# Thread: MLO Sub-panel with inverter and loads wire sizing

1. Junior Member
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## MLO Sub-panel with inverter and loads wire sizing

Hey Guys,

I have a situation and wondering if my thinking is correct and looking for the applicable codes.

I have a 60A subpanel which has a 20A breaker for an inverter and a 20A breaker for a light.

This would be legal according to the sum rule in 705.12(d)(2)(3)(c). But how do we size the wires coming out of the subpanel? Because the currents are going in opposite directions the max current on that wire be 20A and should be sized for that shouldn't it?

Thanks

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Originally Posted by ryangittens
Hey Guys,

I have a situation and wondering if my thinking is correct and looking for the applicable codes.

I have a 60A subpanel which has a 20A breaker for an inverter and a 20A breaker for a light.

This would be legal according to the sum rule in 705.12(d)(2)(3)(c). But how do we size the wires coming out of the subpanel? Because the currents are going in opposite directions the max current on that wire be 20A and should be sized for that shouldn't it?

Thanks
Yes. The most current those conductors will carry is 20A.

3. Junior Member
Join Date
Feb 2017
Location
usa
Posts
29
Originally Posted by ryangittens
Hey Guys,

I have a situation and wondering if my thinking is correct and looking for the applicable codes.

I have a 60A subpanel which has a 20A breaker for an inverter and a 20A breaker for a light.

This would be legal according to the sum rule in 705.12(d)(2)(3)(c). But how do we size the wires coming out of the subpanel? Because the currents are going in opposite directions the max current on that wire be 20A and should be sized for that shouldn't it?

Thanks
Just realized that this is a stupid question. The conductors are sized based on and protected by the OCPD on the other end.

4. Senior Member
Join Date
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Location
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Originally Posted by ryangittens
Just realized that this is a stupid question. The conductors are sized based on and protected by the OCPD on the other end.
That, too.

5. Junior Member
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usa
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Originally Posted by ggunn
That, too.
Haha thanks

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