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sepefrio
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John...at quick glance I see a couple of concerns:

One is that, unless I'm color blind, there seems to be a couple of black conductors connected to the bottom of the right ground/neutral bar. Do we know what they are for?

The second, and maybe more important, is the two-pole 40-amp breaker (2nd down at left) appears to be wired with undersized solid strand aluminum.

Oh yeah...there is the lack of an insulated grounded/neutral feed. Unusual, but I'm not so sure that would be wrong in this particular case or not. Is that 4/0 SE cable?

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Besides double lugging @ the two black wires @ the neutral bar, I would think that they would be wrapped w/white tape... just as the white wires @ the top double 20's are wrapped w/black tape.

If I could get my hands in that panel, I would be curious if the switched color wires originate from the same circuit, and then if they do, why the switch.

With all the copper in that box, why the aluminum?

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Hi,

Is it a main or a sub-panel?

With nearly all of the grounded conductors on one bus and the equipment grounding conductors on the other, at first blush it looks like it's configured to be a sub-panel. However, it's fed by a 3-wire SEC, the neutral and ground buses are bonded together with that back strap and there is a bonding jumper between the right-hand bus and the enclosure, as well as a heavy solid service grounding conductor at the bottom left connected to the left bus, and I suppose that SGC is connected to a grounding electrode someplace, so I guess it's supposed to be a main panelboard.

Since it's configured as a main, the two grounded conductors added to that left bus with all of those EGC's really don't matter. The black wire that's connected to the right bus, which Richard mentions, has a white stripe on it, so I guess it's identified as a grounded conductor. Still ok if it's a main panelboard and would be fine if it were a sub-panel (as long as the bus weren't bonded).

I do agree though that those look like two aluminum hot leads connected to that two-pole breaker that Richard mentioned. If the breaker is marked cu/al, I wouldn't be concerned about the aluminum wire. I disagree with Richard, though; that looks like #8 aluminum conductors to me, in which case it's correct for a 40 amp load. I wouldn't worry about the lack of any anti-oxidation paste because that's probably new copper alloy and is not as brittle and won't oxidize like the old stuff. The paste is more a mark of good workmanship than a necessity.

That's if it is a main panel. If it's a sub-panel, it's all screwed up.

What's with the screw clamp on the SEC/Feeder where it enters the panel? I've never seen one of those done that way before.

ONE TEAM - ONE FIGHT!!!

Mike

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Mike...I'm fairly sure it should be #6 Al for a full 40-amp load. BUT...I suspect that's the AC with the conductors sized by the data plate, and probably OK.

I can probably count on one hand the number of times I've seen that sort of SEC entering a service panel with the bare wrap used for the neutral. My gray matter tells me that there isn't anything wrong with the set-up but it always has me doing a double-take. If Jim says it's OK, that's good enough for me.

So...now I'm left wondering what John and his electrician were disagreeing about.

You out there John?

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It cannot be a sub panel since it does not have a 4 wire cable coming to it. If it is a sub then it is way wrong.

Maybe he is talking about the 2 wires per terminal bar hole that has been violated.

If those black wires neutrals going to the 240 line, some white tape would be nice.

Everything else is a little too far away.

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Originally posted by Richard Moore

Mike...I'm fairly sure it should be #6 Al for a full 40-amp load. BUT...I suspect that's the AC with the conductors sized by the data plate, and probably OK.

Hi,

My chart says that a #8 is too small if it's 60 deg. C wire but that it's fine if it's 75 deg. C wire or better. Looks like 90 deg. wire to me.

I could have gotten it wrong though - I'm very weak in electrical.

OT - OF!!!

M.

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I'm guessing the disagreement is over the Alum. circuit...

Mike, the wire size for 40amp. with Alum. is #6 (over-current protection is guided by the 60 degree C column regardless of the insulation rating - See table 4-1 in Hansens book). If this is an A/C unit it may still be ok per the data plate but what I see is a four conductor cable... there is a bare ground and the insulated wire with the white stripe on the neutral side. This would be more common to an electric oven or a small sub panel which would mean it is overfused.

Of course I am going against Jim here which makes me leery... Just in case, I'm on a special diet and not allowed to include crow in my meals, so be nice.

The only other thing I can think of is the fact that the wires are all bunched together. Really nice craftsmanship but discouraged due to heat de-rating. I've never called this and likely never will.

What would be the problem with an uninsulated neutral? It's a Service Entrance Cable... No issue there.

So are we going to find out what the beef is or what?

