Hi, I'm installing a 125 amp sub panel in my garage for power tools. Will
be installing a 70 amp breaker in the load center to feed the sub. Will be
installing 240v circuits along with 120v. What wire size do I need to go
with from load center to sub? Distance is bout 30'.
You need three #4 copper wires and a #8 green or bare copper wire for the
ground. You could possibly
use #6 if your load calculation comes to 65A or less, but you must use 75C rated
cable in this case,
such as SER. Number 6 copper NM cable can't be used unless you limit the breaker
to 60A. If running
individual THHN wires, you could also use #4 for the two hots and #6 for the
neutral as long as some
of your load has 240V only appliances.
This is Turtle.
Most everything i do is Commercial and i tend to over do things as residentiual
wiring goes but here is my view on it.
You can get you some 3 wire # 4 / with Naked ground and all in casing. You need
to get it in TW, THW or THWN types strands and your
rating will be above any 70 amp breaker you may want to use. You will have a
black and red to use for your two hots and a white used
for your common and a naked ground wire used for your ground wires to the
appliances or the sub panal. You need to try to keep the
naked gound seperated from the white common wire for you don't want the naked
ground being used as the common in the circuits.
Now if you want to use some THHN type wire in conduit. you can use #6 for the
two hots and some #8 for common and some #8 for the
naked ground or ground wire only and if coated must be green.
Yea, i know I over killed it but i can't run the line on wire but alway fair on
the larger side.
Outgoing mail is certified Virus Free.
Checked by AVG anti-virus system (http://www.grisoft.com ).
HomeOwnersHub.com is a website for homeowners and building and maintenance pros. It is not affiliated with any of the manufacturers or service providers discussed here.
All logos and trade names are the property of their respective owners.