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I'm just about to run a generator service line through a buried conduit. My question relates to the proper size of the ground wire.
I'm going to pull a 220 service thru 1.250" PVC conduit. I'll use 1 black 8 ga and 1 red 8 ga for the hot feed. 1 white 8 ga will be neutral. What would be the recommended ga for the green ground wire? Does it also have to be 8 ga? My books say that the ground wire MUST be 8 ga min, but they are talking about the wire that leads from the service buss to the pipe or ground rod. Will this also apply to the ground wire that I run inside the conduit with the service feed?

Bski, to the best of my knowledge, if you use a ground rod at each end (generator and shed service box) you do not need to run a 4th (green) line through the conduit. Use 8 ga to hook ground up to the ground rod at each end.

Neutral and ground end up at the same place, a ground rod. For the most safety, do as Theo says, drive a ground rod at both ends and use the 8ga.

BTW did you ever rig up a remote choke/starter system?

I'm too tired to look up your old thread.

The ground rods are already a planned "given". 8 ga wire, too. Thanks.
Are we talking "national code" by eliminating the continuous ground in the conduit?

More of a cipher.

Ground?...GROUND?...We dont need no stinkin ground(This comment from a guy that puts quaters behing the screw in fuses to assure a GOOD connection)
Bski,Dont go cheap on the wiring,you dont want voltage drop due to too small a wire.Ground&nuetral are just as important as the hot wires.

After you have the wires hooked into the electrical source, remember to test by placing the wires againest your tongue. No reason to put in all this work and not know if your connections are flawed.

Not an electrician but did stay in a Holiday Inn last night!

Now thats a voltmeter!

...more cipherin', no doubt

With ground rods, your ground wire is approximately 8,000 miles in diameter. Not sure of the AWG, I defer to Theo.

That's up somewhere in the "aught" sizes.

I talked with B-I-L, the electrician. Absolutely yes, there should be a continuous ground. Normally, with EMT conduit, it's metallic construction would mechanically provide the ground continuity. With PVC conduit, a 4th wire must be run. He recommended 10 ga for the ground wire.

Brettski,

I just read this thread. Glad you contacted your B-I-L. He is absolutely right.

I'm not an electrician, but for nearly 40 years my job has required me to deal with safe and unsafe power distribution on land, at sea, and in the air. More than once I've somehow cheated death because of mis-understandings of proper safety.

In an installation like this, don't skimp on the ground wire and the mechanical ground connections. Try to check it at least annually. Measuring the voltage between neutral and ground, while the line is under load, is a good way to evaluate it. There shouldn't be more than a few volts difference -- if there is, find the problem. Make sure to use Ground Fault Interrupters. Corrosion, frost damage, and many other conditions can easily create life-threatening situations.

Sorry to sound so grim. I, for one, really enjoy and value your posts. I'd sure hate to see them suddenly stop.

Stay safe,
Ken

I'm not a trained electrition, but I've totally wired two homes. I'm not ever going to say you can have too much ground wire, but the neutral wire connects to the ground bar and the ground bar connects to the ground rod and the ground rod connects to the kneebone..... point being the ground and neutral connect at the same junction. Seems to me if you have ANY voltage differance between ground and neutral, there is a bad connection on the lower voltage wire. IIRC the "gounded plugs we now use did not exhist until the late 60' or early 70's and were only added to the code to correct polarity problems. Some of us older guys can remember having to flip a plug when you got a tingle touching a fridge and metal counter trim......

I'm sure I'll get corrected soundly for this post...

Not soundly!

The ground and neutral should only connect at the breaker box. The neutral and hot wires have current running through them when they are suppling power to a device. In a proper system, the ground wire should not have any current running through it. As a consequence, there will be a voltage drop across the neutral wire which will not occur on the ground wire. Thus, there will be a voltage difference between neutral and ground at the load end of the wires. On short runs of heavy gauge wire it should be barely noticeable. On long runs, like a few hundred feet of extension cord, it can be several volts.

Not by me.

Brettski, is your BIL a Windy City 'Lectrician? My sister's FIL is an Electrician from Chicago; there are several standard Ohio wiring practices that he has found strange (and vice versa).

A GFCI will fault when there is voltage between ground and neutral. That's what they do. I totally agree on using the metal conduit as the ground wire. Though, I'm not an electrician, I have tested a few outlets with a coathanger, and stayed at a Holiday Inn Express.

...remember when Burger was just a single Burger Jr

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(sigh...)
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He does most of his work in the collar counties; places that still remember what PVC conduit looks like.

Originally Posted By: burgermeisterThough, I'm not an electrician, I have tested a few outlets with a coathanger, and stayed at a Holiday Inn Express.
...remember when Burger was just a single Burger Jr

Looks like hes gonna get "grounded"

The neutral (white) connects to the neutral bus bar in the breaker box. The ground (bare copper) connects to the ground bar that is a separate bar that mounts to the back of the box. The ground bar is not connected to the neutral bar at all. It is connected via a 10 gauge green wire separately out to the meter box then right to the ground rod. That is the only place the neutral and ground meet, at the meter box and ground bar.

IIRC that varies with local codes. Breaker boxes generally come with a removable strap connecting ground to neutral that can be removed where needed.

I have an older house(34 yrs) in Houston and the white(neutral) and bare copper(ground) are on the same bus at the breaker box. The newer code may be different.

Every Breaker box you buy tells you a ground bar is required (sold seperately) for proper installation.

This may well be true on where they connect in your box. BUT, the metal circuit box itself is a complete circuit between the two bars since they will both be fastened directly into the box without being insulated or isolated from the box. Two seperate bars is not uncommon in setups with a lot of circuits---still doesn't make any differance which bar is used.

To answer Brettski's original question, you do need to run at least a #12 ground wire back to the ground bus in the panel. If the panel is your main panel, the ground and neutral will be tied together. If it is a sub panel, they will be sepatate. At least that's the code here is Ga.

Now looking back at your question, are you pulling this power FROM your generator, or TO your generator?