Can someone explain what's going on in this panel? (Pic included)

Discussion in 'Electrical Forum discussion & Blog' started by PM5K, Feb 14, 2008.

  1. PM5K

    PM5K New Member

    Messages:
    154
    Location:
    San Antonio, TX
    I've looked at how panels and subpanels are normally setup and the one I'm looking at doesn't really look like anything I've seen, possibly because either:

    I haven't seen enough panels to know what I'm looking at

    It's older and wired differently

    It was done wrong

    Or maybe even some other explanation

    I am posting a picture, I'm not interested in what's coming out of the right side knockout, that goes to a light fixture.

    Now here is what I see, four wires come in from the bottom of the panel, one I assume is the neutral wire which is connected to the neutral bus, there are three other wires, one connects to the top of the right side breaker, which is then jumped to the left side breaker (I don't know if that's how it should be done) and the other two wires come from the bottom of each breaker.

    Can anyone explain to me which wires do what if possible?


    [​IMG]
  2. hj

    hj Moderator & Master Plumber Staff Member

    Messages:
    27,032
    Location:
    Cave Creek, Arizona
    box

    It appears that the right hand wire is the hot feed and it is feeding both breakers from the top. The bottom wires are the ones to the fixtures or whatever is being controlled by the breakers. The white wires are the neutrals. Not a particularly same installation, unless there is a primary breaker in another box limiting the current load on that common hot feed. Otherwise you potentially have twice as much load on that one wire than it is supposed to carry.
  3. Chris75

    Chris75 Electrician

    Messages:
    608
    Location:
    Litchfield, CT
    All I see is a bunch of code violations... :D Looks like they fed the panel with 120v.
  4. PM5K

    PM5K New Member

    Messages:
    154
    Location:
    San Antonio, TX
    That's what I thought, what confuses me though is that there is a neutral coming in, but I don't see one going out, only two hots?


    Also, those two breakers in that subpanel power six outlets and two outdoor lights, and five interior lights, there is of course a breaker in the main panel for this subpanel, it's a 20 amp I belive.

    Other than the obvious problem with the jumper wire, I think there is something else wrong with this setup, it used to work and as far as I know it worked this way for quite a while.
    Last edited by a moderator: Feb 14, 2008
  5. PM5K

    PM5K New Member

    Messages:
    154
    Location:
    San Antonio, TX
    I did a little more digging and this is what I came up with:

    There are two seperate sets of two wires coming into that subpanel, the first is the hot which connects to the top right breaker and the nuetral which connects to the neutral bus on the top, there is also a ground but it was cut back and not connected to the subpanel.

    There are also two wires together that are both connected to the bottom of each of the breakers which go to the outlets , basically HJ was correct.

    I was confused by this, what makes sense to me is that hot and neutral come in, and hot and neutral come out, one from the bottom of the breaker and one from the neutral bus, just like the wires coming out of the subpanel from the right that go to the light fixture.

    I tested the two wires that connect to the bottom of each of the breakers and one has continuity with the ground on the receptacle and the left blade of the outlet, the neutral wire also has the same continuity, while the other wire only has continuity with the right blade of the outlet.

    It almost seems like the one that shares the continuity with the neutral wire should have also been connected to the nuetral bus, but I'm probably wrong, especially considering the fact that at some point some of the outlets worked, I can recall at least two that used to work, and as far as I can recall the other four or so never worked.

    The only other thing I can come up with is that those two hot leads exiting the subpanel have a nuetral from the main panel that's not connected here in the subpanel.

    Can anyone explain how this setup works, and what alternatives I should consider?

    TIA
    Last edited by a moderator: Feb 14, 2008
  6. PM5K

    PM5K New Member

    Messages:
    154
    Location:
    San Antonio, TX
    So after a bit of looking this is what I've found:

    The hot and neutral connect to the house underneath in a junction box.

    This junction box is right in the middle and the neutral splits, one to the front and one to the back, and then one to the subpanel shown in my original post. The hot goes into the subpanel and then of course goes back down from the bottom of each of the breakers, one to the front and one to the back.

    I don't know the whole story yet on the ground but some of the outlets are grounded and some aren't, I'm not totally sure why just yet.

    So here's what I was thinking, I already have another subpanel that's about three feet above the one shown in my original post, I want to disconnect the incoming hot and neutral and run a hot and neutral from the new subpanel down to the junction box underneath the house.

    I guess the only real question is if I can add that much to the subpanel.

    As it stand now here is how the subpanel looks:

    [​IMG]

    The top left is for a 240 volt outlet, the top right is for another 240 volt outlet, both are 30 amps, the first one on the bottom is for one 110 volt outlet, and the bottom one is unused, both are 20 amps.

    The run from the main panel is one of those double poles and says 60 amps.

    I want to add two twenty amp just like the original subpanel, I already have one unused so I just need one more, or I could remove the one outlet from the 20 amp and use that one, I'd like to keep the one outlet if possible.

    So I'd have two new 20 amp breakers, I'd connect one hot to the breaker, one neutral to the neutral bus and then run those wires underneath the house and connect them to the hot and neutral for the front, and do the same thing for the back.

    Any thoughts?
  7. Bill Arden

    Bill Arden Computer Programmer

    Messages:
    584
    Location:
    MN, USA
    I see a corrosion problem.
    1. The box is corroded.
    2. The jumper wire is corroded and looks like it failed.
    3. The left upper breaker has corroded and failed.
    4. The neutral bar is corroded.

    Physics violations. (I don't know code)
    1. upper right wire passes under the screw twice.
    This can cause the wire to break off or fail.

    If it would be me... (more code violations follow)
    1. pull the breakers and connectors out of the panel
    2. replace the neutral bar and top breaker screws.
    3. Clean the Neutral bar and breaker pieces using a acid and then water and dry.
    4. Apply an anti-oxidant like you use in AL.
    5. rewire it the way it was except run the wire in the upper left in a U shape to prevent the wire from going under the screw.

    But most importantly... Find the source of the moisture that caused it to fail.

    Edit: I just noticed that the box lacks both a ground and wire protection as it leaves the box.
    This makes it dangerous as the metal box itself could become hot and hurt someone.
    Last edited: Feb 15, 2008
  8. PM5K

    PM5K New Member

    Messages:
    154
    Location:
    San Antonio, TX
    I think that's good advice, but that's really the last thing I'd want to do, mostly because of all of the things you've mentioned, I'd rather either use the other subpanel, which is wired exactly as you'd normally see it, with very thick gauge wire, grounds, the regular style breakers you see almost everywhere, etc.

    But, if for some reason it's better to keep this subpanel, I'd rather replace it entirely with a new one rather than try to fix it, especially since as you mentioned, the left breaker failed, it also melted some of the plastic on the subpanel itself.

    TIA
  9. Bill Arden

    Bill Arden Computer Programmer

    Messages:
    584
    Location:
    MN, USA
    If you can run wires back to the larger sub panel, that would be better and a lot quicker.

    It looks like you might have to use a tandem breaker since the label indicates that the bottom two positions are not usable.
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