Subject: Re: Can one repair (large) blowers?
To: Gunther Schadow <port-vax@netbsd.org>
From: Chuck McManis <cmcmanis@mcmanis.com>
List: port-vax
Date: 05/31/2001 07:56:18
At 02:19 PM 5/31/01 +0930, Geoff Roberts wrote:
>Just pulled one down, has six transistors and an IC. Much like the
>capstan motors you get in VCR's, no brushes etc.
> ...
>Hmm, good starting point would be dry joints and electrolytics, then the
>3 x TIP100 and 3 x TIP105 Transistors, then the motor control IC.
>Can't quite see what that is yet.
Sounds like a pretty standard brushless DC motor. The coils are energized
in sequence to turn the blower at a desired rate. Presumably there is also
some sort of feedback mechanism to tell the controller IC how fast the
blower is turning.
My guess is that one or more of the transistors are blown and thus you need
to replace them. Another possibility is of course the controller IC but
that seems less likely to me for some reason.
--Chuck