Final answer:
An RV 120v supply panel requires a main breaker, individual circuit breakers, possibly GFCIs, outlets for appliances, and adherence to the National Electrical Code (NEC) for safe operation.
Step-by-step explanation:
An RV 120v supply panel must have various components for safe and efficient operation. It should include a main breaker to protect the overall electrical system, individual circuit breakers for each circuit to prevent overloads, and potentially Ground Fault Circuit Interrupters (GFCIs) to protect against electrical shock. Furthermore, it should be equipped with outlets for plugging in various appliances and may have an integrated surge protector to safeguard against voltage spikes. Wiring should be done in compliance with the National Electrical Code (NEC) to ensure safety.