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Nick Ostrowski
02-09-2009, 08:24 AM
Does anybody have an idea how long the maximum height for a main breaker being 6'7" has been in effect? I saw this in a 30 year old townhome. The height of the main disconnect was 6'10".

Jerry Peck
02-09-2009, 08:32 AM
The 6'7" maximum height of "any" breaker (any Overcurrent device, not just a breaker and not just the main breaker) has only been in effect a couple of code cycles ... but don't let that go yet because before then the maximum height was 6'8". The change was made to 'internationalize' the codes dimensions, with 6'7 being close to an even metric height than 6'8".

The 6'8" height goes back quite a while - I'll look in a couple of old code books and see when.

The 6'7" height was first specified in the 2005 NEC.

Prior to that, and going back as far as I checked (which was only back to 1962 as that would cover a 30 year old house) it was addressed as "readily accessible", which has been interrupted to mean (by most AHJ) 6'8". There are exceptions, of course, but none of which apply here.

Can you reach it safely and be able to properly and safely operate it while FIRMLY standing on the floor? Yes? Then that AHJ may have considered that "readily accessible", however, if you are shorter and cannot safely reach it and safely operate it while FIRMLY on the floor (both feet planted flat and firmly on the floor), then it is not really "readily accessible" is it?

I always wrote them up as being too high above the floor, took my client out there and showed them, and if they felt they would reach it safely, they let it slide (knowing that it may become a problem when they became a seller, because I told them that, and I left if in my report), and if they could not safely reach it, they usually negotiated some credit back for it (seldom did it ever get lowered - except in new construction).

In your photo, there might - MIGHT - be enough service entrance conductor to allow that to be lowered one breaker space, and the breaker under it could be moved to the lower right ... all "maybe". Granted, that would still be at 6'9", but that 1" makes a huge difference in many cases.

Is that back fed main also anchored down on the left side?

Nick Ostrowski
02-09-2009, 09:09 AM
Thanks for the info Jerry. The husband wouldn't have a problem reaching the disconnect but his shorter wife would.

As for the anchoring of the main, I'm not sure. I was standing on my toes and looking up and the sloppy routing of wires made it tough to see a lot. Plus, I had to squeeze between a fridge and water softener just to get into the area beneath the panel. Definitely not readily accessible.

Wayne Carlisle
02-09-2009, 09:38 AM
What scares me is that metal measuring tape close to all those electrical componants. Arc flash?????!!!!! Could it happen?

Nick Ostrowski
02-09-2009, 09:48 AM
Oh, I thought about that Wayne..........but I did it anyway.

Jerry Peck
02-09-2009, 10:01 AM
What scares me is that metal measuring tape close to all those electrical componants. Arc flash?????!!!!! Could it happen?

Wayne,

At some of the presentations I've done, one of my photos is pointing to what I am discussing, then I ask if anyone sees anything else in that photo ... there is always someone who, without hesitation, shouts out "That metal tape measure." - "Correct." I answer, and then add "Which is why I now use a wooden folding ruler for that, and I've removed the metal protective tip from the end of it too." :D