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Rifraf
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# Posted: 11 Apr 2012 15:53 - Edited by: Rifraf
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Ok im almost to the point where I need to get the power from my pole to the sub panel in the cabin.
My wire is more than enough, all three cables are copper 1/0
Ill be feeding from a 125 amp breaker at the pole into the lugs of the sub panel in the cabin. The run is about 60 feet.
Here are my questions.. My breaker is GE, has no + or - on the terminals, and my sub panel lugs have no + or - on them, does polarity matter on these and how can one tell the correct connection from one of the breaker terminals to the proper lug on the sub panel ?.. I did have the forethought to color code my cables with colored tape so I dont have to do any continuity tests to see which is which 
My other question is, with such a short run do I need to run a grounding rod at the cabin , or do you think simply connecting my copper 1/0 from the poles ground to the grounding bar in the sub panel is ok .
I do not have any codes to abide by, so no help from an inspector.. i just want to do it properly.
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toyota_mdt_tech
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# Posted: 11 Apr 2012 16:21 - Edited by: toyota_mdt_tech
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You will need a grounding rod at the cabin. In my area, we are required to have 2 ground rods, 6 feet apart. Can be under grade so you dont trip over them. With AC, there is no + or -, its line, line and neutral. Some call "line" hot" white neutral -. Hook each line to the input on top of the panel. Neutral to the neutral bar on the side. Grounds and neutrals will be on that.
If its a sub panel (panel from an existing breaker panel), you remove the bonding from neutral to chassis at the cabin, neutral bar is now neutral, while a seperate bar is used for grounds (you can buy a ground bar from the place you got the panel) and the ground is then hooked to just the ground rod in the ground. Not tied into the neutral.
I suspect yours would not be a sub panel, but a primary panel from the meter. So ground and neutral can be tied together??? But will still need a ground at the panel, but I suspect its in place already.
I am not an electrician, I know we have resident electricians in here who can also chime in.
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MtnDon
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# Posted: 11 Apr 2012 17:12 - Edited by: MtnDon
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Start off thinking the right colors.... black is always hot, sometimes red is hot. white is always neutral. Ground is always bare or green insulated.
On receptacles you see a brass colored screw and a silver screw. Brass is always connected to hot; the silver (think white) is always connected to the white neutral.
The AC breakers will only fit in the panel one way. One end "clips" onto the master buss (hot) and the other end has the screw for the branch circuit wire.
You say you have three wires from.... where? The meter socket or power company pole. ??? Is the service to the cabin for 240 VAC? If so, there would be two black "hot" or line wires and one white that is the neutral. In large wire sizes the neutral is usually a black insulated wire with white tape or paint at each end. 6 inches worth of marking to make it plain to see that it is neutral. In AC white is always used for neutral and never for anything else. Then depending on local regs there might also be a bare ground. That could be green insulated as well. I am not sure what makes it necessary to have a ground from where the power company left off. I've only had to deal with that once, years ago.
If there is no bare ground from supply to your panel then you need at least one ground rod, 8 ft long. It is connected to the ground of the panel.
Can you post a picture of your panel? Then one of us could maybe label where the different large incoming wires attach to. Most service panels are setup to be used with 240 VAC service. One black feeds one side of the panel, the other the other side. The neutral would have it's own buss bar to connect to. Then there would be a buss bar for the neutrals. Some panels make you buy that as an accessory.
toyota_mdt_tech mentioned a connection between ground and neutral. This is called a "bond". Only one bond should occur in a cabin/home system. When there is only one panel that is done in the panel with a special green screw that connects the neutral to the grounded chassis of the panel (the enclosure, the box). So depending on what you have where the power company stopped there may be a bond there already. ??? Hopefully one of the practising electricians will come along.
In the meantime showing us what you have where the power company stopped will be helpful.
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Rifraf
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# Posted: 11 Apr 2012 19:14 - Edited by: Rifraf
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MtnDon,
My pole has a breaker box on it, 200amp service, 200 amp main breaker above the box near the meter itself. It then has 4 open breaker spots at the pole.
Im putting in that meter box (at the pole ) a 125 breaker and from that breaker I want to run my 2 hot lines, and I have another third line for ground
These are already in conduit ran from the pole box to the cabin panel just not connected to anything yet.
There is grounding rod at the pole, and the pole is only about 60ft from my cabin.
