Feeder Size Vs Panel Size

[mesarush1]

Is it legal to bring a feeder sized smaller than the rating of the panel it supplies? Example: 100amp mcb-#4 wire feeding 200 amp mlo panel.

 

[celtic]

As long as the OCPD is sized properly, sure.

 

[infinity]

I agree. Many of the commercial panels we install are fed with 100 amp feeders but the bus is typically rated for 225 amps.

 

[Dennis Alwon]

Is it legal to bring a feeder sized smaller than the rating of the panel it supplies? Example: 100amp mcb-#4 wire feeding 200 amp mlo panel.

I agree with the others but a #4 with a 100 amp OCP is questionable. If it's a residence then you must abide by art. 310.15(B)(6) and Table 310.15(B)(6).

No romex in this situation and it must be the feeder between the main disco & lighting and appliance branch panelboards.