Question 1
In a 3-wire, single-phase 120/240V system, what is the most likely result of a 'loose' or 'open' neutral conductor in the main service?
Question 2
An electrician is troubleshooting a circuit where the load is not receiving power. A voltmeter shows 120V at the source breaker and 120V at the outlet's 'hot' terminal relative to ground, but 0V between the 'hot' and 'neutral' terminals at the outlet. What is the most likely fault?
Question 3
In a 3-wire, 120/240V single-phase system, what is the most likely symptom of an 'open neutral' conductor in the main service?
Question 4
When troubleshooting a 3-phase motor that refuses to start and hums, an electrician measures the current on all three legs. Phase A = 12A, Phase B = 12A, and Phase C = 0A. What is the most likely diagnostic conclusion?
Question 5
An electrician is troubleshooting a circuit where the lights are flickering intermittently. A measurement shows 120V at the source but only 95V at the fixture while under load. What is the most likely cause?
Question 6
An electrician is troubleshooting a lighting circuit where all lamps are out, but the breaker is not tripped. What should be the FIRST step?
Question 7
A GFCI breaker trips whenever it rains. The circuit feeds an outdoor receptacle. What is the most likely cause?
Question 8
A customer reports a breaker that trips instantly when reset. A resistance test from the load terminal to ground reads 0.1 Ohms. What is the most likely fault?
Question 9
If you measure 120V from hot to ground but 0V from hot to neutral at a receptacle, what is the most likely problem?
Question 10
When checking for a 'short circuit', what reading would you expect on an ohmmeter between the hot and neutral wires?