DEVICE FOR DETERMINING IMPROPER REVERSAL AND/OR SHORT OF GROUND AND NEUTRAL LINES AND AMOUNT OF IMPEDANCE IN GROUND LINE OF A THREE-WIRE A.C. OUTLET

摘要

A three wire ground type AC outlet tester for testing (1) the correctness of socket wiring of three-wire receptacles, including neutral-ground reversal or shorting errors, (2) the magnitude of electrical impedance in the ground circuit, and (3) the existence of undesirable excess voltages, the tester including signal injecting means for injecting a test pulse into the ground-neutral circuit, a threshold detector responsive to a sensed magnitude value for responding to the amount of impedance in the ground circuit, and indicating means energized for indicating the presence of an amount of impedance in the ground neutral line which exceeds pre-set threshold impedance levels. The tester includes means for positively indicating an improper reversal or shorting of ground and neutral connections at the terminals of a test outlet and further includes means for providing a distinct indication of either an open ground or open neutral wiring error.