4 THW Aluminum Wire Sufficient Enough For Detached Garage Upgrade?
#1
12-03-15, 01:01 PM
Join Date: Dec 2015
Posts: 7
Upvotes: 0
Received 0 Upvotes
on
0 Posts
4 THW Aluminum Wire Sufficient Enough For Detached Garage Upgrade?
Im looking to run a little better wire out to my garage, currently the garage is fed via knob and tube in the air to the garage. Other then the lights dimming when my compressor turns on everything has seemed fine until I picked up a new table saw. Even though it does power the saw, I know I'm overloading the feed wire.
The house has a 100a panel with a few opened slots still, I was recently given a large roll of wire that has printed on it Cadillac 4 THW Aluminum and was wondering if this would be suitable to run from my main panel to a sub panel in the garage. If so I would want 3 wires to the sub panel, and add an additional ground rod outside the building as well? I don't have much need for 240v in the garage so I am more or less concerned with upgrading the 120v to the point where I know I am safe with standard power tools and lights and not worry about overloading.
But since I have this huge roll of wire, how many wires would I need to pull for a 120v240v sub panel? My garage is only about 25ft from the house and from the panel to the garage would probably be about 50ft, also is this wire suitable for direct burial?
Thanks in advance
The house has a 100a panel with a few opened slots still, I was recently given a large roll of wire that has printed on it Cadillac 4 THW Aluminum and was wondering if this would be suitable to run from my main panel to a sub panel in the garage. If so I would want 3 wires to the sub panel, and add an additional ground rod outside the building as well? I don't have much need for 240v in the garage so I am more or less concerned with upgrading the 120v to the point where I know I am safe with standard power tools and lights and not worry about overloading.
But since I have this huge roll of wire, how many wires would I need to pull for a 120v240v sub panel? My garage is only about 25ft from the house and from the panel to the garage would probably be about 50ft, also is this wire suitable for direct burial?
Thanks in advance
#2
12-03-15, 01:18 PM
Are you sure it isn't THHW? What gauge is it?
Best to runs four wires and install a 240 volt panel since you have the wire. Even if you did it 120 volt subpanels are special purpose not commonly available so you would end up using a 240 panel.
You could use four wire to run a multiwire circuit that would give you two 120 volt circuits no subpanel needed.
The wire would have to be in conduit. However with out knowing the gauge details can't be provided. Maybe it is #4 but what you wrote isn't enough to be sure. The name Cadillac as wire comes up blank on search. If it is THW it may be older wire.
Best to runs four wires and install a 240 volt panel since you have the wire. Even if you did it 120 volt subpanels are special purpose not commonly available so you would end up using a 240 panel.
You could use four wire to run a multiwire circuit that would give you two 120 volt circuits no subpanel needed.
The wire would have to be in conduit. However with out knowing the gauge details can't be provided. Maybe it is #4 but what you wrote isn't enough to be sure. The name Cadillac as wire comes up blank on search. If it is THW it may be older wire.
Last edited by ray2047; 12-03-15 at 01:34 PM.
#3
12-03-15, 01:27 PM
The wire needs to be in a continuous conduit between panels. Where buried, the conduit needs to be at 18" depth. The conduit should be at least 1-1/4" trade size. The wire can supply up to 70A, although 60A is a more common panel size.
If you are going to the trouble of installing a panel, why not pull 4 conductors and have a standard 240/120 panel?
If you are going to the trouble of installing a panel, why not pull 4 conductors and have a standard 240/120 panel?
#4
12-03-15, 01:39 PM
Join Date: Dec 2015
Posts: 7
Upvotes: 0
Received 0 Upvotes
on
0 Posts
Well at first when my friend said he had a role of wire I could have I thought Yay I can upgrade my 120v in the garage but now that I am seeing the amount of wire there really is yes I would be running a 120/240 panel.
The wire appears to be 6g about I will grab a pic or two of it, and also says 600v on it as well.
Give me a few minutes I will get a picture.
The wire appears to be 6g about I will grab a pic or two of it, and also says 600v on it as well.
Give me a few minutes I will get a picture.
#7
12-03-15, 02:05 PM
Yeah that's 4 gauge aluminum THW. It'll be tricky to roll out without being on a spool, so take your time with that. Kinks or twists will make the conduit pull impossible. When you make the pull, the neutral must be taped white at both ends and the ground must be taped green.
#10
12-03-15, 02:58 PM
what size breaker should I use in the main panel?
For your subpanel I'd suggest a 100 amp 12 space main breaker panel kit. The main breaker will serve as your disconnect. They are about the cheapest way to go and even include some branch circuit breakers. Usually they do not include a ground bar so you will need to buy one. You also need a ½"x8' ground rod at the garage. Just remember this when connecting the ground rod if you use the aluminum:
250.64 (A) Aluminum or Copper-Clad Aluminum Conductors.
Bare aluminum or copper-clad aluminum grounding conductors
shall not be used where in direct contact with masonry
or the earth or where subject to corrosive conditions.
Where used outside, aluminum or copper-clad aluminum
grounding conductors shall not be terminated within 450 mm
(18 in.) of the earth
Bare aluminum or copper-clad aluminum grounding conductors
shall not be used where in direct contact with masonry
or the earth or where subject to corrosive conditions.
Where used outside, aluminum or copper-clad aluminum
grounding conductors shall not be terminated within 450 mm
(18 in.) of the earth
#11
12-03-15, 05:28 PM
Join Date: Dec 2015
Posts: 7
Upvotes: 0
Received 0 Upvotes
on
0 Posts
Thanks for all the info guys. Yes as you can see in the pictures I also got a bunch of other wire as well so I will use copper for my ground rod.
