Caught myself using a meter wrong for a decade

I was out on a service call in a new build in Huntersville last spring and the house lights kept flickering. I checked voltage at the panel and it read fine, 120 on each leg. Then a guy I was working with just looked at my meter leads and asked if I ever zeroed them out. I had been using my Fluke 117 for about 10 years and never once hit that relative button. Turns out my leads had a tiny resistance that was messing up my continuity and low voltage readings the whole time. I always blamed wire problems or bad breakers when stuff acted weird. Has anyone else missed something that simple for years?

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rileyl983mo ago

The relative button zeroes out lead resistance for low ohms but it won't fix a voltage reading unless your leads are actually bad. If your Fluke 117 was showing 120 on each leg with no load, that's probably fine because voltage measurements are high impedance and don't care about a few milliohms of lead resistance. The flickering issue might have been something else like a loose neutral or a bad connection somewhere downstream. I had a similar thing where I was chasing a phantom voltage drop and it ended up being a backstabbed outlet that was barely hanging on.

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morgan_butler3mo ago

Buddy of mine @rileyl98 ran into almost the exact same thing. He spent hours chasing a flickering light in his basement. Thought it was the main panel. Swapped breakers. Still flickered. Turned out one of the wires on a cheap push-in connector was barely touching. Pulled it out, used a screw terminal instead, problem gone. Those backstabbed connections are garbage. I don't trust them for anything.

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