These cables are all copper 1/0 thwn/thhn
ill see if I can dig up some still shots , but the last video i posted i think pans over it
fixed : youtube link
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larry
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# Posted: 11 Apr 2012 20:26
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@ mtndon, why do you only want to bond the main service panel and not the sub? does it make a difference? i would think that you would want all metal panels grounded so you don't fry your finger tips off if a line comes in contact with a panel..
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SE Ohio
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# Posted: 11 Apr 2012 20:38
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First off, I'm not a practicing electrician!
The advice above is good, but you might see if your GE panel (check your model number) has hookup instructions to be found on-line? Also, the nearest library or big-box hardware store will have books with pictures, diagrams, etc written for the beginner. There are more ways to do a job wrong than right, and it is worth the time to do it right and not have nagging doubts. Read over the info several times, look at other installations, and take your time, consulting the info frequently and it'll turn out right.
Review the electrical safety basics, too. Work with power off, etc. The texts should have plenty of cautions.
Another word of caution- Nothing in the panel ever needs any lube. WD-40 (a solvent) will make some panel or breaker plastics brittle!
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Bzzzzzt
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# Posted: 11 Apr 2012 20:48 - Edited by: Bzzzzzt
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Rifraf: Here is an excellent tutorial with pictures that should help you out.
http://waterheatertimer.org/How-to-install-a-subpanel.html
I'm assuming you're doing this as if it were a sub panel. The main on the pole (or wherever you are running from) should be counted as the main panel.
In household voltage, there is no + or - because that is for DC power. You are dealing with AC power. You need to make sure that you have 2 "hot" wires, 1 "Neutral" wire and 1 "ground" (or "bond") wire. It is best to drive a ground rod at the main panel where the neutral and ground should be bonded together but after that they should be separated.
I am a licensed master electrician in 2 states so if you need any further help drop me a note by removing the "at" and inserting an @...... smorkle at yahoo.com
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Rob_O
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# Posted: 11 Apr 2012 21:04
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Quoting: toyota_mdt_tech You will need a grounding rod at the cabin
Well... maybe.
Depending on who is reading the rulebook, you can say the meter panel *is* the main panel and should be grounded and bonded at that point *or* you can call the box a disconnect and say the panel at the cabin must be grounded.
In this situation I would agree with you and call the cabin panel the "main" panel and do all the grounding/bonding at that point. My compound will have the main house, a detached garage and another building or two feeding off a similar panel so I have to go with whatever the inspector says I should do.
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Bzzzzzt
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# Posted: 11 Apr 2012 21:28
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Quoting: SE Ohio Another word of caution- Nothing in the panel ever needs any lube. WD-40 (a solvent) will make some panel or breaker plastics brittle!
While this is good advice, I cant for the life of me figure out why anyone would ever spray WD-40 in a panel unless they were trying to lubricate the hinge on the cover. The stuff is also Highly flammable and electrically conductive. If you spray it into a live panel it's very likely that you'll get the living $h|t knocked out of you.
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Rob_O
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# Posted: 11 Apr 2012 21:33
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Quoting: Bzzzzzt I cant for the life of me figure out why anyone would ever spray WD-40 in a panel. If you spray it into a live panel it's very likely that you'll get the living $h|t knocked out of you.
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MtnDon
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# Posted: 11 Apr 2012 23:04
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Quoting: larry @ mtndon, why do you only want to bond the main service panel and not the sub? does it make a difference? i would think that you would want all metal panels grounded so you don't fry your finger tips off if a line comes in contact with a panel..
All metal panels/boxes have a ground. If you have a sub panel there is a hot/line buss, a neutral buss and a ground buss. The ground buss is anchored/connected to the metal case. So every case/box is grounded.
The bond though is only done once in a system. The bond connects the neutral to the ground. One time only. If there is more than one bond in the system some equipment may operate erratically. A multiple bond in the same system can cause loop currents to make strange things happen. Sometimes bad things. In a small off grid system having two bonds can occur when someone uses a cheap inverter to feed their distribution panel. Many cheap inverters have an internal neutral-ground bond. If the panel is also wired with a bond the cheap inverter frequently loses its magic smoke and doesn't work anymore. If you're close to the inverter when battery power is applied to the inverter you will hear the loud pop that precedes the loss of magic smoke.
The other reason for only a single neutral/ground bonding connection is that is what the NEC states. It is not an intuitive thing.
Don't get bonding and grounding confused with what many call the negative wire in a DC system. To many the DC negative is the ground. One's thinking and naming should be watched when talking AC and DC.