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OK first off, I did not report this, instead like I said above, I talked to my buddy and he said not to. But it still sits in my craw. I'm probably just flat wrong or being too picky. But I thought I could post here and get other opinions and maybe an explanation better than my friends.

And to answer a few questions, this is the main, there are two 2ton 20amp A/C. The heat was gas. The 40 amp is the dryer. And yes that is a black wire with a white stripe.

First area of concern is the circled (Blue) ground wire. Notice how it goes under the circuit breakers. I think it is too close, if not in contact with the bus. Also, with it under there, are the circuit breakers pressed against it? I didn't touch it now will I ever touch a wire in the box but it made me go, Hrmmm.

The second is the highlighted wires on the right side. The green lines trace the wires to the neutral and Circuit breaker. But the third wire (the one in red) just disappears. I could not find it anyplace else. There are a lot of wires in there and maybe I missed it, but I certainly did try to find it.

Last and this may go with the above, or not, but the number of neutrals and grounds = 49 (not counting the large ground exiting the box circled in blue). There are 28 circuit breakers. My math says there should be 48 neutrals/grounds or at least an even number. My friend said I'm just being paranoid.

My big question was about the ground that may be in contact with the bus. Again my bud said no worries, if it was it would have fried something by now. BTW the sockets I checked inside the house check out OK.

Forgive me if I sound stupid, I'm just trying to make sure and maybe learn something here.

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If the two 20 amp dbl breakers, with the white wires taped black, are feeding 240 volt equiptment and do not have neutrals, only grounds... you would be left with 23 breakers and 23 neutrals. I cannot enlarge the picture to count the grounds.

The 240 volt circuit feeding the stove has a neutral (and a ground) because it is also feeding 120volts to the stove.

The 4th dbl breaker is feeding a multiwire cuicuit, sharing a neutral.

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Richard is right. That tray is physically screwed to the enclosure and the buses are isolated from the tray. There is no way for it to touch those hot buses from behind the tray.

The third wire doesn't just disappear. It bends to the right and connects to the neutral bus with the curve behind the bus tray. If you'd given it a tug near the bottom of the box you would have seen the corresponding termination move a little bit.

I count 21 single pole breakers and a couple of multi-wire branch circuits. I see 23 EGCs and 23 grounded conductors. You've still got room in there for one more breaker.

Looks right to me, but don't go by me - electrical is my weak link.

ONE TEAM - ONE FIGHT!!!

Mike

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Originally posted by sepefrio

. . . First area of concern is the circled (Blue) ground wire. Notice how it goes under the circuit breakers. I think it is too close, if not in contact with the bus. Also, with it under there, are the circuit breakers pressed against it?

It can't touch the bus from there. It's behind the panel plate. The busbar is attached to a black plastic mount that's on top of this plate. The wire you're concerned about is between the "panelboard" and the enclosure. That's probably not the best place for it, but it's quite safe there.

The second is the highlighted wires on the right side. The green lines trace the wires to the neutral and Circuit breaker. But the third wire (the one in red) just disappears. I could not find it anyplace else. There are a lot of wires in there and maybe I missed it, but I certainly did try to find it.

I think it's the one at the very top of the neutral terminal bar. If you want to trace these wires, you've really got to grab hold of them and gently lift them up & down. Otherwise it's impossible to see where they really go. I don't recommend this though. You ought to be able to do a perfectly acceptable inspection without touching anything in there.

Last and this may go with the above, or not, but the number of neutrals and grounds = 49 (not counting the large ground exiting the box circled in blue). There are 28 circuit breakers. My math says there should be 48 neutrals/grounds or at least an even number. My friend said I'm just being paranoid.

Have we forgotten that some of the 240-volt circuits might not have a neutral?

My big question was about the ground that may be in contact with the bus. Again my bud said no worries, if it was it would have fried something by now. BTW the sockets I checked inside the house check out OK..

Next time you're in the evil orange box, check out the (probably miswired) display panels to see why that isn't a problem.

Forgive me if I sound stupid, I'm just trying to make sure and maybe learn something here.

Don't apologize. Asking intelligent questions is how we all learn.

- Jim Katen, Oregon

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If the equipment ground was 'touching' the hot bus somewhere, it would have tripped-off the breaker for the circuit that the equipment ground is connected to instantaneously (if the breaker was 'good' and all the proper connections for that circuit and the panel had been made). That is why equipment grounds are 'bonded' to the panel enclosure. You must really 'go to town' in panels that are really nasty!

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