New garage. Electrical advice

[Tugmaster]

I’m in the process of building a 20x25 detached steel garage. I worked it out with my local electrician for me to rough in all the electrical and he’ll wire everything up and make sure it’s correct and up to code.
My house has 200 amp service. I plan on installing a small sub panel. I’ll need 220 for a 3-1/2hp air compressor and 220 for a 110/220 MiG welder. I’ll also need to wire for overhead lighting and a half dozen electrical outlets along with a outlet for my garage door opener. Since it’s a steel building I’ll have to run all my wiring thru conduit. I have a few questions.

What size breakers for the 220 outlets? I plan on two separate circuits.

How many outlets per breaker? The first on will be GFCI.

Obviously I’ll be using led for overhead lighting. I know they don’t draw a lot so can I do 8 on one circuit?

I’m thinking of using 3/4” pvc conduit. Any pros or cons compared to steel conduit?

Thanks,
Todd

 

[Hot Rod Grampa]

Your welder and air compressor will determine what amperage your breakers, wire and style of receptacle will be. Quad boxes around the workbench on 2 separate circuits allows more flexibility in case more than one tool is used at the same time. I do not believe there is a max limit on receptacles per circuit. If you are not proficient with a tubing bender, you have a choice. Learn a new skill or go pvc. Have fun.

 

[Jkcolo22]

No more than 4 outlets on a 20 amp circuit and you’ll be happy. Popping a breaker when you have a fan and a table saw plugged in is frustrating.


Sent from my iPhone using Tapatalk

 

[wyliesdiesels]

I’m in the process of building a 20x25 detached steel garage. I worked it out with my local electrician for me to rough in all the electrical and he’ll wire everything up and make sure it’s correct and up to code.
My house has 200 amp service. I plan on installing a small sub panel. I’ll need 220 for a 3-1/2hp air compressor and 220 for a 110/220 MiG welder. I’ll also need to wire for overhead lighting and a half dozen electrical outlets along with a outlet for my garage door opener. Since it’s a steel building I’ll have to run all my wiring thru conduit. I have a few questions.

What size breakers for the 220 outlets? I plan on two separate circuits.

How many outlets per breaker? The first on will be GFCI.

Obviously I’ll be using led for overhead lighting. I know they don’t draw a lot so can I do 8 on one circuit?

I’m thinking of using 3/4” pvc conduit. Any pros or cons compared to steel conduit?

Thanks,
Todd

the size of the breaker will depend on several factors. Is the compressor motor rated @ 3.5HP on the nameplate?

What model welder do you have? You would most likely use a 50a circuit for the welder

 

[ambenz]

Some reference material....
https://www.finehomebuilding.com/forum/conduit-metal-vs-pvc

A good Google search for electrical garage basics.....
https://www.google.com/search?sourc...i8i13i30j0i8i13i10i30j33i22i29i30.AWG-hJrMLGA

 

[dcg9381]

No more than 4 outlets on a 20 amp circuit and you’ll be happy.

I disagree with this. In terms of code, there is no limit (that I know about) that says X outlets per 20A breaker. It's more about "what" you're going to put on the circuit.

If you're running a table saw, you don't want it on the same circuit as your refrigerator, for instance.

My take is that you need to plan out where your "high draw" things are and design your circuits around that. Use dedicated (or semi-dedicated) circuits where appropriate.

If you don't know and have to do a "long run" of outlets ever X feet, I like to alternate circuits down the same run - meaning two circuits feeding alternate outlets down a wall.

There are instances where I don't want the slop of a power strip, but I do have a lot of relatively-low power devices, such as phone charger, speaker charger, LED TV, USB cameras, etc. Literally I have 9 outlets sitting in my "AV area" - and probably 6 other outlets on the same circuit. It's a "low amp use" circuit and I want the "location" of the outlets to be right for my use. If I was connecting a table saw, I'd do it differently.

 

[cybrdyke]

Obviously I’ll be using led for overhead lighting. I know they don’t draw a lot so can I do 8 on one circuit?

8 of them will be easy, unless they're HUUUUge. You can probably save yourself a few bucks by using 14AWG wire, too.
CD