Services & DistributionQuestion 52 of 521
As a general rule, how must a panelboard be protected against overcurrent?
a.By the branch-circuit breakers only
b.By an OCPD not exceeding the panelboard rating, on the supply side
c.It requires no separate overcurrent protection
d.By a GFCI device
Explanation
Per 408.36, each panelboard must be protected by an overcurrent device not exceeding its rating, located on the supply side (or within the panelboard as main). Branch breakers alone do not protect the busbar, and GFCI protects people, not the bus rating.
Law Reference: 2023 NEC §408.36Practice all 521 questions free — no signup required.
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