Subpanel box wiring

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wrote:

Ok, so I spoke to the inspector today and we talked about jumping the phases and the grounding rod issue. He suggested that I put all my breakers on one phase. He said I could jumper them together, but that the connectors for the hot leads are not designed to hold two wires. He said that if I want to jumper them I would have to use a pigtail and wire cap. But he strongly suggested that I use only one phase. So I went and got a new box that has three breaker positions for each phase, which is perfect. It has a convenient screw spot in the neutral bar for bonding, so I will ask the inspector when he comes if I need to bond the neutral. I also bought the extra ground bar.
So on the ground rod-- he said I probably didn't need a ground rod, that it is debatable, but if it were his shed, he'd do the ground rod. The reason is that he would use one is because if there is ever a power surge that originates from the shed (IE lightning) that the #10 wire wouldn't be able to carry much. It has to carry the surge all the way back to the ground rod at the house. If there is a ground rod at the shed then it won't have to go all the way back to the house.
I pointed out to him that if the ground rod is there and is causing RF problems or tripping my GFCIs that all I have to do is disconnect it.
I didn't get a chance to ask about the floating neutral, sorry. He was in a hurry, so I got cut short.
I'll post some pics tonight.
Oh, also, about the loads I'm going to have on this: I have one circuit that will be running some occasional woodworking tools, like bandsaw, chop saw, drill press, etc. Occasionally I might run a router on it, but I can do that up at the garage if it trips breakers. It would be rare, at any rate. I have another circuit that will run some lights-- two flourescent lights over my work bench, a small ceiling fan with light and one light outside over the door. The final circuit only has two recepticles-- one for a small, window air conditioner and maybe a dorm fridge on the other.
Thanks for all the great advice on this!!!
John
It sounds like NEC is not this inspector's strong suit
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Honestly, I'll have to agree. I had already spoken to him once before and had asked how deep I needed to bury my wire. He said something like 6" for conduit and 18" for UF. I was pretty sure that wasn't right, but I didn't know for sure until later. I think it was just a slip on his part. Like maybe he was distracted or something... But he's been there for a while, so I don't know what to think.
John
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Ok, I apologize for being so slow on this, but I've finally got photos:
http://tinyurl.com/65s22f
Saturday I installed the conduit on the back of the house. I've got the UF trench running underneath my screened-in porch, ending next to the crawlspace door. It comes up the wall from a riser of 3/4" PVC and into a 4x4 box. The 4x4 is where I connect the UF to the THHN (or whatever it is... I can never remember), which runs in the conduit across to my main breaker box. I've got the ground and neutral wires connected in my home breaker box, but the black is wire-capped and hanging loose. I've not yet gotten a breaker for it.
I've installed the ground pole near the shed and connected it to the ground bar in the shed's breaker box. I haven't bonded the neutral to the box. I don't think it is called for in this situation, but I left the neutral bonding screw in a plastic bag in the box in case the inspector says I need it. All connections are made in the shed and I think I am ready for rough-in inspection. I'm planning to clean up a little and call inspections on Tuesday.
Enjoy the pics and thanks!
John
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Thanks for sharing. Not too bad for an amateur. Everything looks neat. Generally you don't leave the cable jacket on in the electrical panel more than 1/4" or so. Usually a different clamp on the ground rod is used for direct burial. We call them an acorn style ground rod clamp. The type that you used is for water pipes. The ground wires in the switch box are kind of short and not spliced properly. There are green wire connectors available with a hole in the them for making a splice on the grounds and bringing one pigtail out through the hole. Additional grounding pigtails come out just like any other on the bottom of the connector. I noticed that you didn't splice the #10 hot wire so that you can feed the other half of the panel. Do you have the metal ceiling box grounded with a green 10/32 screw? All of your grounds should be spliced correctly for rough inspection.
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Correct-- the other half of the panel is dead.

No, I was planning to do that when I installed the fixture, but it is easy enough to add.

All of the grounds are spliced using the crimp connectors.
I am surprised that the crimp-style connectors would be considered incorrect. I always thought them superior to wire nuts. I would have used standard wire nuts except on the advice of an experienced electrician.
Thanks for the tips!
John
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wrote in message

Correct-- the other half of the panel is dead.

No, I was planning to do that when I installed the fixture, but it is easy enough to add.

