Re: RV garage
Reply #53 –
Back to the wire size and subpanel issue. 3% voltage drop is normal for conductors downstream of panels. Panelboard wire size are based on CB size to protect the wire. Probally never see max load or voltage drop only after an extended power outage. Circuit breakers are sized as the MAXIMUM OVERCURRENT PROTECTION DEVICE (MOCP) or MFS maximum fuse size. To try to protect the end user this is based on inrush current. Wire size is typically based on the MCA rating to a appliance. This is known as diversity. Is it safe to have 42 20 amp breakers in a 200 amp panel yes. Ignorant AHJ
or installing contractor may tell you otherwise.