30 CFR § 75.518
Electric equipment and circuits; overload and short circuit protection.
[STATUTORY PROVISION]
Automatic circuit-breaking devices or fuses of the correct type and capacity
shall be installed so as to protect all electric equipment and circuits
against short circuit and overloads. Three-phase motors on all electric
equipment shall be provided with overload protection that will deenergize all
three phases in the event that any phase is overloaded.