Testing & TroubleshootingQuestion 488 of 521
Which instrument lets you measure the current in a single energized conductor without disconnecting or breaking into the circuit?
a.A clamp-on ammeter
b.An in-line series ammeter on the DMM's 10 A jack
c.A megohmmeter
d.A non-contact voltage detector
Explanation
A clamp meter senses the magnetic field around a conductor, so you simply clamp its jaws around one wire while the circuit stays energized and intact. A series ammeter (b) requires opening the circuit and inserting the meter. A megohmmeter reads insulation resistance and a non-contact detector only indicates presence of voltage, not current.
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