60 amp feeder to 150 amp main breaker panel

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yired29

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Would the following installation be a code violation?

120/208 3 phase 60 amp feeder with #6 THHN feeding a 42 circuit 150 amp main breaker panel load calcs are good at 60 amp OCPD and # 6. All terminations 75 deg.
 
yired29 said:
Thats the way I see it as well. The 60 amp OCPD provides the protection. The only problem I could see is if the 150 amp OCPD in the panel was not listed for #6 wire.
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Lug listing would be the only hold back. Other than the lug wire rating you could feed a 400amp panel with #12 on a 20amp DP breaker.
 
408.36 permits the installation the way you have explained it in your post.



408.36. Overcurrent Protection.
In addition to the requirement of 408.30, a panelboard shall be protected by an overcurrent protective device having a rating not greater than that of the panelboard.
 
I agree it's allowed . An other way to do it . Take the main 150 out of the panel. Fill the space with a listed method.
Then install a 60 with a breaker clamp on the bus bar. Bring your service wires to it. Mark it MAIN.
Then you have a 150 breaker available for an emergency call some day.;)
 
Buck Parrish said:
I agree it's allowed . An other way to do it . Take the main 150 out of the panel. Fill the space with a listed method.
Then install a 60 with a breaker clamp on the bus bar. Bring your service wires to it. Mark it MAIN.
Then you have a 150 breaker available for an emergency call some day.;)
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They are not 'service wires', they are feeder conductors. I do not believe you would call it a "MAIN" either.
 
Pierre C Belarge said:
They are not 'service wires', they are feeder conductors. I do not believe you would call it a "MAIN" either.
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Pierre if you leave the 150 main breaker in the panel it is probably marked main. I don't see where marking the breaker that turns off the entire panel a main is an issue-- please explain.
 
Buck Parrish said:
I agree it's allowed . An other way to do it . Take the main 150 out of the panel. Fill the space with a listed method.
Then install a 60 with a breaker clamp on the bus bar. Bring your service wires to it. Mark it MAIN.
Then you have a 150 breaker available for an emergency call some day.;)
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That's another way to do it, but I don't know that its any better. If you have a fault after the second 60A, but before a branch, you don't know which 60A will trip.

Dennis Alwon said:
Pierre if you leave the 150 main breaker in the panel it is probably marked main. I don't see where marking the breaker that turns off the entire panel a main is an issue-- please explain.
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Most panels that I've seen come with a sticker labeled "MAIN" and a bunch labeled "SERVICE DISCONNECT." I've never been absolutely sure where they are to go...
 
I don't see any problem calling it a "main." What else would you call it?

If he was labeling it "service disconnect" then that would be a different story.
 
Cow said:
I don't see any problem calling it a "main." What else would you call it?

If he was labeling it "service disconnect" then that would be a different story.
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I agree. It is the main breaker for that panel board. It's not the service disconnect though.
 
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