Is it just me or is the degree of waffling on this topic ridiculous? Am I the only one that thinks 70E is out to lunch? They can’t even define it! I’ll bet most of them have never smoked a breaker on a high current test set either.

I’ll go out on a limb and state that electrical equipment isn’t inherently dangerous. If it was that would be an invitation to financial ruin for manufacturers and it wouldn’t be on the market. The lawyers would see to that.

So manufacturers believe it or not do address this, though maybe not to the likings of the NETA crowd. For instance for molded case breakers the standard is to exercise (operate) it once a year and do a visual inspection once a year and after every trip. This is a far cry from what NETA states but that’s a standard written by testing companies to promote excessive and ridiculous testing not necessarily supported by science. And presumably this goes back to the idea that again, it’s not inherently dangerous.

70E does not provide procedures for not maintaining equipment nor analyzing the results for improperly maintained equipment No one does. Again this is sticking your neck out there. So the idea of putting an onus on the people working on the equipment to verify proper maintenance is done is crazy talk. You do NT know that and often you can’t. You can do some external inspection but it is unrealistic to verify “condition of maintenance� but honestly hidden failures are…hidden. It’s not possible for someone working on equipment to have deep engineering knowledge in most cases. That stuff should be a condition to 70E. If you don’t maintain it, 70E does not apply.

So with that in mind a very simple list of visual inspection results. Is it tripped or off? Is there burn marks, liquids rolling out, etc.? Are there water spots or other signs of environmental contamination or physical damage? If so, it’s not normal work.

So why insist end users must perform some magic incantation to determine factors they can’t possibly determine?

Paul,

I have had issues w/ the guidance we have through 70E as well. I would also add that IMHO, some of the recommendations in NETA and 70B are outdated in terms of maintenance, e.g. 1 yr exercising requirement of MCCBs. New manufacturing techniques would seem to indicate that guidance is in need of re-evaluation.
To your point, if testing is the only way to minimize breaker failures for example, then how far do you go? It isn't reasonable to test 20A/3p breakers, esp. for large facilities.

Interested in your viewpoint,

Mike

70B-2023 supposedly has had some updating done but I have not reviewed it beyond what is mentioned in this article:

https://www.eaton.com/content/dam/eaton ... 024Xen.pdf

A lot of "shall" in there. As you might expect, questions arise as you read it, e.g. MCCB testing required down to what level/ampacity/pole(s) of breaker? At first glance, it's silly to test 20A/1p breakers, but there is no distinction between sizes, etc.

I have to admit I only skimmed the changes, but it is a bit scary. I'm not diminishing the need for maintenance but I've always thought this doc/guidance is overkill.

Mike

It is my understanding that the latest edition of 70B provides guidance for users/owners to assess the equipment and determine what tasks are to be done at what interval at each device. You may decide to injection test all breakers 400amps and larger. The key is that you are using good judgement in your decisions and can defend the Electrical Maintenance Program if an event occurs. i.e. you cannot just say we're not going to injection test or maintenance anything.

I direct customers to injection test larger breakers with electronic trip units as well as any larger thermal magnet breakers that are critical to the process or are difficult to obtain if they fail.