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    Lone Ninja's Avatar
    Lone Ninja Posts: 12, Reputation: 1
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    #1

    Jun 27, 2006, 04:25 PM
    Grounding Bar vs. Neutral Bar?
    Hello all. I have extended the wires from an unused 240 outlet to the backyard for a spa via a sub-panel. I also hooked up a new grounding electrode near it to avoid having to run a fourth wire all the way back to the main panel. This fourth wire goes to the small grounding bar in the sub-panel and from there to the spa.

    The 50 amp circuit trips instantly when I turn it on. Is this because the wire that was originally used for grounding in the outlet is still connected to the grounding bar? Should I disconnect it from there and move it to the neutral bar? Some of these bars have jumpers so what difference would it make anyway? Help...
    tkrussell's Avatar
    tkrussell Posts: 9,659, Reputation: 725
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    #2

    Jun 27, 2006, 05:18 PM
    The neutral must be isolated and insulate from the equipment ground and from the metal box of the panel. No grounds , only neutral connect to the neutral. If the 50 amp CB is a GFI,should be feeding a spa, the white pigtail needs to connect to the neutral bar. And only bare or green grounds connect to the equipment ground bar, which must bolt to the metal box of the panel.

    If this helps, great, if not some pictures will help seeing some detail.
    Lone Ninja's Avatar
    Lone Ninja Posts: 12, Reputation: 1
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    #3

    Jun 27, 2006, 05:24 PM
    Thanks for the quick response! In the sub-panel the two bars are separated and the pigtail is going to the neutral bar from the GFCI 50 amp for the spa. And I have the ground connected as you said.

    But I suspect that my problem lies in the Main Service panel not in the sub-panel. So in the Main Service Panel should I move the third wire that is not hot from the ground bar over to the neutral bar? Now that it is serving as a neutral wire in the rest of the connections.
    tkrussell's Avatar
    tkrussell Posts: 9,659, Reputation: 725
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    #4

    Jun 27, 2006, 05:34 PM
    You got me on this one, which wire is not hot? The neutral from the sub panel? Any mis wire here may cause the GFI CB to trip, but I would like to get more detail.

    If the main breaker is located at the main panel, the grounds and neutrals all connect together, sounds like you do not have a main breaker in the main panel.
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    Lone Ninja Posts: 12, Reputation: 1
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    #5

    Jun 27, 2006, 05:48 PM
    I sorry for the confusion, I had very detailed post and then did something stupid and lost it. So here I am re-writing it.

    Prior to my mettleing, there was an electric range in the kitchen. It was later upgraded to gas. This outlet has a 50 amp CB in the main service panel that operated just fine on last check. That 240 outlet was not being used so I replaced it with a junction box and ran the wire to the backyard. Once in the back yard I added a sub-panel with a 50 AMP GFCI for the spa. Now the spa requires four wires and I only had three from the outlet (two hots and one bare to ground the original outlet). I installed a new fourth wire and hooked it up to a new grounding electrode and to the spa's ground via the grounding bar in th sub-panel.

    When it didn't work I realized that I have wired what was being used as the grounding wire in the outlet (the bare one) to act as the neutral wire for the spa. So if I am right the power is trying to return to the power source via the "neutral" wire and since it is still connected to the grounding bar in the main it trips the CB.

    So my solution is to (in the main) disconnect this bare wire from the grounding bar and move it to the neutral bar in the main in order to complete the circuit. What do you think?
    tkrussell's Avatar
    tkrussell Posts: 9,659, Reputation: 725
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    #6

    Jun 27, 2006, 05:58 PM
    Sounds like you are using the bare neutral as a ground also, or have it connected wrong. The bare wire of a three wire SEU cable is neutral, and not a ground, esp if the unit feeding it feeds needs a speaparte ground.

    And this wire should not touch any ground before getting back to the neutral bar, which can happen easily in junction boxes, etc. This cable is used for circuits that allow for the neutral and ground to be connected together , and is not used for GFI's.

