It would be worthwhile to include more details in your posts, as you've been
criticised for previously.. so days later someone may realize what it is
your talking about.
This drive got a name, p/n, or voltage marked on it? Someone may have a
schematic/wiring diagram or other useful info for a similar drive if you
would give details.
It appears that a voltage is present for the field (but it may not be the
The motor also needs an armature voltage A1-A2.
The armature voltage isn't getting to the armature.
Failed drive circuitry.
Switch device open.
Half-assed previous repair/anything.
The armature voltage is the one that's controlled by the circuit.. any of
the components associated with the motor speed could have failed.
I've read more than a couple of times that speed pots had failed in a
certain table drive.. Enco maybe. There may be some info and/or a schematic
in the dropbox archives.
It may be that the drive motor runs all the time because it failed before
and some motor monkey found a way to make it run.
You've seen considerable wear present, but you'll likely spend hours trying
to make the old drive work, possibly poorly or only briefly, then hold out
for another used drive for cheap.
Possibly you were thinking you'd get an old machine that you'd be able to
use for years without ever spending a dime on it.
The machine probably didn't cost much but if you aren't willing to spend
some money on it, you probably just dragged it back to scrap it.
Plan B.. put a handwheel on the feedscrew.. which is a good plan, that may
even dissuade the operator from walking away from an operating machine.
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