the company based on the NEC, NFPA 79, and my state run OSHA regulations. With this document I have complete and total control over all electrical specifications and components that will be used. We just recently puchased our first machine using thses standards and I am waiting for the all the electrical build specs so I can approve them.
   On the mechanical side, I would like to know what equivalent is to the NEC for mechanical standards. One of our younger engineers was given the task of writing a mechanical standard and the company we purchased the machine from had all kind of questions regarding his mechanical standards. He sort of got beat up in front of the vice president. This guy is well liked and has already done some great things on the floor. Any help you are willing to offer would be greatly appreciated.

Regards,
Afterhrs     

RE: NFPA 79 and UL 508

One note to remember is UL508A encompasses the panel as a sole product. It has nothing to do with the parts inside by themselves. So technically, none of the parts inside would have to be UL listed or recognized if the entire panel is tested and approved to UL508A. Granted, carrying UL recognized or listed parts in the panel will likely reduce testing cost and time.
There are many NRTL labs that one can use besides UL like CSA, TUV, Nemko, etc..
I think the industry understands the use of standards but the inspectors, in some cases, lack the knowledge they need to make justified decisions. Each locallity is different no matter where your at. I believe standardization (even within the states) would do great things for reducing costs. However, this day is certainly ions away so we just have to know our local inspector and how he likes to do things.

RE: NFPA 79 and UL 508

(OP)
Buzzp,
    I believe we are at the point where we may need a few different types of inspectors for the following
     1)residential
     2)commercial
     3)industrial
  OR there needs to be some type of test that inspectors have to take to qualify them in all the above areas.
   
Regards,
Afterhrs  

RE: NFPA 79 and UL 508

You guys are making great points, I have enjoyed this.

In the end, after we do the best we can, the old but true adage will always stand, "let the buyer beware".

My approach: Avoid bad people, establish relationships of trust well founded, look for trustworthy people, then have a good time !!!

PUMPDESIGNER

RE: NFPA 79 and UL 508

I agree that inspectors need to be more specialized. There is way too much to know about each area mentioned. However, this is going to add costs to state, federal, and local governments but is the only way I see to get an even playing field from locallity to locallity (except of course for the local additional regulations).  

RE: NFPA 79 and UL 508

(OP)
PUMPDESIGNER,
   You must be a great judge of character, and only deal with about 15% of the people you run into. I am to much of skeptic, but I am still working on my intuition when it comes to dealing with people.  

Buzzp,
   It will have to happen sooner or later. Unfortunately, it is going to take some of tragedy and or loss of life to bring this to the public's attention. That is our reactionary way of doing things in this country. Just look at all the attention our power grid is getting.....NOW!!!

   I agree, this has been excellent thread !!!!!

Best Regards,
Afterhrs

    

RE: NFPA 79 and UL 508

afterhrs - Pretty sharp observation about me, really.  You might be high about the 15% deal.

I fully realize that many of you guys are in tougher situations than I.  Forced to specify work in such a manner that you could beat Al Capone in court if necessary, and forced to teach Daffy Duck how to build the space shuttle because he was the low bidder.  Would almost be bearable if they had Daffy Duck's personality, but usually they have the attitude of a badger.

But there are a few great companies out there that you could almost turn your back on and they would make you look good.

I suppose that I do not like the adversarial system.  If a bad company gets the job, you got a headache, and the results cannot possibly be as good as if you get to supervise a company that voluntarily does the best they can.

PUMPDESIGNER

RE: NFPA 79 and UL 508

(OP)
PUMPDESIGNER,
   You get what you INSPECT, not what you EXPECT. This saying has helped me greatly.

Regards,
Afterhrs

RE: NFPA 79 and UL 508

(OP)
Pumpdesigner,  

    The more I think about your analogy, the more I have to laugh,unfortunate as that may be.

    Let me add a few to it, to see if it hits home.

Daffy Duck as the builder, Wile E. Coyote (self proclaimed genius) as the engineer, and finally we have Yosemite Sam wanting to blow up the machine becuse he did not follow
the operations manual.

Regards
Afterhrs

RE: NFPA 79 and UL 508

afterhrs - You make a profound statement about getting what you inspect.  I will remember that one very well.

PUMPDESIGNER

RE: NFPA 79 and UL 508

(OP)

   I would just like to say thanks to all who particapated in this thread. I have gained alot of insight.
 
   Pumpdesigner,
           I cant take credit for that saying, I learned
    it in the Navy.

Regard all
Afterhrs   

RE: NFPA 79 and UL 508

Suggestion: The electrical safety and other related type of safety are gradually becoming stricter and stricter, e.g. light curtains, duplication of safety related controlling/switching devices, etc.

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