gene heskett wrote:
>From an oldtimer who is also a CET:
Look any fuses in the original supply over, either with an ohmeter,
replacing anything over 2 ohms, or with a very strong magnifying glass,
looking for stress fractures of the fusible element.
Old fuses have expanded a wee bit and sagged, until they break a hairline
fracture but it looks like a good fuse at a cursory glance. Any fuse that
serves in a circuit passing more than about 25% of its rating will
eventually fail while looking good, but its fractured and broken on a
real close examination.
An argument could be made (if the fuse is in the line power part of the
circuit) to place an ne2 neon lamp, in series with a 56k 2 watt fireproof
resistor across any fuse holder found to be hiding such a failure, so if
it breaks again 10 years down the log, the ne2 will tell you its failed
by lighting up. But it won't be passing enough current to be a threat to
a human.
Hi Gene,
Thanks. As you see I had created a stupid short. The 24v supply is a 1.2
amp open frame, old school analog. I was seeing 5 volts on that rail so
it was really putting out. The rest of the drop was on some 30 feet of
#22. I think it is #22. Good supply just going into current limiting and
not dying. It was hot! For all I know, it was putting out several amps,
and I'm guessing it was with 5 volts showing.
I have a big redo planed for that mill. I'm running 2.6 on it. I'll move
to 2.9 and get that touch off actually working. Such a pain to set up
with a test tool and feeler gauge. And those flanges, best we could do
was put a pointy tool in and set it over the middle. Amazing how well
you can see down to ~<.001.
Best, Dan.
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