An old master electrician told me my meter was lying - he was right

I was working on a three-phase motor in an old warehouse last Tuesday and kept getting weird voltage readings on my Fluke. The guy I was with, who has been doing this since the 70s, walked over and said my meter was lying. I thought he was kidding at first but he had me check the connections by touching the leads together first. Turns out I had a bad test lead that was giving me intermittent readings about 15 volts off. That hit different because I always assumed my gear was perfect out of the box. He told me he tests his leads every morning before starting a job. Has anyone else had a tool you trusted just give you bad data out of nowhere?

3 comments

3 Comments

terry_carter1516d ago

Funny how we all treat our meters like they're infallible. But think about it this way - your test leads get thrown in a tool bag, stepped on, pinched in doors, and abused daily. The meter itself might be fine but those leads take a beating. His morning routine sounds like overkill until the day it saves you from chasing a phantom problem for three hours. I started taping a cheap set of spare leads to the inside of my lid after a similar experience with a fluke 87 that was reading 10 volts low on one leg. Trust the tool but question the connection, that's what I took away from it. Nobody ever talks about how much time we waste blaming the equipment when it's usually the little things.

the_tara16d ago

And what gets me is nobody ever checks the input jacks on the meter itself, those little receptacles get packed with dust and grime from sitting in a dirty truck and can cause intermittent readings just as bad as a bad lead. I had a meter once that would pass all the lead checks but still gave weird readings until I finally took a can of air to the jacks and pulled out a clump of dried mud. We focus so much on the visible parts of the connection chain but the one inside the meter is just as likely to be the culprit.

riley_schmidt5d ago

Dont buy that for a second. If your meter jacks are that packed with crap then you're probably not taking care of your tools in general. A good meter seals those jacks tight enough that dust and mud aint getting in unless youre dunking the thing in a puddle. Also weird readings from dirty jacks usually show up as open circuits or wild jumps not small consistent errors that fool you for hours. People blame the meter too much when really they just dont know how to test their leads properly. Spend the money on a decent meter and stop making excuses for cheap gear.