A.Rex Cauldwell responds: In my opinion, the only dependable way to detect live current — the way I would want to bet my life on — is with a multimeter connected to the wires. Check the voltage, conduit to ground, ground to hot, ground to neutral, and neutral to hot.
The wands, or "sniffers," I've used — the types you wave over the wires to tell you whether they're hot — have not been dependable. I have had many that gave false readings.
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