[marly]

I want to install a sub panel in my attached garage with a 60 amp breaker.
The wall between house and the main panel is approximately 50 feet. I could put the subpanel in the wall that separates the garage from the house, but I would rather not poke any wholes through the firewall, plus getting all the receptacle electric lines would require me to drill holes through the top plates between, walls and it seems really labor intensive, plus the panel ends up in a not so convenient location. I think I could get away with 6 AWG wire for this run.

The other idea I have is, is run the wire in the basement along the floor joists (in conduit obviously), behind the garage, exit the house, bury the conduit in the ground for about five feet and go back into the garage. The location for putting the panel there is really convenient, the biggest one being the walls on that side of the garage aren’t finished so fishing wires all over the place would be quiet easy. I don’t need to put any receptacles on the firewall side of the house because there are enough receptacles that came with the house there. The only problem I can think of with this is the distance for this run is about 100 feet and it would require 3 AWG wire, which is a lot more expensive that 6 AWG wire, plus it’s twice the distance.

Does anyone have any better ideas? I really would rather not cut into the firewall on the house and poke a lot of holes in there for the sub panel, probably by the time I’m finished I’m probably tearing out a whole finished wall.

marly

 

[vsheetz]

100 ft run will not require #3 - #6 is ok for 60 amps at that distance.

 

[secutanudu]

According to this voltage drop calculator, vhseetz is right, you will have less than 5% voltage drop over 100 feet for 120v circuits.
http://www.csgnetwork.com/voltagedropcalc.html

You need minimum 3/4" if you use schedule 40 pvc, according to this raceway fill calculator. I'd do 1".
http://www.electrician2.com/calculators/rf_calculator.html

You don't have to run in conduit in your basement ceiling. You can use 6/3 romex (w/ ground) then convert to 4 individual strands of THWN wire in a junction box before exiting with conduit.

Conduit must be buried 18" deep.

 

[marly]

I was over at my Dad’s house and he has a 500’ spool of #4 THNN/THWN wire with a temperature rating at 90C.

What’s max amperage I can get out of a #4? Since it’s a 500’ spool of black, can I just put electrical tape on the ends to change the color or would I need to pull the correct color of wire through?

It would be nice if I could use the 500' spool of #4, the price is right.

marly

 

[frenchelectrican]

I was over at my Dad’s house and he has a 500’ spool of #4 THNN/THWN wire with a temperature rating at 90C.

What’s max amperage I can get out of a #4? Since it’s a 500’ spool of black, can I just put electrical tape on the ends to change the color or would I need to pull the correct color of wire through?

It would be nice if I could use the 500' spool of #4, the price is right.

marly

If they are copper they can go much as 100 amp only in dry location but wet location 70 or 80 amp no question asked { I have to double check NEC chart to make sure due I know European verison can run 105 amp max }

Second question about remarking the THHN/THWN it is not a issue to remarked due they are larger than 16mm²{#6awg} but check with your inspector first about that some may not like to use all black conductors however as long they are remarked on larger conductor it is NOT a issue I have done it very often I am sure other electricians will echo on this one as well.

For 100 foot run a single 500' spool of 25mm² {#4} will cover it very nice if you get a good price deal.

Merci,
Marc