Question 9.23: For safety reasons the National Electrical Code restricts th...

Basic Engineering Circuit Analysis [EXP-40319]

For safety reasons the National Electrical Code restricts the circuit-breaker rating in a 120-V household lighting branch circuit to no more than 20 A. Furthermore, the code also requires a 25% safety margin for continuous-lighting loads. Under these conditions, let us determine the number of 100-W lighting fixtures that can be placed in one branch circuit.

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