    You may need to run a temporary ground wire, or neutral to show that this cable may need to be replaced with a four wire cable.
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    Lone Ninja Posts: 12, Reputation: 1
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    #7

    Jun 27, 2006, 06:01 PM
    Thanks again for the response. I'll check it out again tonight when I go home and let you know what I find.
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    Lone Ninja Posts: 12, Reputation: 1
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    #8

    Jun 27, 2006, 10:45 PM
    Okay, I looked at it again and it seems to be connected up the way it's supposed to be. Originally, when the three wires were hooked up to the outlet I'm sure that the third bare wire was being used as a ground.

    Now that I have extended the wires to the backyard I wired that third bare wire to function as the neutral for the spa. I installed a fourth wire to a new grounding electrode and it goes through a grounding bar that is connected to the sub panel box and does not touch anything else.

    The problem is it's not working (I thought you'd like that). But after I looked at it again tonight I noticed that my main service panel has only bar. This bar is the grounding bar and the neutral bar. I don't get it, obviously I'm missing something but how can the neutral bar also be the grounding bar. What's to stop the current flowing back on the neutral wires from going to the ground instead of where it should go?

    So if the panel has a grounding/neutral bar what difference does it make if it it's touching the sides of the junctions box or elsewhere? I still need to check and see if it is touching the junction box just be sure. But I'm just getting real frustrated, can you tell? I'll try and post some pics soon.
    tkrussell's Avatar
    tkrussell Posts: 9,659, Reputation: 725
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    #9

    Jun 28, 2006, 02:47 AM
    Yes please if you can furnish pictures of the main panel, the sub panel, and the connect at the spa will be very helpful. I want to see you have this wired correctly, and grounding is very important to a spa.

    I understand your frustration, but need to be patient to get this right. Neutrals and grounding in panels can be confusing.
    tkrussell's Avatar
    tkrussell Posts: 9,659, Reputation: 725
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    #10

    Jun 28, 2006, 02:47 AM
    Yes please if you can furnish pictures of the main panel, the sub panel, and the connect at the spa will be very helpful. I want to see you have this wired correctly, and grounding is very important to a spa.

    I understand your frustration, but need to be patient to get this right. Neutrals and grounding in panels can be confusing.
    Lone Ninja's Avatar
    Lone Ninja Posts: 12, Reputation: 1
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    #11

    Jun 28, 2006, 07:52 AM
    Okay, here are some pics I just took:

    The Main Service Panel:


    The Sub-Panel:


    The Span Connections:


    The Diagram from the manual:


    The only deviation from the diagram is that I made a new ground nearby instead of running a fourth wire back the main.
    Thanks again.
    tkrussell's Avatar
    tkrussell Posts: 9,659, Reputation: 725
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    #12

    Jun 28, 2006, 02:04 PM
    OK where do I begin... before I get to the ground/neutral wiring, I will list a few items I see that are done improperly,bear with me...

    All cables enter the main panel through a couple of knockouts at the top, and one cable at the bottom. I have to believe this is the way you found the installation done. Did the installer forget what cable connectors are? The cables can rub up against sharp metal edges ,which can cut into the insulation and cause shorts and sparks. Any sparks created can get into the walls and created a smoldering fire. Whoever installed this service or wired this home should have his license pulled. What a mess. They saved about 10 dollars not using proper connectors on each cable.

    There is one cable at the bottom that shares one pole of a two pole 30 amp breaker. The breaker terminal is only rated for one wire. Hard to tell, hopefully the wire is #10, if #12 then the wire is only rated for 20 amps then is over fused at 30 amps. This wire should be on it's own breaker.

    Sorry if I offend you, but I can tell by the subpanel installation it was done by a DIY, I am going to take this opportunity to list the defects to help others at the risk of offending you:

    Wiring is not run in the panel neatly in a workmanship like manner, sheathing left on the cable.

