What is the maximum permissible load on a 15-amp residential circuit?

• A. 1,000 watts
• B. 1,500 watts
• C. 1,800 watts
• D. 2,400 watts

Answer: (C)

The maximum permissible load on a 15-amp residential circuit is 1,800 watts. This is determined using the formula for electrical power, which is calculated as the product of voltage and current. In residential settings, the standard voltage is typically 120 volts.

To find the maximum load, you multiply the current capacity of the circuit (15 amps) by the voltage (120 volts). Therefore, 15 amps multiplied by 120 volts equals 1,800 watts.

It's important to also consider the National Electrical Code (NEC), which suggests that circuits should not be loaded beyond 80% of their maximum capacity for continuous loads. For a 15-amp circuit, the 80% rule would further limit the safe operating load to 1,440 watts. However, the question focuses on the maximum permissible load without considering continuous usage, making 1,800 watts the correct value under those conditions.