Buzzing light switch

[Mark Carver]

I just noticed today that the light switch in my garage was buzzing at

100 Hz when the lights (3 x 40 watt fluorescent tubes) were on. It is a 2-way switch ganged to another, that one does not buzz, but the 'duff' switch buzzes in either position if 'on'. I've replaced the switch with another I had kicking around, that also buzzes but to a much lesser extent.

What is going on, for the buzzing to be at 100 Hz there might be a rectifying effect somewhere inside the switch ?

[bigcat]

'duff'

if a plain vanilla on/off switch buzzes its an immediate fire risk.

NT

[markzoom]

A sinewave produces one positive and one negative peak per cycle, hence 100hz instead of 50hz buzzing. If your switch is noisy it's not making a proper contact and should be replaced or fixed. M.K.

[Mark Carver]

Doh ! of course, obvious if I actually think about it properly !

Will do today as soon as B&Q open !