"Donwill" popple @diddle .dot wrote in message
...
Thanks for that, what I'm really looking for is information about the
fan
motor, since it's got 3 leads going to it, a red, blue and a white, and
as I
said before the white lead is terminated with an insulated crimp
connector
which is not connected to anything. I suspect the manufacturers
(Silavent
SVC6) use an universal 2 speed motor which can be used in one speed or 2
speed mode. I'm guessing that if I connect the white and blue across the
mains and disconnect the red it will run at a lower speed but I 'm loath
to
try it.

On the back of the installation leaflet it has the following info :-

230V- AC. 50Hz
High speed /Single speed 35W
Low Speed 25W

Don

why not check it with a multimeter, and if it fits what you suspect,
try running it in series with a lightbulb. At your own risk.


Good idea, I'll try that when I'm a bit more awake.
Cheers

Ok I've measured the resistance of the windings and they are as follows :-

Starting at the top draw two resistances in series vertically one above the
other. Now you have 3 wires connected to the network, a red one at the top,
a blue one as a centre tap, and the white one at the bottom.

DC Resistance, red to blue = 278ohms.
, blue to white = 80 ohms
, red to white = 358 ohms
The red and blue wires disappear into a printed circuit, the white is
floating and insulated.
My thought is to connect a changeover single pole switch (break before make
?) as follows :- common connect to pc where the blue went.
c/o1 blue, c/o2 white.

Any comments appreciated.

Don