main breaker for Panel

[Leo Li]

As below showing there is no main brealer for panel DPEM3(circled with red), I wolud like to know if this is isolation from NEC and actually I can't find related item for this. Thanks!

 

[tom baker]

Where have you looked in the NEC?

 

[Leo Li]

Where have you looked in the NEC?

I didn't find but it will lose disconnecting means for panel DPEM3.

 

[petersonra]

I didn't find but it will lose disconnecting means for panel DPEM3.

I don't see a problem with this arrangement. The 400 amp feeder breaker protects the bus in this panel board and serves as a disconnecting means if needed. The code never requires a main breaker to my knowledge.

 

[augie47]

Are both panels in the same building. If so I agree with petersonra

 

[Leo Li]

Are both panels in the same building. If so I agree with petersonra

They are in the same building but not in the same room. Other panel's main breaker is available but only this panel main breaker is missing. I didn't know the reason and don't know if this isolation code. Thanks !

 

[Leo Li]

I don't see a problem with this arrangement. The 400 amp feeder breaker protects the bus in this panel board and serves as a disconnecting means if needed. The code never requires a main breaker to my knowledge.

Thanks!

 

[infinity]

Here's the relevant code section. The OCPD can be at the origin of the feeder and is not required to be in the panelboard.

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. This overcurrent protective device shall be located within or at any point on the supply side of the panelboard.

 

[Leo Li]

Here's the relevant code section. The OCPD can be at the origin of the feeder and is not required to be in the panelboard.

This is clear for me now. But I prefer to put main breaker inside this panel to easy disconnection and miantenance this panel. Thanks!

 

[infinity]

This is clear for me now. But I prefer to put main breaker inside this panel to easy disconnection and miantenance this panel. Thanks!

That's a common reason for MCB's in panels but it's a design issue not a code issue. I've seen value engineering where they remove the 400 amp main in the panel to save the cost of a 400 amp CB.

 

[tom baker]

This is clear for me now. But I prefer to put main breaker inside this panel to easy disconnection and miantenance this panel. Thanks!

And I agree with that