Which type of receptacle needs ground fault circuit interrupter protection during temporary wiring installations?

Ground fault circuit interrupter (GFCI) protection is essential for specific types of receptacles used in temporary wiring installations, particularly in environments where the risk of electrical shock is higher, such as construction sites or outdoor activities. The 30 ampere receptacle is designed for heavier-duty applications and can power equipment that draws significant current. Due to this higher capacity and the potential for increased hazards associated with such usage, the National Electrical Code (NEC) mandates GFCI protection for these receptacles to enhance safety.

The need for GFCI protection with 30 ampere receptacles stems from their common use for tools and large appliances that could be operated in wet or damp locations, where the risk of ground faults is significantly increased. GFCI devices monitor the electrical current flowing in a circuit and cut off power if an imbalance is detected, providing critical protection against electric shock.

In contrast, receptacles rated at 15-20 ampere may not require GFCI protection in all temporary installations, while higher rated receptacles (25 ampere and 40 ampere) may also have distinct applications that depend on specific regulations or projects, but do not warrant a blanket requirement for GFCI protection in the same way as the 30