Testing & TroubleshootingQuestion 503 of 521
A homeowner reports a 'weird' outlet. Which instrument most quickly indicates common miswires (open ground, open neutral, reversed polarity) at a 120 V receptacle?
a.A megohmmeter
b.A clamp-on ammeter
c.A plug-in receptacle (three-light) tester
d.A phase-rotation meter
Explanation
A plug-in three-light receptacle tester lights a coded pattern that flags open ground, open neutral, and reversed polarity instantly. A megohmmeter tests insulation, a clamp meter reads current, and a phase-rotation meter is for three-phase sequence, none of which quickly maps outlet miswires.
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