Eddie6789
Dec 1, 2006, 01:24 PM
I’ve had the meter and 3 wire service cable removed from my shop. I’ve purchased 90 feet of 100 amp direct burial cable to run from the lower section of my home meter to my shop. Not being an electrician, I’m still trying to install this changeover. The direct burial cable has 4 wires. 2 larger black wires, 1 larger black with white striping, and 1 smaller green wire. My assumption is that the 2 larger black wires connect to the connections going into the breaker panel. Now my problem arises. Where do the other 2 wires connect? Now to my 2nd problem. I know the 2 black wires connect to the lower side of my home meter. There are only 3 wires going to the top side of my home meter. Where do the black wire with stripe connect and where does the green wire connect? Both my home and my shop have ground rods driven into the ground. I hope I haven’t confused anyone as much as I am confused. Thanks for your help. Eddie6789
Fr_Chuck
Dec 1, 2006, 06:48 PM
1. This could and should not be done without a building permit and inspected by the building inspector
2. If you don't know what you are doing, don't do it, you will end up burning your house or shop or both down
3. If the other service was for a business, and you were deducting the electric as a business expense, when it is hooked to your home, it would no longer be deductable,
tkrussell
Dec 2, 2006, 06:39 AM
The four wire direct burial cable you have should be called URD, or Underground Residential Distribution cable. The two black wires, note one may have a red tracer to be able to tell the difference between both, are the hot wires, the large wire with a white tracer is the neutral, these three should be all #2 or larger for 100 amp.
The green wire is the equipment ground, and is the most important wire.
At the house panel the two hots will connect to a 2 pole 100 amp breaker to feed the shop. Now, if the house panel has the Main Breaker in that panel, both the Neutral and the green will connect to the Main Neutral bar in the Main Panel.
If the Main Panel does not have a Main Breaker in it, then the Neutral connects to the Main Neutral, and the green wire will connect to a separate equipment ground bar that should be in the Main Panel.
At the shop, connect the hots to the shop panel Main Breaker or lugs.
Here is where it will get tricky, so pay attention.
The Neutral wire of the URD cable will connect to the Main Neutral bar.
If the shop panel had a Main Breaker in it, look closely at the Main Neutral bar for a jumper or a green screw that connects the neutral bar to the metal can of the panel, find this and REMOVE the jumper and/or screw. THIS MUST BE DONE to isolate the Neutral from the metal panel box AND the equipment grounding. Purchase and install an equipment ground bar, mount directly to the metal panel box with machine screws, no sheetmetal screws allowed.
The green wire of the URD cable will now connect to this new equipment bar.
Disconnect any wire connected to the Neutral bar that goes out to any ground rod or water line. Move any bare or green wires FROM the main Neutral bar and connect to the new equipment bar.
If the shop panel did not have a Main Breaker in it, then this separation of Neutral and equipment grounds should already been done for you.
The newly connected shop panel is now a subpanel and the Neutrals and grounds MUST BE separated.
If your home is a single family dwelling, then you may be allowed to do your own electrical work, providing you obtain an electrical permit from your local Code Enforcement or Building office.
And have all your work inspected, including having the direct buried cable inspected BEFORE the cable is covered.
There are specific details on how to bury cable also, depending on your local codes, soil conditions, type of cable, and if installed in conduit.
What Fr Chuck is trying to tell you if you don't have the installation permitted and inspected, and if your electrical work causes any loss of life or property, your insurance carrier will not cover any losses, and you may be criminally responsible for any injury or loss of life.
Consult with your accountant on the tax issue.
I am not confused at all. Any confusion on your part can be disastrous.