Sub panel for ev charger

[Airmoses]

I have a sub panel in my garage already but its coming off a double pole 60 amp breaker off the main panel. Not sure why the electrician did that as the wire looks like it is 2awg which i rates for 125 amp. Am i reading the wire correctly? So i should be able to replace the 60 amp break with a 125 no?

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[zipzag]

no, 100 amp on the 80% rule

 

[240vPlug]

Could be load calcs would not allow for more than 60 amps. Also depends on the size of your load center and how many other loads you have.

If you have a 200 amp service your continuous load should not be more than 160amps at any given time. If you exceed the capacity of your panel you could run into serious safety issues.

 

[Airmoses]

I have 200 amp service and the sub panel is only 4 feet away from the main panel

 

[jjswan33]

I have 200 amp service and the sub panel is only 4 feet away from the main panel

In which case your panel must be full, so what @240vPlug said likely applies. Look up what that means, nothing to do with the sub panel or wiring to it.

 

[Revelation]

2awg is rated for 125A but as another poster stated it is 100A going by the 80% rule. Either way, unless there is something else you are not telling us, you can use a larger breaker for your sub panel.

I would like to know more details to give you better advice. Does your subpanel have a main breaker in it?

Load calcs shouldn't limit the breaker size since 2awg was ran. If they ran 4awg then sure that would make more sense. Again, based on what you have said, I would upgrade the breaker. With more details my opinion may or may not change.

 

[Airmoses]

I have $1k as the deductible (which is the maximum I'm allowed to have on my loan docs)

2awg is rated for 125A but as another poster stated it is 100A going by the 80% rule. Either way, unless there is something else you are not telling us, you can use a larger breaker for your sub panel.

I would like to know more details to give you better advice. Does your subpanel have a main breaker in it?

Load calcs shouldn't limit the breaker size since 2awg was ran. If they ran 4awg then sure that would make more sense. Again, based on what you have said, I would upgrade the breaker. With more details my opinion may or may not change.

This is my sub panel in the garage, the 2 30 amp breakers in there are always off unless Im using my table saw or the heater (which i never use). So I think best thing is for me to change the 60 amp breaker on the main panel supplying this box to 100 amp and use that 60 amp breaker in this box for the charger.

 

[Airmoses]

In which case your panel must be full, so what @240vPlug said likely applies. Look up what that means, nothing to do with the sub panel or wiring to it.

I had the subpanel put in my garage, it’s only for the garage and outside the house. My main panel which is on the other side of the wall in the basement is just for inside the house.

 

[Zoidz]

What's the rating of the subpanel? It looks like it is probably a 125A subpanel, but make sure. If the subpanel is rated at 60A, you don't want to feed it with 100A breaker.

 

[Dark-Fx]

MTW was a strange choice here. 105C rated copper but you can't use above 75C in residential. You could breaker the sub panel for 100A but your neutral and ground wires need to be properly sized too, I can't see either of those in this panel. Panel also has to be rated for the load you're putting on it.

 

[Revelation]

This is my sub panel in the garage, the 2 30 amp breakers in there are always off unless Im using my table saw or the heater (which i never use). So I think best thing is for me to change the 60 amp breaker on the main panel supplying this box to 100 amp and use that 60 amp breaker in this box for the charger.

So far I do not see any reason why that would not work. If you do go that route, ensure that you use 6awg THHN/THWN wiring in conduit if you plan to use the 60A breaker. If you use 6/2 or 6/3 Romex you will need to use a 50A breaker.

 

[Airmoses]

MTW was a strange choice here. 105C rated copper but you can't use above 75C in residential. You could breaker the sub panel for 100A but your neutral and ground wires need to be properly sized too, I can't see either of those in this panel. Panel also has to be rated for the load you're putting on it.

The cable going to the subpanel is BX so wouldnt it be properly sized?

 

[Airmoses]

What's the rating of the subpanel? It looks like it is probably a 125A subpanel, but make sure. If the subpanel is rated at 60A, you don't want to feed it with 100A breaker.

 

[Airmoses]

So far I do not see any reason why that would not work. If you do go that route, ensure that you use 6awg THHN/THWN wiring in conduit if you plan to use the 60A breaker. If you use 6/2 or 6/3 Romex you will need to use a 50A breaker.

wouldnt use 4 awg? User manual says 12 to 4 awg. I figured for the largest breaker I would use 4 awg.

 

[Revelation]

wouldnt use 4 awg? User manual says 12 to 4 awg. I figured for the largest breaker I would use 4 awg.

I don't believe 4awg will fit in the terminals in the Wall Connector. There's no point in running 4awg with the added cost over 6awg. Further you have 4awg running to the panel to feed all of your loads.

6awg THHN or THWN is rated for 60A and 48A continuous on the 80% rule.

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