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Tried a Fluke multimeter vs a cheap no-name one for a tricky 737 troubleshooting job
Had a weird intermittent fault on a 737's pitot heat system last Wednesday. Grabbed my usual cheap meter from the truck, got all sorts of wonky readings that made no sense. Swapped to a Fluke 87V my buddy loaned me and traced the issue to a bad relay in 10 minutes. The cheap meter was picking up noise from the AC bus. How often do we chase ghosts just because of bad gear?
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anthonymurray26d ago
A cheap meter picking up AC bus noise? That's a serious safety hazard waiting to happen.
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pat_schmidt6026d ago
Start by checking if that cheap meter has a safety rated input like a CAT II or III. Most of those no-name ones skip the overvoltage protection and just use a tiny resistor, so when that AC bus noise spikes from a big motor starting or something, the meter blows up in your hand. I've seen it happen with a guy testing a breaker panel, the meter just popped and the leads melted together. That's not just a false reading risk, that's a hot arc flash waiting to happen.
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holly_henderson8626d ago
Oh man, that's exactly what I saw happen at a buddy's garage last year. He bought one of those $15 meters off Amazon to test a dryer outlet, and the thing literally smoked and sparked when he touched the probes to the terminals. The LCD screen went black and the leads got so hot they started melting the insulation. He was lucky he jumped back when he heard the sizzle, otherwise that arc flash could've taken his hand off. I've been using a cheap Fluke 101 for years now, it's not fancy but at least it's actually tested for CAT ratings. Seriously people, that $20 savings isn't worth the hospital bill or worse.
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