buzzing dimmer switch

18 Aug 2008
Reaction score
United Kingdom
Just wondering why a dimmer switch makes a buzzing sound, the light it feeds is dimmable and contains 3 x 28w g9 bulbs (not sure if dimmable bulbs or not), the dimmer switch is 400w rated.

Buzzing is loudest just at the start of dimming and when the lights are at lowest intensity, there is some flickering.

Any ideas? Bulbs perhaps?

All connections look find.
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It's probably the little transformery thing inside. You bought cheap. Get rid and put a switch in they don't buzz.
I suppose those 28w g9‘s are 230V halogen?
If so they are dimmer-able.
As Pete says, it’s the dimmer that’s the issue. The total load is only 84W so I also suspect the load isn’t quite big enough for quieter smooth dimming.

Get yourself a better quality dimmer with a lower power spec, not more than 250W and you’ll probably be sorted.

One of these is your option.
Pete I bought dear, £11.99 at wickes, I really need to stop shopping there because it's so sh1t, but local.

Taylor, they are halogen and not LED, thought there may a dimmable and non-dimmable version of the halogens..

resent having to modify this switch in any way, especially since they fuked me up already by telling me it was in stock when it wasn't, and a wasted journey later I find it's even more trouble.
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Dimmers buzz due to the combination of the chopped waveform and inductance.

Just looked at that one on Wickes, and expensive though it is, it's a leading edge dimmer which generates some noise.

A trailing edge dimmer is more expensive but quiet.

One of these is your option.
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Halogen lamps shouldn't really be dimmed either but lots of people do it. Doesn't make it right though.
Sorry I meant to say module not transformer, got my terminology mixed up

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