panel pic

[Chad Fabry]

When a ground becomes a current carrying conductor?

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[ghentjr]

Not sure what your question is? The white wire on the upper right breaker should be marked with black. But if the panel is a sub panel then it is not properly wired.

[randynavarro]

Perhaps it's the black #12 (I think that's the size) wire on the upper right where the vinyl jacket has been stripped too far and almost, if not already, touching the bus?

Or maybe its the fact that it's probably a sub-panel and the ground / neutrals aren't isolated.

[Chad Fabry]

There is no neutral.

[kurt]

What's the silver wire @ the upper right?

[randynavarro]

Yes. I thought the bare aluminum stuff at the upper right is part of the 3-wire feed, no?

[Neal Lewis]

Originally posted by randynavarro

Yes. I thought the bare aluminum stuff at the upper right is part of the 3-wire feed, no?

It appears to be a 2 wire feed. 2 wire + ground.

[Richard Moore]

Originally posted by Chad Fabry

There is no neutral.

Yeah, but you only have the three 240-volt circuits (none with neutrals). Assuming they haven't hooked up some appliance incorrectly and they are just feeding pure 240-volt equipment, I don't see where there would be any neutral current to pass along the bare conductors. I'm not saying that you should wire a sub that way, but I'm not sure there is actually anything dangerous going on...at the moment.

Someone comes along and sticks in a 120-v circuit with a single pole breaker or a 4-wire 240-v circuit...then we would have problems.

[StevenT]

I think I see a ground hooked up, and since the black and white wires are both hooked up to a double breaker, I say that it's a 220/240 circuit, which would have no neutral. It would be nice if the white wire was wrapped with black (or red) tape.

Now that I look at it again, I'll tell you what I find strange. Since you looked at it in the "flesh" there may be something I don't see.

I see that the panel is being fed from the left side into what looks like a 50 amp breaker. OK so far... one feed to each bus. But it appears that the lugs/bus's on top are jumped to each other. If this is so, my question is, how is that possible?

[Brandon Chew]

I see that the panel is being fed from the left side into what looks like a 50 amp breaker. OK so far... one feed to each bus. But it appears that the lugs/bus's on top are jumped to each other. If this is so, my question is, how is that possible?

I started typing a reply several posts above yours. I was following the wires until I hit that jumper. Then my brain froze and my head exploded.

[StevenT]

I'm wondering if the panel is not being fed from the left and it only appears that the top lugs are jumped. I do see a ground coming from the top.

Chad, could you clarify?

[hausdok]

That's not what I see. I see three wires feeding that cable from the top; two hots and a neutral. The neutral bar on the right is bonded to the enclosure with the strap and a green screw. The neutral cables from that cable connected to the two-pole breaker on the left and the two pole breaker feeding that 240-volt plug to the left of the panel are sharing the same bar with the equipment-grounding conductor of that NM connected to those paired 20-amp breakers on the upper right and the grounded conductor was never properly marked to identify it as a hot wire. I don't see any "jumper" Steven, can you point it out to me?

It looks like if any of those hot wires were to loosen up that the enclosure and that EGC will end up being hot, no?

By the way, for those who aren't aware of it, put your cursor on the photo and click it and it will be enlarged for you.

ONE TEAM - ONE FIGHT!!!

Mike

[StevenT]

Hi Mike,

The "jumper" that I thought I saw ... appears on top, at the two lugs. But now that I see the ground, I'm sure that it is not a jumper. It must simply be two feeds that are bent and look like a jumper. If the pic was not cut off on top, I would be sure.

I don't see any neutrals. Since I don't see EMT or BX, I'm assuming that they are all grounds.

Since this is not a main, the neutrals and grounds should not be bonded together.

I'm thinking that this panel is strictly wired for 220/240. I see an outlet for a welding machine, maybe this sub is to hook up some additional 220/240 machinery.

[Chad Fabry]

I'm thinking that this panel is strictly wired for 220/240. I see an outlet for a welding machine, maybe this sub is to hook up some additional 220/240 machinery.

Sorry to be so elusive, guys. I've been grouting tile all day.

Every circuit is a 240 circuit from the sub and each circuit feeds a machine motor so thats OK..right? The problem is each machine has a built in 120 volt work light. I'm guessing the difference in the current draw on the two legs must be going back via the ground wire to the service equipment.

[StevenT]

Just like a clothes dryer or electric stove who's element runs on 220/240, but has controls that operate on 120, there really should be a neutral. Now if you are only running a light bulb the size of a Xmas light, does it really make a difference? I would say technically it still does, but it is such a little draw that it may not be an issue.

