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-   -   Running two 100 amp main panels from a 200 amp service (https://www.askmehelpdesk.com/showthread.php?t=61569)

  • Feb 25, 2007, 10:16 AM
    tkrussell
    Yes just like I said, the bar on the left is where both the 4/0 neutral and the 2/0 equipment ground connects, along with the copper grounding electrode conductor

    Be sure to use the 4/0 neutral at the panel's neutral bar, and the 2/0 at the panel's equipment ground bar.

    The two remaining wires, should be one black and one with a red tracer, one each to each side of the breaker.

    Not using any sleeve or bushing in the knockout?

    These wires should also be in some sort of conduit as they rise out of the ground up the meter pole and into the meter box.
  • Feb 25, 2007, 10:18 PM
    mdmaynard
    Whew, long day!

    With your help the electric was hooked up, and yes I used a bushing and 2" pvc conduit coming out of the ground. Thanks for all your assistance!! And may I say thanks again!!

    We only ran into one problem and that is yet to be figured out. This is a double wide and the electric only works on half the double wide. We found what we thought was where the two halves splice together which had three different wires spliced in a box. We reconnected those but still no electric to half the double wide.

    I am going to make a separate post on this problem, as I am not sure how to trace where else the two halves connect back together.

    Thanks and thanks again so much for your assistance. Just a note to others 4/0, 4/0, 4/0, 2/0 is hell to manipulate :-)
  • Feb 28, 2007, 06:22 AM
    Bulldog1
    Quote:

    Originally Posted by mdmaynard
    Greetings!

    I live in a rural country area. The electric company will be installing a pole, meter, and 200amp service with disconnect at pole. (It will require 50 foot run of service cable from pole to main load center in mobile).

    Currently the double wide has a General Electric 100amp Main Load Center. This is not going to be enough as I plan on changing the gas hotwater heater, the gas cook stove and the gas central heating unit all to electric. There is no more room in the existing load center.

    I have another G.E. 100amp main load center. What I want to do if possible is to install a trough and use split bolt connectors and run service wires to each of the main load center thus giving me 200 amps total. I realize I will have use torque according to mfg specs and use an oxidant.

    My twofold question is:

    1. the SER cable will be rated for 200amp, but when I run feeders from the split bolt connectors can i go down to wire rated for 100amp?

    1. Since this will not be a "main" panel / "sub" panel set up, there is no reason to have one box with neutral isolated, it can be bonded - correct?


    If I am incorrect, please advise the best possible solution to get 200amp service out of 2 100amp load centers.

    Thank you
    Martin
    In Memory of Our Daughter
    Bailey DeLonais Maynard
    January 13, 2005 - March 28, 2005
    Healing Oklahoma Hearts - Home
    S.I.D.S. It's REAL!!!

    Since there is a 200 amp breaker at the pole( most of the time), all panels after that will be subpanels. The neutral and grounds need to be seprated at the panels. At the trough you can down size to 100 amp wire to go to the panels. If the inspecting agency allows thie panels to be main breaker panels, than all neutral and grounds would not be required to on a separate bus
  • May 28, 2007, 10:47 AM
    Stratmando
    Don't know if two halves connecting problem solved. If not:
    Should be Junction underneath or behind some cover in home.
    Did both halves ever work? If so, possibly connections a panel or meter. If not, probably
    A splice Box to connect both halves, Match up letters, numbers or markings.
  • Jan 5, 2010, 07:06 AM
    mdmaynard

    Greetings all once again. I know this post is a couple years old but ran into a problem with this installation.

    January 3rd, 2010 we started having brown out and stuff that was 220 (dryer, cookstove, hotwater tank, baseboard heaters and etc.) were not working properly. I blew this off at first as something with the electric company... we had our first blizzard and temps were very cold.

    I called around and no one else was having problems. So I started investigating.

    The power pole/meter are about 50 foot from where service cable (direct buried trailer wire) enters into house panel. About half way between pole and mobile home there was a pinhole in ground with smoke coming out. I shut breaker off at meter and got a shovel to dig where there was smoke. One of the 4/0 cables of the URD direct buried wire was burnt in two.

    What would cause this to happen (no I did not put direct buried cable in any type of conduit.)

    Is it possible something in the house caused this or is it more likely from either the cable getting knicked somehow or a critter chewed it?

    FYI we had a water leak and the whole yard was flooded and when I dug there was a pool of water all around cable?

    I am going to replace this with the following and put in conduit this time:

    (2) 4/0, (1) 2/0, and (1) #4 wire for equip ground. All ran in about 3" or 4" PVC.

    But before I do I want to see if it this was likely caused by something in mobile or more likely by something else.

    I appreciate any and all inputs, suggestions, and reamings :-)
  • Feb 23, 2010, 01:13 PM
    Zornch

    Since you posted your question more than a month ago, I assume you've probably made repairs by now. It looks as though you pretty much answered your own question--the most likely things to have caused this problem are a nicked wire or chewing by a critter. Along with that, there are multiple factors. Once the insulation of a buried wire is breached, by nicking, chewing or whatever, it exposes the conductor inside to the elements. This makes it vulnerable to corrosion. If there was a sufficient nick or cut when the wiring was installed, the wire could sit for years gradually corroding until the conductor broke down to the point that it could no longer carry the current needed; that could then produce the malfunction symptoms you had before you found the problem. In addition, once the insulation has been breached you have the possibility of leakage current from the conductor to ground. That potentially could accelerate corrosion, speeding up the failure process.
    Your postings indicate that you have a fairly substantial load. Even with good wire, there will be heating of the conductor--which increases as the load increases. Once there is a developing bad spot in the wire, the higher resistance and extra heating at that spot get much worse than with the normal good wire; and the more current you draw, the worse it gets. Ultimately, it's likely that a fair amount of the smoke you eventually saw was caused by both the heating of the damaged spot and local heating of the area around it--including the leakage current you would get from the exposed conductor to ground. With the flooding you mentioned, you could have had a considerable increase of leakage current. With all that water, part of the smoke probably was actually steam.
    One of my college professors used to hand out a page giving examples of electrical problems caused by critters--including things like squirrels making a good enough path for an arc on a high voltage line; and rats or mice chewing into the insulation of buried cables. And the normal heating of the buried wires as a result of carrying current can make the wiring a more attractive target for burrowing animals, because they may be attracted by the warmth. They have no way of understanding that once they get through the insulation, they're likely to get much warmer than they had in mind.
    If you have rocky soil, it's even possible that the wiring got damaged when you filled the burial trench. That's probably a little less likely, but not totally impossible. Even the compression/pressure of traffic above a filled-in trench can occasionally help wear through insulation. That isn't usually much of a problem, but if there are heavy vehicles it becomes a bit more likely.
    A more obvious case with trenches is damaged water lines (usually crimped) caused by heavy, rocky fill just shoved back in when the trench is filled.
    Sometimes, unfortunately, bad stuff happens... Hope this helps!
  • Aug 21, 2012, 03:34 PM
    tom 0003
    You will need to put in a Junction box and the splice will be in there should work out OK. Inspectors get overly paranoid about splices if you have to shorten the conduit going into the box and add the junction box take what you cut and add it to the bottom it looks better than the wires just running in to the junction box.
  • Aug 21, 2012, 03:45 PM
    tom 0003
    My above answer was for the guy running 15' short on wire. Just an idea put some vinyl gutter over the wire before burying it that might keep any rock from be push against the wire kinking it.

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