All of the grounds are spliced using the crimp connectors.
I am surprised that the crimp-style connectors would be considered incorrect. I always thought them superior to wire nuts. I would have used standard wire nuts except on the advice of an experienced electrician.
Thanks for the tips!
John
The crimp style connectors are acceptable, I didn't see them in the photos. To me the wires just looked as though they were twisted around each other. The ground wires also looked a little short. Code calls for all conductors to be long enough to extend at least three inches past the edge of the box. Ground the metal box before you get your rough inspection as that is one of the things the inspector will be looking for.
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Thanks for the tips. I guess I should add that not only am I an amature, but this is my first time doing this. I've had a mentor that has done this many times helping me, though. He also helped me dig the trench and run the final bit of conduit to the breaker box.
On the ground wires in the switch box, they are longer than they look. They are pointed at the camera. But I find it surprising that using the crimp connectors would be considered "improper" for the ground wires. I used the crimp connectors to splice all of the grounds on the advice of a fairly experianced electrician. They strike me as being superior to wire nuts.
No, I didn't splice the two phases of the panel together as the inspector said I would be fine just using one leg of the panel.
I didn't use the green ground screw on the ceiling light thinking that I would wait until final, but, now that you mention it I believe that would be a mistake.
Thanks,
John
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Very lovely! You definitely don't use the bonding screw. The one thing I see is that you cut your grounding conductors in the switch box to short. They need to be attached to the switches
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The ground rod needs to be at least 8' in the ground, so if that is an 8' ground rod, it should be fully buried. If it is a 10' ground rod, then you are OK with part sticking up as you have.
Cheers, Wayne
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Hi Wayne,
It is an 8' rod, but I've got it to where the top is now flush with grade. I've dug out around it a little so I could attach the connector and have not backfilled it so the inspector could see it. So If I wanted to install a second rod, would I just jumper the connection from the same ground wire?
John Grabowski:
The ground wires are a little longer than what they look in the photo. They are pointing at the camera, so the look shorter. But they may not be long enough to meet code, so I will check. I will also install the ground screw this evening.
Thanks for all the help, fellas!
John
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If you want to install a second rod, you can clamp the jumper to the first rod or to the grounding electrode conductor (the ground wire going from the first rod to the panel). Be sure all the clamps you use are rated for direct burial, for both the jumper and the grounding electrode conductor.
BTW, if the rod is your only grounding electrode, you need to install two. [There is a provision for installing only one in the NEC, but it requires a measurement of the effectiveness of the first rod that is way more difficult to make than installing a second rod is.]
Cheers, Wayne
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ACTUALLY, if your going to stick with the code..... the grounding conductor should be all one piece and go from one rod to the next.
s
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On Mon, 4 Aug 2008 12:47:23 -0500, "Steve Barker DLT"

Not true, it only needs to be un spliced to the first electrode
From the handbook
http://esteroriverheights.com/electrical/ground.jpg
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NOT what the NEC says. but you the boss.
suit yourself
s
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On Mon, 4 Aug 2008 15:24:47 -0500, "Steve Barker DLT"

Steve, you are confusing THE grounding electrode conductor which goes to "any convenient electrode" unspliced.
250.26(F) To Electrode(s). A grounding electrode conductor shall be permitted to be run to any convenient grounding electrode available in the grounding electrode system or to one or more grounding electrode(s) individually. The grounding electrode conductor shall be sized for the largest grounding electrode conductor required among all the electrodes connected to it.
Subsequent "bonding jumpers" between supplemental electrodes and be made up with any listed connecting device as long as it remains accessible.
250.68 Grounding Electrode Conductor and Bonding Jumper Connection to Grounding Electrodes. (A) Accessibility. The connection of a grounding electrode conductor or bonding jumper to a grounding electrode shall be accessible. . Look at the picture again. That is from the NEC handbook
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look at 250.64(C) and get back with me.
s

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On Aug 5, 12:03am, "Steve Barker DLT"

I found an interesting article on it here:
http://tinyurl.com/6ax6oc
If you skip to the section on splicing I think it addresses the topic at hand. I might be way out in left field, too, I don't know. This is all very new to me.
John
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On Mon, 4 Aug 2008 23:03:54 -0500, "Steve Barker DLT"

OK I'm back. The GEC is the conductor to the first "convenient" electrode. The rest are bonding jumpers. I already gave you the cites
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OK then. it sounds like an area for easy misinterpretation.
s
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On Tue, 5 Aug 2008 05:16:57 -0500, "Steve Barker DLT"
No sweat. I would not be surprised if lots of inspectors are confused. I did get my interpretation from IAEI seminars. They are usually worth the money if you get a chance to go to one. Jim Pauley is the gold standard. He puts on the best show.
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