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 Post subject: Requirements for Operating Disconnects & Circuit Breakers
PostPosted: Tue Jan 06, 2009 10:37 am 
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I understand the requirement for a Qualified person to check out a tripped circuit breaker. I do not understand if the new NFPA 70E-2009 or previous versions require anything special to simply open local disconnects for motors or to operate disconnects in motor control centers. I also wonder how it affects Panelboards. I am talking about existing equipment so it generally wouldn't be "arc rated." Any ideas?


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PostPosted: Mon Feb 02, 2009 3:20 pm 
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All versions of NFPA 70E have been very coy in posting requirements and not stating how those are to be met. I believe they want ALL persons operating electrical equipment to be qualified for that equipment. That might include lightswitches, for which the employer is now responsible to train and QUALIFY the workers for such duty. :(

I sincerely believe the authors of NFPA 70e would advise that even purchasors of domestic power devices be qualified before being allowed to purchase hairdryers, and toasters.


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PostPosted: Mon Feb 02, 2009 6:46 pm 
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Gary B wrote:
That might include lightswitches, for which the employer is now responsible to train and QUALIFY the workers for such duty. :(


Hmm, read the 70E about 100 times, never saw that in there, please state article.

Gary B wrote:
I sincerely believe the authors of NFPA 70e would advise that even purchasors of domestic power devices be qualified before being allowed to purchase hairdryers, and toasters.


Really? You sincerely believe that? What made you so bitter?


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PostPosted: Mon Feb 02, 2009 6:51 pm 
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Mark Daily wrote:
I understand the requirement for a Qualified person to check out a tripped circuit breaker. I do not understand if the new NFPA 70E-2009 or previous versions require anything special to simply open local disconnects for motors or to operate disconnects in motor control centers. I also wonder how it affects Panelboards. I am talking about existing equipment so it generally wouldn't be "arc rated." Any ideas?


Depends if you have done an analysis or are using the tables. Chances are for a panelboard the analysis will show there is not an arc flash hazard and the panelboard would be marked HRC 0 requiring only non melting fabrics to be worn by the operator, which is a good idea anyways. If you are using the tables it specified what needs to be worn. I guess i am looking for a more specific question from you, maybe I can help more.


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PostPosted: Tue Feb 03, 2009 7:58 am 
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Mark, In addressing the situation of non-qualified persons operating disconnecting means, Local disconnects, MCC Disconnects, Breaker operation on-off action in panel boards, cord and plug connected equipment (of large scale 30 amps-200 amps at 480 volts three phase) i considered OSHA 1910.331-334, and NFPA 70E 110.6(D)(2). individuals operating electrically equipment have some potential of being exposed to electrical hazards. some part of a good overall electrical safety program could or should include training for the non-qualified persons covering the hazards and the limits of their interaction and operation of disconnects, breakers, industrial cord and plug connected equipment. One recent example of how non-qualified training may of helped, was in a recent trade magazine (i will try to find the article and send it to you) where non-qualified persons used a 2 X 4 to stop the bolt lock type switch from tripping, i'am sure if solicited we could get hundreds of stories like this? for my situation i have a large number of operations personnel (non-qualified) who by job assignment have to operate electrical equipment i.e. breakers, disconnects, etc. We are in the process of devleoping some trainning on electrical saftey.


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PostPosted: Thu Feb 05, 2009 9:26 am 
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Zog wrote:
Hmm, read the 70E about 100 times, never saw that in there, please state article.

Really? You sincerely believe that? What made you so bitter?


Please keep your assessments of my disposition off this forum. In addition to being dead wrong such comments of yours have zero potential to contribute anything constructive.

My comments are based on the inclusive yet vague wording in NFPA 70E, and some of the (OSHA) documents that refer to it. I'm sharing how I've seen these affect a liability-concerned large industrial plant. I am presently editing a safety standard that includes training for anyone operating anything electrical. That's not my personal interpretation, but the company's based on their committee having reviewed this standard.


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PostPosted: Thu Feb 05, 2009 10:30 am 
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Gary B wrote:
Please keep your assessments of my disposition off this forum. In addition to being dead wrong such comments of yours have zero potential to contribute anything constructive.

My comments are based on the inclusive yet vague wording in NFPA 70E, and some of the (OSHA) documents that refer to it. I'm sharing how I've seen these affect a liability-concerned large industrial plant. I am presently editing a safety standard that includes training for anyone operating anything electrical. That's not my personal interpretation, but the company's based on their committee having reviewed this standard.


You are right, i should not assess your disposition, and I apoligize for that,but my point is not wrong, but your comments on the scope of the 70E were misleading to the OP, and a flat out exageration.


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PostPosted: Thu Feb 05, 2009 1:59 pm 
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Zog wrote:
You are right, i should not assess your disposition, and I apoligize for that,but my point is not wrong, but your comments on the scope of the 70E were misleading to the OP, and a flat out exageration.


It is not an exageration that the place for which I am reviewing an electrical safety standard, has in their best judgment after reading NFPA70, decided that everybody entering the facility shall recieve 'some' electrical safety training, even the secretary's that only need to operate a light switch. For nontechnical staff, this training amounts to little more than telling them NOT to switch things they have not been company trained to switch. But this training is documented. This is a large international company well stocked with technical and legal staff. We can bicker whether or not that was the intent of NFPA70E but hey, they are the customer and that is their interpretation. That they have come to this interpretation indicates the scope of 70E.


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PostPosted: Fri Feb 06, 2009 4:06 am 
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Hi Everyone,
Yes 70E can be open to a wide range of interpretations. I don't think it was intended to be so vague in some places but they sure did a good job at leaving some areas wide open.

Two interesting developments over the past 2 days. An NFPA 70E committee member mentioned just Wednesday that the intent was not to include light switches and small stuff but to include the larger equipment like 600A enclosed switches (which is the size he mentioned) except I'm sure he did not mean 600A is an official cut off it was just an example. There is no official list of what is included and what is not which makes this a real problem.

The intent, which is not at all clear, is to include circuits with a lot of power which creates the hazard (someone needs to define what that is :eek: ) At a presentation he did, he pointed out many conflicts and confusing areas within 70E (I think we have hit on quite a few of them in this forum).

His suggestion which has been posted here a few times is for all of us to pitch in and make proposals for changes to the language and wording. The changes come from all of us.

I'll be the first to admit I'm guilty of not being happy with some of the 70E wording but I'm also not doing much about it so I guess that means I should step up to the plate.

I have seen some companies have a short electrical safety training session for all employees. I guess this goes along the lines of training I had years ago when I worked for a large utility. Now and then they had an all inclusive training session on anything from trip and fall to frostbite. <<(Northern Ohio - minus 4 degrees yesterday)

The light switch seems like a stretch except.... I got home from the IEEE 1584 and ESW conference last night, went upstairs, flipped on the hall light and the switch popped, sparked, then the lights went out in the hallway.

Pretty sure it was just the switch so I guess things can fail. - except it was low power and not much of a hazard. Guess what I get to do this evening? Where's my screwdriver and voltmeter! :mad:

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