Yo bro! Your web page is phenomenal! Here's a story you might be interested in. Subject: a GE heavy duty dryer. Symptoms: would blow fuses every couple of weeks or so. This dryer has two fuses; it always blew the same one - the one that handled the heating coils. So you'd put in a load and the motor would run, but nothing would get dry. I'd replace the fuse and then all would be fine - for 2 weeks. I figured it couldn't be a short in the dryer or the fuse would blow right away, right?

I checked that the outlet wasn't obstructed with lint. I checked that the drum rotated freely when turned by hand. I measured the current draw with my clamp-on ammeter and all was normal, on both fuses. What strange intermittent problem was causing this fuse to blow? OK, give up? I finally looked closely at the fuse socket and discovered that the threads were a uniform light brown in color. I got out my voltmeter and found that I got zero volts from the center terminal to the threaded shell of the socket - unless I pressed down hard with the probe.

Somehow this socket had built up a layer of corrosion or varnish (or something) over the years. Inserting a new fuse tightly was enough to establish contact to make the dryer run, but with enough resistance to cause the fuse to heat up. Since the fuse is unable to distinguish between overheating because too much current is flowing through it and overheating because, well because it's just too hot, it would blow. I carefully sanded the varnish off the socket until it was a nice shiny silver color, put in a new fuse, and it's been fine ever since (over 1 year now). I found this case interesting because what looked for all the world like an intermittent, really wasn't.

Next project - replace all those old fuses with a breaker panel. --

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