Re: 12VDC motor problems
- From: Uriah <uriahsky@xxxxxxxxxxx>
- Date: Wed, 31 Dec 2008 14:03:18 -0800 (PST)
On Dec 31, 3:54 am, JonSutton <j...@xxxxxxxxxxxx> wrote:
Uriah wrote:
I have a 12VDC wiper motor that is being used in one of those animal
cranes as a drive for a platter. It stopped working and I have taken
it apart and am stuck. What it does is that it works for about a
minute then starts slowing down and then stops. If I turn it off and
wait a minute it will do it again. There doesn't appear to be any
shorts on the wires wrapped on the inside. I am a little confused on
how this thing works. It has three brushes, two are opposite at 12:00
and 6:00 and one wired to the frame is at about 8:00. There are also
two blue Varistors??? wired between the ground and each brush, at the
input plug, not in the motor. They have CNR written on them and then
100820k under that. What are they used for? And why the three brushes
in that kind of configuration? And... how are you supposed to wire
these up? being that there are three brushes? And why does it stop
running. The manufacture in AU said that it was losing magnetic
power??, is that possible? They want over $300.00 for a direct
replacement. I found surplus motors that are close for $20.00. Any
help on this one? Thanks so much
Russ
I would suggest that the 3rd brush is wired to another external terminal
- It's for running the motor at a higher speed - It's probably a 2 speed
automotive windscreen (windshield) wiper motor after all.
I've not seen one with the 'varistors' as described, but they're most
likely to be small capacitors to provide brush noise suppression.
Does the motor slow down when run from an alternative source? The
problem may lie in the supply of the unit...
What's an 'animal crane' btw?
Jon
That makes sense. The third brush has to do with speed. It is a wiper
motor. Those blue things could be caps. They show cap values and
test open. Maybe I don't have a strong enough PS, so I will try from
another larger PS. The crane is actually called Chocolate Factory by
ICE. Very similar to regular animal cranes but you pick up candy
bars. It drops them on a platter and then the platter pushes them
forward and if your lucky some will fall in to your arms. That
platter is the problem. You know you might be right about the PS not
being strong enough. When I found the crane broken it lost the 12
volts and the platter wasn't turning. A bridge rectifier went out so
I replaced that and I thought the motor caused the problem because of
the results I got with it on the bench. So I had ordered a surplus
motor that almost fits and the machine is back up working. I was just
puzzled about this motor and why it stops. I will test again on a
bigger PS today. I bet that that is the problem not enough
amps.....
Thank you
Russ
.
- References:
- 12VDC motor problems
- From: Uriah
- Re: 12VDC motor problems
- From: JonSutton
- 12VDC motor problems
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