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Discussion Starter #21
what is the issue about the phone and satellite line to shed will that be a problem if i run 8-2 rather than 8-3 or i just cant run them near each other
 

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Hello tity04

Your picture shows a meter main with feed thru lugs which I am assuming is serving a panel in the dwelling on a 4 wire feeder using a insulated equipment ground so it is possibly modular home or permanent mobile home.

You do not change anything in that main panel.

The separation of neutral and ground is only done in the sub-panel in the shed. Since you have other conductive paths due to low voltage cables going to the shed you must run a 4 wire feeder to be code compliant. Other conductive paths are in parallel with the electrical supply to the shed and may become energized in the event the neutral would open in a 3 wire feeder and beaker would not be able to trip in this case. 4 wires allows fault current to return to the source via the added ground wire in the event of a open neutral and a breaker will trip to clear any faults. Also neutral current would flow on the other conductive paths if they are bonded to a 3 wire installed panel for grounding purposes. So you must separate the ground and neutral at the shed to keep neutral current utilizing the feeder neutral only.

The diagram I have attached shows how it should look. You will simply install a double pole 40 amp breaker in your main panel. Connect the red and black of the uf-b #8 to the breaker and the bare and white to the neutral bar. You need to come into the meter main thru a 3/4 or 1 inch knockout for that size cable.

Your sub-panel is main lug however code requires a disconnect. It looks like you have an 8 space 16 circuit sub that is main lug. My opinion is you should have a main breaker in that panel or a back fed double pole with hold down kit or a separate disconnect rated at least 60 amps ahead of the shed sub-panel attached inside or out side very close to where you bring the uf-b into the shed. Using what is called the six hand rule is in my opinion not compliant for a detached building. However your inspector may allow it. It simply means that the total number of single pole and double pole breakers installed in the panel cannot create more than 6 movements of the had to shut them all off. Essentially killing all power to the shed. If you have 7 movements of the hand you must install a main.

Now 8 awg copper uf-b is good for 40 amps so that will be your feeder rating. It needs to be buried 24 inches deep with protection where ever it is exposed to possible damage. You will purchase a ground bar that will install in those two hole on the right side of your shed sub-panel. this will bond with the metal of the sub-panel when you use the mounting screws supplied with the ground bar. Make sure it is the proper GE ground bar that will correctly use the two holes that are pre-drilled in that panel.

Do not install the green screw in the neutral bar or whatever came with the panel to bond the neutral bar to the metal of the breaker panel. If it has been installed by the factory ....remove it. You do not want the neutral bar bonded to the metal only the ground bar. All your branch circuit neutrals and the feeder neutral will connect to the neutral bar (left side of panel with the large lug). All your grounds for the branch circuits and grounding conductor to the ground rod will connect to the ground bar you install. the two hots of course go to the disconnect or main lugs if the inspector allows it. Diagram below click on it to enlarge. It is meant as a guide so if any questions ask. Remember there is more to this as far as a correct installation than just running a feeder. So ask questions if you need but I believe the major issues have been covered.
 

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Doesn't the sheathing of that 12/2 cable entering the box need to be cut back?
No it doesn't. The NEC only requires it to be at least 1/4" into the panel not any less... you can run it 8 inches into the panel if you want. Keeping the sheaths of the cables stipped back generally makes for a neater look and better wire management but that is all.
 

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Discussion Starter #24 (Edited)
Yes it is singlewide ,ok thanks but there will be no inspector i just want it to be safe thats why im asking question.
1. one more when i run the phone and sat cable after i put the dirt back over the uf can i add those lines about a ft or more over the uf .
2. the copper wire going to ground rod at shed is that a particular size i need.
3. if i run those other cable no where near the uf do i still need the 4 wire.
 

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Yes you can 12 " separation is the minimum. You need a #6 copper grounding conductor ran to the ground rod (s) and secured with a direct burial clamp. sometimes called an acorn clamp-----
 

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Discussion Starter #26
I tried to read through my post and dont remember me asking if i ran the 3 wire and at the shed the ground rod would that make up for the forth wire
 

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No that has nothing to do with the feeder. The UF-b will have 4 wires Red and Black hots and a white neutral and a bare equipment ground.

