Yet another alkaleak story - Fluke voltage tester damaged

Kitchen Panda

Aug 28, 2011
Today's wiring project was to replace a household light dimmer with the correct model (I learned the hard way that "halogen" on the label doesn't mean "transformer operated MR16 halogens"), and to install a combo USB/AC outlet in the kitchen to simplify the ugly snarl of wall warts we were using for charging devices.

I grabbed my heavy electrical toolkit and was disappointed that my Fluke voltage tester pen had blown the end cap off! Revealing the AAA batteries within emanating corrosive goop. (Luckily I have another volt tester and a meter, so the Fluke was only going to be a backup to verify that I had turned off the right breaker.)

This was an early model tester. I've had it for more than 20 years...the model that replaced it was discontinued in 2009. Can't find it on line, but it doesn't beep and has a metal pocket clip. Can still barely read "Fluke" on the barrel, but all the rest of the text is worn off. It has a tightly-sealing screw down plastic cap, and the barrel is essentially airtight so any H2 gas given off by rotting alkalines has nowhere to go.

It's my own fault, of course. I recalled that I'd changed the batteries a couple of times in this unit in all the time I had it..but not since I retired. I was ashamed to read the label on the batteries that said "Best before 2017". I can't fault the maker for that.

Maybe I can save the voltage tester...I got a flicker out of the LED when I tried a new set of batteries in it, so maybe it just needs to finish drying out after I cleaned it. I'll have to glue the end cap back on. Luckily I found the contact spring, which will also need some cleaning. Don't think it will be reliable again, but maybe OK for my occasional light homeowner use.

Just as well, this style is no longer considered safe as it doesn't make any sound and has no self-test features.

EDIT: Two days later, the Fluke has completely dried out after cleaning, and appears to be working well with a couple of lithium AAAs. My plan is to glue the cap together first, then screw it on...sad experience has taught me not to get Crazy Glue into threads I want to undo ever again.
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