How is the amperage calculated for a 120V circuit with multiple light fixtures operating continuously for 8 hours a day?

• A. 12.50A
• B. 12.75A
• C. 13.50A
• D. 13.75A

Answer: (D)

To calculate the amperage for a 120V circuit with multiple light fixtures, the fundamental principle involves using the formula for electrical power and the relationship between voltage, current, and power. The power formula is defined as:

Power (P) = Voltage (V) × Current (I)

In this scenario, if you know the total wattage of all the light fixtures combined, you can rearrange this formula to solve for current:

Current (I) = Power (P) / Voltage (V)

If the total wattage of the fixtures is known, you could substitute that value into the formula along with the voltage of 120V. For example, if the total wattage of the connected fixtures is 1,650 watts, the calculation would be as follows:

I = 1,650 watts / 120 volts = 13.75A

This demonstrates how the calculation results in 13.75 amperes, which indicates that the circuit can safely carry that amount of current without overheating or causing other electrical issues over the 8 hours of continuous operation.

Thus, understanding your total wattage from the fixtures is crucial in determining the correct amperage for ensuring the circuit operates effectively within its limits. It also emphasizes the importance of