Testing & TroubleshootingQuestion 518 of 521
By mistake you clamp your ammeter around BOTH the hot and neutral conductors of a single-phase 120 V branch circuit that is drawing 8 A. What will the clamp meter most likely read?
a.8 A
b.16 A
c.Approximately 0 A
d.120 A
Explanation
The hot and neutral carry equal and opposite currents, so their magnetic fields cancel when both are inside the jaw, giving a reading near 0 A. To read true load current you must clamp only one conductor. A non-zero reading around both would actually indicate leakage/ground-fault current.
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