HELP: How to get rid of the spike

[Mr. Edwin KwanTo Tam]

Hi,

I had installed a electronic dimmer to my ceiling lamp but because of the
AC power line is also connected to two ventilation fans, whenever I switch
off the fans, the spike produced by the motors affect the dimmer;s operation
and eventually brun the (Thyristor) off.

I'd like to know what can I do to prevent the spike from damaging the
(now newly installed :-) dimmer, and I'd prefer the add-on device is on the
dimmer side.

I heard about voltage limiting resistor, but don't know how to use it.

Thanks for your help.

Appreciate email response.

Edwin Tam

[Don Montgomery]

Mr. Edwin KwanTo Tam (edwi...@hk.super.net) wrote:

> I'd like to know what can I do to prevent the spike from damaging the

You might try a snubber consisting of about 100 ohm/0.5w resistor in
series with 0.1 uF/600V capacitor in parallel with the main terminals
of the dimmer's triac.

-- usual disclaimer, etc. --
Don Montgomery
do...@sr.hp.com