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 Post subject: NFPA70E/IEEE1584 Collaboration
PostPosted: Tue Oct 02, 2007 7:43 pm 
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I am curious what people think about the NFPA70E/IEEE1584 Collaboration.

The actual NFPA70E members and IEEE 1584 members and the public are only informed formally (press release) by the chosen few who work on the collaboration. I think the collaboration has 9 people and the information is only shared with the few companies that sponsored the collaboration financially.

This seems un-American and socialist. I am concerned that the results will favor the few companies, etc. that are involved. It is not good that the IEEE is offering its technology up to the highest bidders & special interests. IEEE is a scientific organization; not a government agency.

What can we do? What do you think? :confused:

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PostPosted: Thu Oct 04, 2007 5:20 am 
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I am in support of the collaboration.

The current standards are a bit haphazard in the way they are represented. By that I mean that the 70E is not very clear in the methods to calculate arc flash energy, with appendix D listing, (if I am reading the thing correctly) three different methods of calculating the arc flash energy and boundary, one of which is from a method (Doherty) that predates the 1584 method. A collaborative effort will (hopefully) lead to more comprehensible explanations there.

The effort must get funding from somewhere. The 1584 tests were also largely paid for by industry participants, and many of the current limiting protective device equations resulted. (I generally don’t like these, because they don’t agree with the full equations, however.) The results from the original 1584 testing also was not available to those outside this effort until the end, if at all. The original test data is difficult to get.

If the collaboration does what it says it will do, and these results are also turned over to the 1584 (I don’t see why they wouldn’t be, since IEEE is a sponsor) then the end result should be a set of comprehensive physics based equations that everyone has access to, much like the 1584 equations and calculation method.


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PostPosted: Thu Oct 04, 2007 6:32 am 
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NPFA70E/IEEE1584 Collaboration

I think Michelle's comments reflect the feelings of quite a few people on the IEEE1584 committee. She is also a member of this committee and is quite involved with it. It is interesting that you pointed out that 70E is not very clear about which methods to use for calculating arc flash energy and the boundaries. At the last 1584 meeting that I went to a few weeks ago, someone stated that NFPA 70E does not endorse 1584 and therefore they publish multiple methods. A few people quickly jumped on that comment because the 1584 equations (although not perfect) are based on the best info that we have and you would think they would want to support it rather than rely on older 1st and 2nd generation efforts and equations.

Some of this stems from what I view as a political “turf war” between the two organizations (I won’t go into details publicly) so it is good they are finally collaborating - even if it is behind closed doors with a secret handshake etc. otherwise both groups would continue going in their own directions. They do need to raise a little more than 6 million dollars for this collaborative effort (testing and research isn’t cheap) and right now have between 2.5 and 3 million. So for better or worse, corporate sponsorship plays a big roll but hopefully does not bias the tests. The frustration is sometimes seen at the committee meetings where we hear ”XYZ tests occurred but we can’t share the results right now” I am confident the test results will ultimately be made available to the committee so we can begin work on writing the next revision to the 1584 standard. The new tests will include all sorts of things such as DC testing (just completed) arc blast, gases, arc duration and many things that we are all scratching our head over.

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PostPosted: Sun Oct 28, 2007 11:29 am 
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It would seem beneficial if the two committees would cooperate, concentrating on making the methods and techniques consistent and clear for the most commonly encountered commercial and industrial systems, rather than spreading the resources over every possible electrical system.

Just my opinon......

(If either committee seeks real-world feedback I can give you plenty. Here are a couple comments:
1) Hot work permit mandate is optimistic for many sites. I would not expect typical commercial electrician to ever do this.
2) Arc flash calculations indicating a 1200' arc flash boundary are not credible. Applying a 2 cycle clearing time limit 'because a worker can move away during such period' is not a credible adjustment.

I could expand this list if I go back to previous work completed)

Gary B


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PostPosted: Thu Nov 01, 2007 12:46 pm 
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Ground fault clearing times?

Jim,

You probably know this, so I am asking you. In the next 1584 revision, will ground fault clearing times be used at all to calculate incident energies? Zero sequence devices will trip on either an imbalance or neutral current, so it seems likely that they would cover both phase-to-phase and phase-to-ground faults. Heard anything?


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