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new subpanel or quad breaker?

PoorOwner

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I wanted to have these in the garage as the end result:

240V 40A (for welder, NEMA 6-50P receptacle)
120V 20A lift or power tool (but not the same time)
120V 20A (120V Air conditioner)

1) Should I have electrician put in a subpanel, the run the new receptacles off it.

2) or, use 20 40-40 20 breaker outside in the main then conduit into inside.


considerations:

I would like to take as little slots from the main where this is coming from, but I think both options would occupy just 2 blanks, with option 2 being a quad breaker.

With the subpanel, the cost will be higher (probably, much higher for professional install) and you are not allowed to put items or shelves in front to block access to the subpanel. Taking up that space is kind of a big deal for the amount of space I have in the garage.

One thing I did not think about is the wire fill rate in EMT, especially for option 2 , for 2 x 8 awg + ground 4 x 8 awg + ground?
 
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PoorOwner

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is this garage in the same structure as the main panel?

Yes the main and meter is on the garage exterior wall. It will be a short run of wires thru the stucco to the interior wall on the same side.
 

ard

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Are you planning on doing option 2 yourself? Or both of these electrician jobs?

My point would be if you can do 2 you can do 1.

Where in CA? Roughly.

I'd put in a 60A breaker in the main panel, run a little subpanel into the garage. Not a hard job. Is the garage open stud bays? Or insulated and sheetrocked??
 

cort

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Having the breakers in the direct area of use is the way to go for a workshop. Not having to run outside to shut off a breaker or to reset a tripped breaker is worth the expense. Sub-panel is the way to go. Also, allow for some expansion capacity in your new sub-panel. Do you park cars in the garage? Is an electric car with charging station in the future? A 50A or 60A service can be consumed pretty quickly. Consider 100A (usually 3 ga copper wire) if your condition will allow.
 
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mike93lx

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i would recommend a subpanel....

I agree.

If not, have you confirmed that you can add a quad breaker to your panel? Make sure that the specific breaker you select is listed for the panel and that your panel allows tandems. If it does allow them, it is common to only have certain spaces setup for them, which may require moving around a couple breakers. Not a big deal, but something to be aware of.
 
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wyliesdiesels

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Having the breakers in the direct area of use is the way to go for a workshop. Not having to run outside to shut off a breaker or to reset a tripped breaker is worth the expense. Sub-panel is the way to go. Also, allow for some expansion capacity in your new sub-panel. Do you park cars in the garage? Is an electric car with charging station in the future? A 50A or 60A service can be consumed pretty quickly. Consider 100A (usually 4 ga copper wire) if your condition will allow.


#4 cu is too small for 100a. Need #3 cu...
 

alfredeneuman

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Fullerton, CA
240V 40A (for welder, NEMA 6-50P receptacle)
120V 20A lift or power tool (but not the same time)
120V 20A (120V Air conditioner)
>>>>>>>>>>>>>>>>>>>>>>>
One thing I did not think about is the wire fill rate in EMT, especially for option 2 , for 2 x 8 awg + ground 4 x 8 awg + ground?

You only need #12 for the 20A circuits.
Only the current carrying conductors are subject to derating, so the grounds aren't counted.
You could run those conductors all in 1 conduit, and not be worried about derating :)
 
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PoorOwner

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What size of breaker and sub panel do i need? Both 60A and what cu wire?

The main already has a 125 amp going to the garage for house circuits. So I don't want to overkill this one. I know I did not seem like I asked for a lot but the garage interior already has a couple of 15a circuit for garage doors and for the small stuff and the air compressor is already in.

The walls are finished.

I don't know the panel specs and need to dig further because the stickers got rotted away. But hopefully the panel support duplex breakers.

No electric car in the near future but we would try to use another 2 slot on the main panel when that happens.
 
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mm08822

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What size of breaker and sub panel do i need? Both 60A and what cu wire?

The main already has a 125 amp going to the garage for house circuits. So I don't want to overkill this one. I know I did not seem like I asked for a lot but the garage interior already has a couple of 15a circuit for garage doors and for the small stuff and the air compressor is already in.

The walls are finished.

I don't know the panel specs and need to dig further because the stickers got rotted away. But hopefully the panel support duplex breakers.

No electric car in the near future but we would try to use another 2 slot on the main panel when that happens.


What does this mean - the garage already has a subpanel?? Please explain.
 

mm08822

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It has a 125A breaker in the main breaker panel feeding a challenger subpanel, filled 100% full of house circuits.

Well this is your lucky day.
Replace that Challenger panel with a bigger panel. Challenger panels are junk (as in safety related issues) and having a 2nd sub panel in the garage would be a little odd.

So how many circuits are in the Challenger panel now?
What are the loads in that panel?
Depending on your answers above, you may be able to re-use the existing 125a feed.
Also what are the details of the 125a feed - # of conductors, conductor gauge, type of cable, etc.?

Pics help.
 

wyliesdiesels

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Modesto, CA
Yeah replace the challenger garbage. The money u would spend on another subpanel can instead go to a new larger panel.

No sense in having 2 subpanels.

Hopefully the feeder is 4-wire which it should be since its in the same structure as the main.
 
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