Mike Dolt Enterprises
Mike Dolt Enterprises
User: dynex22, Location: Mission Viejo, Ca.
Asked on: Thursday, April 7, 2011 at 8:19 pm EDT
Answered on: Tuesday, May 14, 2024 at 3:56 am EDT
Question: Need advice. Im working on a commercial building with 2-200 amp, 208/120, 3 phase load centers. I want to tap one for a 100 amp sub-panel. Can it also be a loadcenter or does it have to be a panelboard? (code?) Thanks!
Code Considerations
NEC (National Electrical Code) 408.3(4) states that a feeder shall not supply a panelboard having a lower ampacity than the feeder. NEC 408.15(A) states that a loadcenter is a panelboard used as a service equipment or as an interior distribution panel.Therefore, since the feeder from the 200-amp load center is rated at 200 amps, the sub-panel must also be rated at 200 amps.
Loadcenter vs. Panelboard
Loadcenter
A loadcenter is a panelboard that includes a main circuit breaker or fusible switch and overcurrent protection for the branch circuits.
Panelboard
A panelboard is a type of electrical panel that only contains overcurrent protection for the branch circuits and does not include a main circuit breaker or fusible switch.
Conclusion
Based on the code requirements and the specific circumstances described, the 100-amp sub-panel
must be a 200-amp loadcenter, as it must have an ampacity that is not less than the feeder supplying it. Flag for review