A socket tester ;is a portable electrical instrument used to test for correct operation and wiring standards on power outlet sockets. It is typically a hand-held instrument that either plugs directly into the socket with pins mounted on the tester or come equipped with a short lead and plug. Depending on the sophistication of the socket tester, a range of status indications may be returned including disconnected phases, reversed phases, and, in the case of a top-end instrument, earth loop impedance.
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