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Pro tip: stop using that old multimeter for fridge compressors
I was at a job in a high rise downtown, working on a fancy fridge that kept tripping its thermal overload. My trusty Fluke 87V showed the compressor windings were fine, so I spent an hour checking everything else. The owner, an old timer who was watching, finally asked to see my meter. He pulled out his own and got a reading of 0.8 ohms on the start winding, while mine showed a clean 3.2. My meter's leads were so worn the internal resistance was throwing off low ohm readings. I've had that meter for over a decade and never thought to check the leads. How many of you actually test your meter leads for resistance before diagnosing a compressor? I feel like an idiot.
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leelewis11d ago
Man, that's a tough lesson to learn the hard way. It's so easy to trust your main meter when it's been reliable for years. Those little things like lead resistance just sneak up on you. I've been burned by that before on low voltage control circuits, not compressors, but same idea. Makes you want to just short the leads together first thing every morning out of habit now.
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owens.ben10d ago
Read an article once about guys in industrial maintenance doing exactly that. They called it a "zero check" before every shift. Just touch the leads together, see if you get anything other than zero. Seems like such a simple habit that saves so much headache. Makes total sense after getting fooled by a meter you thought was perfect. That false sense of security is the real problem.
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lindamartin10d ago
Ever check your leads first?
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