Chapter 12 of 123% of exam
Electrical
Electrical (3 of 115 items) covers the coordination and safety of power systems on commercial jobs. This chapter reviews ground-fault protection.
GFCI protection and jobsite power
A ground-fault circuit interrupter (GFCI) monitors the current leaving and returning on a circuit; if it detects an imbalance, such as current flowing through a person to ground, it trips quickly to prevent electrocution. OSHA requires GFCI protection (or an assured equipment grounding conductor program) for temporary construction power. Permanent wiring is installed per the National Electrical Code (NEC) and inspected before energizing.