Andrew Gabriel wrote:

In article . com,
"paulfoel" writes:
Andrew Gabriel wrote:
The capacitor is easy to test. What rating is written on it?
Assuming it's a mains one, connect it in series with a mains
light bulb (something between 40W and 100W), and the light
should come on, but not as bright running directly off the
mains. Beware in case the capacitor case has become live in
some internal failure.

However, the nature of the fault you describe sounds to me
more like a broken motor winding. Capacitors don't usually
fail intermitently.

8 micro Farrad

So that's an impedance of 398 ohms at 50Hz, so a 60W 240V lamp
in series should be around half brightness if the capacitor is
working. If it's not working, lamp will be fully on or fully
off (depending on the capacitor's failure mode).

If you need a new capacitor, one source would be an electrical
wholesaler, who will stock them as power factor correction
capacitors for fluorscent fittings and HID lamps.

Actually, just checked CPC catalogue, and there are a few
designated as motor run capacitors...
CA00003 @ £3.95 (metal case, 1/4" tabs),
CA00010 @ £3.35 (plastic case, 1/4" tabs),
CA00019 @ £3.65 (plastic case, flying leads).
All these are 8µF, 440VAC (which is fine for mains),
with a mounting stud on the base.

--
Andrew Gabriel

Whats the difference between a motor run and a motor start capacitor ?