You need the 4 wire regardless of where you run those other cables.
 

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If he uses 3 wires and has no other metallic paths, explain to me what exactly would make it not a good installation. Electrical theory please, not an answer of "well, if it was so good why is it not allowed in the 2008 code".
Not because of the 08 code. But because we have enough circulating neutral currents as it is, we don't need any more. When we drive a ground rod and tie it to a neutral in a 3-wire feeder, we create a parallel path for neutral current. Sure, the impedance of the earth makes the amount of neutral current in the ground small, but still nonzero. This small current is finding it's way into everything it can to complete the circuit. Some of it is going back on the phone ground, some on he cable tv ground, some on the neighbors ground, and so forth.

A good install would have a 4-wire feed.

InPhase277
 

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Discussion Starter #30
Is there a major difference in the half pole breaker apposed to the full pole if they are the same amps.

Does it make a difference for ground rod copper or aluminum .the electrical place sold me the aluminum and said its only ground its not a major problem using this rod.
 

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Is there a major difference in the half pole breaker apposed to the full pole if they are the same amps.

Does it make a difference for ground rod copper or aluminum .the electrical place sold me the aluminum and said its only ground its not a major problem using this rod.
If the panel can accept the half size breakers they are OK. The only problem that I see with them would be heating due to crowding.

You surely mean a galvanized steel rod, right? Aluminum is not permitted to be used as a grounding electrode. If it is galvanized steel it is fine. Lightning doesn't care if it is steel or copper really.

InPhase277
 

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Discussion Starter #33
Sub -panel

I was told on one of my threads to add a main shut off in this panel how do i do that because at lowes they have no idea.

And besides code is there another reason bare wire need to be 24" deep
 

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Whatever size your feed is going to be (say 50 amp for example, add a 50amp breaker in here and hook your feed from the main panel to that breaker.

Not to knock the workers at places like lowes or homers, but most of them aren't really trained in electrical and only know the basics. Sometimes you come across retired guys that are very knowledgable, but not very often.



Also, I don't know if this has been pointed out or not, but the length of sheathing coming into the box in that pic of the 12AWG romex showing is a little long. It shouldn't be more than 1/4 to 1/2" inside of the panel, although I am not sure on the EXACT specs.
 

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I was told on one of my threads to add a main shut off in this panel how do i do that because at lowes they have no idea.

And besides code is there another reason bare wire need to be 24" deep
Find the panel part number and see if it can be converted to a main breaker panel. I personally don't know if it can right off hand. But often the lugs can be removed and a main bolted in place. Barring that, you can either replace the panel, or buy a disconnect switch and mount it near the panel, or back-to-back with it.

And besides code, the depth of any cable or conduit is mostly to keep somebody from accidentally coming into contact with it. It would be a shame to be working in the garden and cut into it while planting bulbs...

InPhase277
 

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Andy

NM-b cable sheathing must extend into the box/enclosure at least 1/4" not 1/4" or 1/2" and less. You can run it into the box 10 inches if you want.
 

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Andy

NM-b cable sheathing must extend into the box/enclosure at least 1/4" not 1/4" or 1/2" and less. You can run it into the box 10 inches if you want.
Okay, I must have read it wrong then, I thought it said it could ONLY BE A CERTAIN LENGTH, not that it was a MINIMUM length. Thanks.
 

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If your GE panel model# starts with TLM it is convertible to a main breaker panel.
 

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Whatever size your feed is going to be (say 50 amp for example, add a 50amp breaker in here and hook your feed from the main panel to that breaker
.

Andy

You cannot just make a blanket statement like this. The panel is configured main lug it may or may not be a convertible mains. Any panel that is allowed a backfed double pole breaker must have a retainer kit intalled. You cannot just slap in a double pole breaker and call it the main disconnect.
 
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