Main service panel codes

[Crispin Ramos]

After transferring loads out of the main service panel for the solar/battery back up system with my new company there were some things that I was under the impression could cause us to fail inspection. There was a ground wire coming into the msp wire nutted to another ground wire that was leaving the msp to the sun panel ground bus. Also all of the transferred circuits were wire nutted inside of the msp in front of the bussing where the breakers were. I was under the impression all grounds in main service panel must be bonded to the msp bus bar, and I was also under the impression you can’t wire nut inside the msp, my lead claimed these were both false.

 

[tom baker]

I can assre you wire nuts are allowed in the MSP. There is a limit based on the cross sectional area, highly unlikey to exceed that. I don't have a code book to post the section.
Also the EGC wire nutted together have to be the correct size per 250.122

 

[Crispin Ramos]

After transferring loads out of the main service panel for the solar/battery back up system with my new company there were some things that I was under the impression could cause us to fail inspection. There was a ground wire coming into the msp wire nutted to another ground wire that was leaving the msp to the sun panel ground bus. Also all of the transferred circuits were wire nutted inside of the msp in front of the bussing where the breakers were. I was under the impression all grounds in main service panel must be bonded to the msp bus bar, and I was also under the impression you can’t wire nut inside the msp, my lead claimed these were both false.