I don't see how the difference would be transferred to the ground.

I'm curious as to what the others feel regarding this issue.

[hausdok]

Whoa!

My mistake. I don't know what the hell I was daydreaming about when I called those bare wires neutrals. Replace every place I called them neutrals with grounds. Sorry.

Sometimes my brain does weird stuff. When I'd typed it, I'd called the danged bars "buses," had caught it, gone back in and changed it. Guess I was too focused on that to realize I'd called them neutrals.

I swear, I'm going to start stocking up on Depends; I'm definitely going to need them at this rate.

Still, you don't feel that box will go hot if one leg of one of those feeds to the 240 receptacles loosens? Won't that stray current then return via the grounds to the enclosure? Maybe I'm overthinking this - I hate electricity; it's too much like math for me.

ONE TEAM - ONE FIGHT!!!

Mike

[StevenT]

On any box, if a hot lead feeding the box gets loose and touches the enclosure it will get hot. As far as a leg getting loose from one of the circuit breakers, if it were 120, no. But since this is 240, if one leg gets loose it can still carry current being back fed.

I would still like an answer as to the "urgency" of a neutral, since the machinery still has 120 being used.

Is Jim on vacation?

[Richard Moore]

The built-in 120-volt worklights are "interesting". I don't know if there would be another way of doing that (like 2 lights in series?) without using the ground as a neutral. Everything in my workshop that I have hooked up to 240 only required 2 hots and a ground, but none of them have a worklight. So...I'd want to know what the required wiring feed to each machine was.

Chad, what were the machines? Oh...and full wiring schematics would help!

[hausdok]

Sounds like the situation where you have an electric stove. The burners are 240 but the clocks and other stuff are 120 volts.

OT - OF!!!

M.

[Jim Katen]

Originally posted by StevenT

On any box, if a hot lead feeding the box gets loose and touches the enclosure it will get hot. As far as a leg getting loose from one of the circuit breakers, if it were 120, no. But since this is 240, if one leg gets loose it can still carry current being back fed.

I would still like an answer as to the "urgency" of a neutral, since the machinery still has 120 being used.

Is Jim on vacation?

I'm here but I'm kind of mystified about why this picture seems to have generated such confusion. It's a 240-volt panel with no neutral. The circuits connected to it, apparently, have 120-volt loads.

Each of these circuits should have four wires and the panel feeder should have four wires. The neutral should float.

- Jim Katen, Oregon

[StevenT]

So, you agree that the panel is wired wrong. There should be a neutral for the 120, regardless of the minimal amout of draw.

[Jim Katen]

Originally posted by StevenT

So, you agree that the panel is wired wrong. There should be a neutral for the 120, regardless of the minimal amout of draw.

Sure.

- Jim Katen, Oregon

[Sodapop]

Subpanel should have been fed with a 4 conductor SE cable. ( 3 ungrounded, 1 grounded)

Each line should be phased, not according code just personal preference. Insulated neutral tied to neutral busbar. Seperate grounding busbar should have been installed. No bonding of neutral busbar to panel since it's a subpanel and ground and neutrals need to be isolated.

If posible, have a new feeder run to subpanel and install properly.

[Jim Katen]

Originally posted by Sodapop

Subpanel should have been fed with a 4 conductor SE cable. ( 3 ungrounded, 1 grounded). . .

Hmm, don't you mean 2 ungrounded, one grounded and one grounding?

- Jim Katen, Oregon

[Brandon Chew]

Originally posted by Jim Katen

I'm here but I'm kind of mystified about why this picture seems to have generated such confusion. It's a 240-volt panel with no neutral. The circuits connected to it, apparently, have 120-volt loads.

Each of these circuits should have four wires and the panel feeder should have four wires. The neutral should float.

- Jim Katen, Oregon

Yep, I got all that. Like Steven, when I first started looking at it, I made an initial assumption (because the pic was cut off at the top) that the bus bars were jumpered. If they were jumpered, feed would be from the lower left but as I followed the way the current would go in that arrangement, I realized the assumption about a jumper was either wrong or that power had never been applied to the panel. Once I had figured out there was no jumper I knew what was going on. About that time, Steven posted the comment about the jumper and I chimed in with my exploding head comment.

Chad, I'm wondering how many conductors the manufacturer called for on those machines. If those were 120V work lights and not 240V, I bet it was four...or was this a DIY motor & light wiring job?