New York City Electrician Practice Test 2026 - Free Electrician License Practice Questions and Study Guide

Think of a 120/240 V circuit as having two hot conductors that are 240 V apart, with each hot being 120 V relative to ground (the neutral is bonded to ground at the service panel). A breaker labeled 120/240 V is designed to protect circuits that can have up to 120 V on a single conductor with respect to ground, while the two hots can be 240 V apart. So the voltage to ground is 120 V. The other options don’t fit because the typical residential layout does not provide 240 V to ground on a single conductor, and saying “any voltage up to 240” ignores the specific ground reference, while “none of these” is incorrect.