A FWIW Note: DC systems above 12 VDC should be setup with a positive (black), a negative (white) and a ground(bare or green) according to the NEC. The DC system should also have a similar bonding connection in it's main pane. In DC the negative is connected to the ground. The cabin DC wiring should also have a ground wire, easy to do if you use Romex. My DC ceiling fan has a ground lug. many DC items do not, but if any metallic boxes are used they can and should be connected to ground. I know that's off this topic, but what the heck.
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MtnDon
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# Posted: 11 Apr 2012 23:05
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Quoting: Bzzzzzt I cant for the life of me figure out why anyone would ever spray WD-40 in a panel
We could start a thread on, "Now Why Did he/She Do That?" 
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Rifraf
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# Posted: 12 Apr 2012 07:58 - Edited by: Rifraf
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Thanks everyone !
Bzzzzzt ,
That picture is what I thought I would be doing... only the electrician who set up my meter at the pole told me I would only need three lines.. so thats what I have now in the ground, three 1/0 copper lines.
Im guessing the electrician believed I only needed to run one line from ground and not one from neutral?
Thoughts on that ?
And if thats the case, do I set that little link bar in place thats in the panel or leave it disconnected ( a little bar on a pivot that seems to be connected to the breaker casing, if I spin it then it can be connected to the grounding bar on the left side) i think this is what MtnDon was referring to when he said
All metal panels/boxes have a ground. If you have a sub panel there is a hot/line buss, a neutral buss and a ground buss. The ground buss is anchored/connected to the metal case. So every case/box is grounded
In my setup im just not sure if I connect it to the bus or leave it be.
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toyota_mdt_tech
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# Posted: 12 Apr 2012 12:16
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Quoting: Rob_O Well... maybe. Depending on who is reading the rulebook, you can say the meter panel *is* the main panel and should be grounded and bonded at that point *or* you can call the box a disconnect and say the panel at the cabin must be grounded.
I agree. Main must be bonded, sub, not bonded, seperate ground bar hooked to ground rod. I also agree, meter panel can be a disconnect, while cabin can be main.
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Rifraf
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# Posted: 12 Apr 2012 12:22
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<--- blinks
speak dummy for me for just a second . I already have the three lines ran. My pole is 60ft away and has a grounding rod attached to its grounding buss.. So can I just run the three wires into my sub panel and be done ? Meaning groundbus to groundbus, and hots from 125amp breaker to the sub panel lugs ??
and do I connect that little bus brigde thingy in the sub panel ?
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Bzzzzzt
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# Posted: 12 Apr 2012 12:26
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rifraf: just use the neutral line as the neutral and ground. It'll work fine. Bond them together in the panel and then keep them separated from there.
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Rifraf
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# Posted: 12 Apr 2012 12:54 - Edited by: Rifraf
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Thanks, that's a relief !
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Rifraf
Member
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# Posted: 12 Apr 2012 13:19
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not sure if it matters, I didnt have any still shots of my panel but I ripped a few as best I could from my videos.
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toyota_mdt_tech
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# Posted: 12 Apr 2012 14:08 - Edited by: toyota_mdt_tech
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Quoting: Rifraf <--- blinks speak dummy for me for just a second . I already have the three lines ran. My pole is 60ft away and has a grounding rod attached to its grounding buss.. So can I just run the three wires into my sub panel and be done ? Meaning groundbus to groundbus, and hots from 125amp breaker to the sub panel lugs ?? and do I connect that little bus brigde thingy in the sub panel ?
rifraf, from the sounds of it, you will use it at a main panel. Run the 2 black wires to the breaker inputs (line 1 and line 2 or the "hots" and the neutral to the ground bar. Also drive in a 8 foot copper clad ground rod, tie it to the ground bar also. Leave the strap or bonding strap/screw in place.
For individual circuits, neutral and grounds will hook to the neutral/ground bar, hots or line to the breakers.
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toyota_mdt_tech
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# Posted: 12 Apr 2012 14:11
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All wires need to be supported just outside of the panel, also make sure you insert those plastic inserts on any knockout plug to keep the wires from chaffing to the panel chassis. Then you should be ready to go!
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Rifraf
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# Posted: 12 Apr 2012 14:41
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Toyota, those are old images, each one has a plastic sheething at and just below the panel. I also filled each one with great stuff to prevent movement inside the conduit
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toyota_mdt_tech
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# Posted: 12 Apr 2012 16:10
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sounds good rifraf, you are ready to hit the main breaker and "power it up" then. 