    Locknuts missing on the 2 " PVC connectors... bushings that cannot tighten down to the metal do not take the place of locknuts

    This is a serious condition if true:
    Each aluminum wire terminations in main panel, subpanel, and spa terminal strip appears to be missing the required anti-oxidant compound,which will prevent the exposed aluminum from oxidizing,which will cause the connecctiuon to create heat and possibly start a fire. This is the only issue with aluminum wire that gives aluminum wire a bad reputation.

    Hard to tell, how is the ground bar bolted to the panel backbox? I see it appears to be hovering away from the metal over a knockout and does not looked like it actually is bolted, with a machine threaded screw. Note, sheetmetal screws are not allowed.

    The meter/panel contains the main breaker, so the neutral bar is correct with all the white neutrals and grounds connecting to it. This is only true for main panels with the main breaker in it. Subpanels are treated differently, the neutral bar is insulated and isolated from all grounds, and all grounds connect together and the metal of the panel.

    The gray feeder cable appears to be round, meaning that it should have a black, red, white, and the bare. If it is only three wire with black, red and bare, then it must have been twisted a bit from it's normal flat shape to appear to be round and I am mistaken.

    Now the issue of the GFI breaker tripping. The breaker is responding to a ground fault that should be in the tub, and I do not believe the neutral/bonding is causing the breaker to trip.

    To try to troubleshoot this situation, you may need to disconnect the feeder wires from the spa terminal strip, keep them all clear from each other, and see if the breaker still trips. If it stay on, then there may be a problem with the spa internal wiring. I suppose the breaker itself could be defective also.

    My observations:
    The subpanel issue with no equipment ground and using a ground rod is allowed by code. I would not treated this as a subpanel installation, not used a ground rod, and would have installed a ground wire back to the main panel. In the true sense of the code, I cannot argue this issue, you are covered by code in this respect.

    However, the manufacturer's instruction, which must also be considered, clearly shows a separate equipment ground wire back to the main panel. Code states that all manufacturer's instructions be followed.

    In the event there is a problem in the future with this tub, and a factory rep that inspects the unit can use the lack of equipment ground as a reason to not cover any warranty/defect or product liability issue.

    I certainly hope this helps some, but you will need to do some troubleshooting to determine what is causing the breaker to trip. If you get some results and want to get back with them I can help you decide what the next step is if you are not able to go any further.
    Lone Ninja's Avatar
    Lone Ninja Posts: 12, Reputation: 1
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    #13

    Jun 28, 2006, 04:55 PM
    Holy Wirejobs Batman! No offense taken at all, I came to this board for some help and clarity and that's what I'm getting -Thank You!

    As for the Main Panel, what you see is exactly as I found it after removing the cover. I'll work on getting another CB so that wire can have it's own. It looks like it was a quick job to get some power into the garage.

    I'll see what I can do to get some anti-oxident on that wire but I'm sure I will ultimately run a fourth wire so it matches the diagram exactly.

    The ground bar is connected to the back with one of the two screws provided with it. I will add the second screw later, time permitting. I know, I know I'll do it this weekend for sure.

    The gray cable actually is round and not flat. I matched exactly what I found in the outlet, there is only three wires on it the black the black/red and the bare. I left the cable sheath on it to have some kind of insulation on the bare wire.

    As for my other screw-ups I'll be fixing them too for sure. Right now, I want to get the darn thing up and running -safely.

    I'll do the troubleshooting that you suggested and let you know what I find.
    billy1st's Avatar
    billy1st Posts: 1, Reputation: 1
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    #14

    Nov 19, 2011, 08:34 PM
    I think how it goes is that the main service panel has the ground and neutral connected together, after that as in a sub panel the neutral and ground must be on their own bars not connected together! Is that right?
    tkrussell's Avatar
    tkrussell Posts: 9,659, Reputation: 725
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    #15

    Nov 20, 2011, 05:17 AM
    The neutral and equipment ground only connect at the Main Panel if the Main Breaker is in that panel.

    Many times the Main Breaker is at the meter, there the neutral and ground is connected, and NOT at the Main Panel.

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