Need some home electrical help

[exranger06]

So I just bought a house, and I need/want to upgrade the electrical in the (attached) garage. I plan on adding a few large circuits, so I decided to install a 100 amp subpanel in the garage. My main question is, what size and type of wire and conduit should I use to feed the subpanel? The main panel is located in the finished basement, so the easiest way to get the wire to the garage is to use a knockout on the backside of the main panel, run a conduit on the outside of the house, and then go through the adjacent wall into the garage. The whole conduit will only be about 6 feet.

I need to know:
-Gauge and type of wire (jacketed? needs to be acceptable to use in outside conduit, etc)
-Type and size of conduit
-Any specific types of conduit fittings I should use (rated for outdoor use, etc)

Edit: I forgot to mention that yes, I'm getting a permit and it will be inspected.

 

[4wheeldog]

Originally Posted By: exranger06
So I just bought a house, and I need/want to upgrade the electrical in the (attached) garage. I plan on adding a few large circuits, so I decided to install a 100 amp subpanel in the garage. My main question is, what size and type of wire and conduit should I use to feed the subpanel? The main panel is located in the finished basement, so the easiest way to get the wire to the garage is to use a knockout on the backside of the main panel, run a conduit on the outside of the house, and then go through the adjacent wall into the garage. The whole conduit will only be about 6 feet.

I need to know:
-Gauge and type of wire (jacketed? needs to be acceptable to use in outside conduit, etc)
-Type and size of conduit
-Any specific types of conduit fittings I should use (rated for outdoor use, etc)

Edit: I forgot to mention that yes, I'm getting a permit and it will be inspected.


Go to Home Depot, and buy a small green and white pamplet titled "Wiring Simplified". It will give you most of the info you need. Or hire a contractor......Only you know how much skill you have, with this sort of project. Don't burn your house down....

 

[exranger06]

I'm confident I can do the work as soon as I have the materials in hand. I'm just having trouble selecting the materials. Not worried about burning the house down. The breaker is going to stay off until it passes inspection anyway.

 

[demarpaint]

Go to an electrical supply house, not a home improvement store and ask what you need for your project, and make sure you tell them you want it to meet code for your area.

 

[chefwong]

EX - I would use 2 THHN with 2" pipe....but your OP are VERY basic questions...

Buy a book and spend some time reading..

 

[Dufus2]

The electric supply house can advise you on what is required by state code for your 100 amp service panel. My dad did this years ago and it was like 2/0 cable, but I'm no expert on the subject.

 

[Donald]

I would think a knockout on the back of your main box will be hard to work.

Maybe hire an electrician to just install the new box. You can then add all the circuit breaker in it.

Remember branch box is isolated neutral. If you did not know that already, hire an electrician.

 

[user52165]

You want to do this yourself, which is commendable, but your questions indicate a basic lack of knowledge. As others have said, read up, do your research, get educated.

If you are unwilling, hire a contactor.

 

[JHZR2]

What is the distance of the run? Id start with 1 or 2 ga if Cu and 1/0 if Al and go from there, upsizing if the voltage drop is going to be a consideration due to length. Does it have to be 100A? Can you use a 75A breaker instead?

That's based upon a 60 degree insulation rating, which IIRC is the appropriate selection even if higher temperature insulation is utilized. If your conductors and terminations are all rated for 75 degrees then you may use the 75 degree column in 310.16. What is the wiring method? NM and SE cable would require the use of the 60 degree column in 310.16. 90 degrees is provided for derating purposes, and I doubt you have terminations rated for that.

http://www.houwire.com/products/technical/article310_16.html

Table 310.15(B)(6) is only for the entire load to a dwelling. A subpanel would require you to use table 310.16 to size the feeder conductors.


310.15(B)(6) 120/240-Volt, 3-Wire, Single-Phase Dwelling Services and Feeders. For individual dwelling units of one-family, two-family, and multifamily dwellings, conductors, as listed in Table 310.15(B)(6), shall be permitted as 120/240-volt, 3-wire, single-phase service-entrance conductors, service-lateral conductors, and feeder conductors that serve as the main power feeder to each dwelling unit and are installed in raceway or cable with or without an equipment grounding conductor. For application of this section, the main power feeder shall be the feeder between the main disconnect and the panelboard that supplies, either by branch circuits or by feeders, or both, all loads that are part or associated with the dwelling unit. The feeder conductors to a dwelling unit shall not be required to have an allowable ampacity rating greater than their service-entrance conductors. The grounded conductor shall be permitted to be smaller than the ungrounded conductors, provided the requirements of 215.2, 220.61, and 230.42 are met.

 

[exranger06]

Originally Posted By: Donald

Remember branch box is isolated neutral. If you did not know that already, hire an electrician.

Yup, knew that already.

 

[exranger06]

Originally Posted By: user52165
You want to do this yourself, which is commendable, but your questions indicate a basic lack of knowledge. As others have said, read up, do your research, get educated.

If you are unwilling, hire a contactor.

I've been reading, but I've been getting conflicting answers. I was just hoping someone could give me a straightforward answer instead of me doing lots of tedious research. If that's not possible, I'll do the research.

 

[HTSS_TR]

Originally Posted By: exranger06
So I just bought a house, and I need/want to upgrade the electrical in the (attached) garage. I plan on adding a few large circuits, so I decided to install a 100 amp subpanel in the garage.

I'm glad you post this question, I have similar question but didn't have the gut to ask.

I moved into my new house a year ago, I like to add a large circuit that can handle 5,000-6,000 Watts in my garage to charge the future Tesla Model 3 EV I plan to buy in 2017.

I'm subscribed to this thread and hopefully learn somethings. So far, I think I may need to hire an electrician to do it.

 

[JHZR2]

Originally Posted By: HTSS_TR
Originally Posted By: exranger06
So I just bought a house, and I need/want to upgrade the electrical in the (attached) garage. I plan on adding a few large circuits, so I decided to install a 100 amp subpanel in the garage.

I'm glad you post this question, I have similar question but didn't have the gut to ask.

I moved into my new house a year ago, I like to add a large circuit that can handle 5,000-6,000 Watts in my garage to charge the future Tesla Model 3 EV I plan to buy in 2017.

I'm subscribed to this thread and hopefully learn somethings. So far, I think I may need to hire an electrician to do it.


Does this imaginary 5-6000W load require 120/240V split phase, or true three-phase power to support a real level II charger on a 7-pin IEEE 1772 connector?

 

[chefwong]

Buy once or cry once on that the ev charging.
If you think it's sufficient, 6 wire ....for their charger. Just do the dryer plug with their convertor cable

If you want do it 1X or have the extra play money, you can always run 2 wire .

When I had my walls open, I just pulled 6 wire.