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Bzzzzzt
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# Posted: 12 Apr 2012 16:37 - Edited by: Bzzzzzt
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Rifraf: If you're at all worried about the ground and the neutral being together (and frankly I wouldn't be) Drive a ground rod next to where the conduit enters the cabin and run a #2 bare copper wire from the ground rod to the panel. There SHOULD be a ground rod somewhere in the system anyhow. If you're relying on the pole ground it may not be adequate because a lot of times they just "butt wrap" the pole. That is to say, they just run a ground wire down around the bottom of the pole and call it good. Bond the neutral and the ground together wherever you put a ground rod and then keep them separate from then on.
That "green metal pin" as you call it is a bonding jumper and it is there to bond the neutral and the ground together at that panel. Only use it if this is where you're going to bond them together.
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Rob_O
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# Posted: 12 Apr 2012 19:01
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Quoting: Rifraf So can I just run the three wires into my sub panel and be done ? Meaning groundbus to groundbus, and hots from 125amp breaker to the sub panel lugs ?? and do I connect that little bus brigde thingy in the sub panel ?
If you have the wire to do it, I would recommend you use a main breaker at the cabin panel instead of the lugs
2 hots to the main breaker (or the lugs). Neutral to the neutral bus, connect the green pin to the neutral bus and drive a ground rod (or two) and connect to the panel with #4 copper
Simple enough?
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MtnDon
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# Posted: 12 Apr 2012 22:13 - Edited by: MtnDon
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As Rob_O says; hot to hot and neutral to neutral. Bond in place. Then a single bare ground wire to the first ground rod and continuing on to the second rod.
RR... not sure if you are comfortable with the terminology, hot, neutral ground? Do it as Rob_O says and if some time in the future a licensed electrician has a reason to be called he will instantly understand things. Running a neutral feed to a ground buss is not right, though the effect may be the same depending on the bond connection.
The feed from the power company to the main panel can be the hardest to understand it seems to me. Mostly because of that "bonding thing", IMO. Once past that it is fairly straightforward.
Just a thought. When you get to running the branch circuit wires leave enough wire to make it easy to have hot, neutral and ground wires to the beakers and busses in a manner to permit making nice 90 degree bends. Better than having wires criss cross each other all over. makes it easier to work on later for one thing. Just saying...
sort of like this...
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Rifraf
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# Posted: 13 Apr 2012 01:25 - Edited by: Rifraf
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Thanks guys
MtnDon, I think ive got enough wire in there for neat connections. Will know soon enough, but many of them are about 2 to 3 feet of lead left in the box.
for the rest of it now, i think ive got it
*Run things as expected from pole breaker to cabin lugs
*Run pole neutral to cabin neutral bus
*bury a large grounding rod, run cable from rod to cabin grounding bus.
*Turn green pin bonding jumper to the "ON" position, placing it into the nearby bus.
*Done
That about it ?
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Rob_O
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# Posted: 13 Apr 2012 20:08
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Quoting: Rifraf That about it ?
If you want your panel to be "by the book" use a main breaker and drive two ground rods at least 6 feet apart connected to the panel with #4 copper in an *uninterrupted* run from the furthest rod to the panel (or 2 separate wires). I've seen what happens when the transformer loses ground and the house ground becomes overloaded. You will only have to do this once so do it right the first time.
Quoting: MtnDon The feed from the power company to the main panel can be the hardest to understand it seems to me. Mostly because of that "bonding thing", IMO.
Yeah, it can be confusing. His "local guy" told him three wires so we can ignore the bond at the meter and think of it like any other residential panel. I'll be using one of those meter/panel combos at the transformer to feed the main house and a detached garage/workshop, county regs require a sticker on the panel so I'll have to do whatever the inspector is willing to approve.
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Rifraf
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# Posted: 20 Apr 2012 00:09
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Curious why you need two grounding rods for the sub panel at the cabin. As a fail safe in case one cable comes loose from one of the rods ?
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MtnDon
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# Posted: 25 Apr 2012 14:29
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Quoting: Rifraf Curious why you need two grounding rods for the sub panel at the cabin. As a fail safe in case one cable comes loose from one of the rods ?
One will do if there is less than 25 ohms resistance in the grounding circuit. Since it's hard to measure resistance without having two ground rods to measure between, 2 lets you take a good measurement. The reading is almost always never taken in the real world. 2 rods at least 6 feet apart.
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toyota_mdt_tech
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# Posted: 26 Apr 2012 16:58
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Quoting: Rifraf Curious why you need two grounding rods for the sub panel at the cabin. As a fail safe in case one cable comes loose from one of the rods ?
In my state, it is now code. They wont sign off till its done and no break in the copper wire feeding it. If its not signed off, power company will not hook it up.
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