On Jul 22, 8:44*am, (Wolfgang Allinger) wrote:
*On 19 Jul 11 at group /sci/electronics/repair in article
*(Wild_Bill) *wrote:

Much depends upon what type of motor is in the ceiling fan. There are
more than one type of AC motors without brushes.

Klem/Lenny hasn't revealed what type of AC motor he's referring to..
nor anything specific regarding the "generic" controller that wasn't
supplied with the fan.

Here in PY there are lots of ceiling fans from Wahson/China.

230V/50Hz

They use a separate autotransformer in an aluminium housing (15x9x4 cm) *
as controller.

It is in series with the motor and has 7 taps and a turning switch with *
weird numbered positions from 0 = off and 1=max ... 7=slowest speed!
The motor so gets between 230V and down to some 80V.

My 5 Wahsons did not buzzing, even in slowest speed.

However I have 2 fans (also made in china) with no external controller *
but a small hanging line which switches between 3 different speeds by *
taping different positions in the motor winding. They both are buzzing *
in speeds below max. I think thats in the remaining active sectors of *
the winding.

None of these motors have brushes.

Saludos Wolfgang
--
Meine 7 Sinne:
Unsinn, Schwachsinn, Blödsinn, Wahnsinn, Stumpfsinn, Irrsinn, Lötzinn..
Wolfgang Allinger * Paraguay * * * * * * reply Adresse gesetzt !
ca. 15h00..21h00 MEZ *SKYPE:wolfgang.allinger

I would like to try the trick with the capacitor in series with the
slowest tap on the speed control however I am a bit unclear as to how
to "size" the capacitor. By "size" I mean that it seems like if the
motor draws one amp for example, (and I will confirm that first), I
will need a capacitor that can handle more than that amount of current
flowing through it. I remember dealing with this sort of thing in
electronics school, but admittedly that was a very long time ago and
I've forgotten how to work this out.

For instance, I have a 4uf 250V AC capacitor that I would like to try.
This part is designed for motor starting. This is a fairly large
capacitor. The control box measures approximately 8" x 6" X 3". Most
of that space is taken up by the switch and transformer. There would
not be room inside for anything this large. Or do I need to use
anything this large? Thanks, Lenny