Master Electrician Exam 2025 – 400 Free Practice Questions to Pass the Exam

The maximum number of 15-amp receptacles allowed on a single 15-amp circuit is typically up to 10 receptacles. This guideline is based on the National Electrical Code (NEC) recommendations which suggest that for general-purpose receptacle circuits, the total load of all devices should not exceed 80% of the circuit's capacity.

A 15-amp circuit has a maximum capacity of 1,440 watts (15 amps multiplied by 120 volts). However, it is recommended that the circuit be loaded to a maximum of 12 amps (which equates to about 1,440 watts at 120 volts) to maintain safety and ensure there is some capacity available for surges in current demand and to prevent nuisance tripping of breakers.

Given that typical receptacles are designed to draw a certain amount of current (usually calculated at 1.5 amps per receptacle for general use), the total number of receptacles should not exceed 10 for practical and safety reasons while accommodating potential usage without overloading the circuit.

This practice helps ensure that even if multiple devices are plugged in, there remains a buffer to prevent overheating and ensure safe operation of the electrical system.