How does one test a CD spindle motor?
Kerry moke
Thanks so much :)
Bman
If it's a portable discman of some sort, 3V or if a home CD player,
maybe 9V or so.
If it spins, you're in luck!
Byron
On Fri, 31 Jan 2003 22:53:57 +1300, Kerry moke <mo...@moke.com> wrote:
Bob Parker
If you applied 9V to one of those, it might spin so fast that the
windings would fly off the armature. That's my experience anyway.
I was fairly successful at checking them by connecting them to an
analog multimeter on the lowest ohms range. This should make it rotate
pretty fast.
Then you hold the spindle and very slowly rotate it through a
single revolution, watching the meter needle. If you find any spots
where the resistance drops really low and/or it stops trying to turn,
that's a sign that it's got a problem.
I hope this is of some use.
Cheers,
Bob
bm...@niagara.com (Bman) wrote:
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Sam Goldwasser
> Simply apply an appropriate voltage directly to its two wires.
>
> If it's a portable discman of some sort, 3V or if a home CD player,
> maybe 9V or so.
>
> If it spins, you're in luck!
This assumes it's a based permanent magnet DC motor. Higher X CD drives
may use multiphase brushless motors which are more difficult to test.
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Dave D
"Sam Goldwasser" <s...@saul.cis.upenn.edu> wrote in message
news:6wk7gle...@saul.cis.upenn.edu...
> bm...@niagara.com (Bman) writes:
>
> > Simply apply an appropriate voltage directly to its two wires.
> >
> > If it's a portable discman of some sort, 3V or if a home CD player,
> > maybe 9V or so.
> >
> > If it spins, you're in luck!
>
> This assumes it's a based permanent magnet DC motor. Higher X CD drives
> may use multiphase brushless motors which are more difficult to test.
>
Also, just because a dc motor 'spins up' is absolutely no indication of its
serviceability for CD use. It could be weak or have excessive wear in the
bearings.
Dave
Bram Stolk
hooked up across a small series resistor in the motor supply lead. Apply
some torque with your finger tip. It will surely tell you whether it's noisy
and irregular.
"Kerry moke" <mo...@moke.com> schreef in bericht
news:3e3a...@clear.net.nz...
Angulos
motors run at approx. 2.6 VDC....by reversing the connection you can see the
motor running backwards...BTW the + and - are well written on the PCB where
the two motors are mounted.
Alphie
Sam Goldwasser
This assumes it's a simple permanent magnet DC motor. High X CD drives
may use multiphase/brushless motors which can't easily be tested.
Bob Parker
>My preferred method for any brush type of motor is to have the oscilloscope
>hooked up across a small series resistor in the motor supply lead. Apply
>some torque with your finger tip. It will surely tell you whether it's noisy
>and irregular.
Ah yes,
I've used that technique too, and it gives a very good indication
of the condition of the commutator and brushes.
Perhaps some readers of this newsgroup aren't fully aware of how
little disturbance to the rotational speed of the motor it takes, to
empty/overfill the digital buffer memory which handles the data coming
from the pickup. This is why the condition of the motor, including its
bearings, is so critical. Simply putting volts onto it to see if it
rotates isn't enough.
And yes Sam, thanks for drawing attention to the fact that they
don't all use little DC motors. :)
Cheers,
Bob
Kerry Moke
Very funny a faulty one out of a CD does that,
leeppp
Unsolder one of the motor wires b4 applying an external voltage source
for safety. These tiny motors have really cheap oilite bearings and
#very tight# clearances between rotor and stator.Usually 3v or less
will spin up a good cd motor with good bearings and a #spot# of very
thin oil on dry bearing. Spin it up manually 1st to see if shaft is
too tight. there should be some runout on these Perm.Mag. motors. ...
I `ve ruined a couple by applying too much power(E xI). I doubt
whether my Simpson 260 would spin one up slowly but, maybe...dunno.It
would be nice if they used regular ball bearings. LEE
Sheldon
when voltage is applied, but when in use and under load may not work as
designed. A slow motor may look okay to the eye, but not spin the CD fast
enough for the rest of the circuitry to work right.
Sheldon
she...@sopris.net
"Kerry moke" <mo...@moke.com> wrote in message news:3e3a...@clear.net.nz...