dimmer buzzes as light increases

[Janet_1967]

Hello all,
I am new here, but DID read through posts first.
I seem to have the opposite problem to most.
I rewired a standard 1 gang light swith to a dimmer from well known UK DIY store..brass effect at around 10 pounds if that makes a difference.

Tonight on coming home, my daughter said it was humming-
The humming comes from the light itself--a ceiling fan type light with a 100watt bulb presently(we both study) but reduces on dimming.

I appreciate it could be the increased current but is there anything I can do please?

Thanks,
Janet

 

[EddieCurrent]

Does the light fitting hum when the fan is switched off ?

 

[jj4091]

is there anything I can do please?

Thanks,
Janet

Put the swich back on

 

[Janet_1967]

Haha jj...

James, The problem of humming is when the light is at full capacity(ie brightest)
just tried the fan and it works, and strangely, on turning fan off-the buzzing has also stopped---wierd

will see how it works at night

Cheers anyway.

 

[EddieCurrent]

The dimmer switch is also controlling your fan.Thats where the noise is coming from.
This may affect the lifespan of your light and indeed the new dimmer switch.

 

[Adam_151]

Its also not going to be good for the fan or the dimmer, please change it, you could overheat something and cause a fire

(I'm sure if your read the instructions for the fan it'll say not to fit to to a dimmer)

 

[Janet_1967]

sorry--James is not James but Eddiecurrent(apt ) dont know where I got that from!

re fan--dont like it anyway-I will put new light in--I am sure box would have said that, but its been up about 12 years..lol

Have to say--fab site..I am not an electrician either but done a large module in building, electrics, gas etc as part of BSc Env Health.-

Janet

 

[EddieCurrent]

Hello Janey,

Your new dimmer switch should have it's 'rating margin' written on it somewhere on the reverse side, keep this in mind when you pick another light fitting, or you may end up having to take it back ,and exchanging it for one that is suitable for the new fitting ! ( more hassle) .
Some fittings, as you now know, are not able to be dimmed too.

Hope this is of some help.

 

[jj4091]

Haha jj...

I was not joking, you did not say you were going to instal a new fitting

 

[Janet_1967]

no I know you wasnt, but I dont want a normal switch--hence my eyes rolling

Janet

 

[bernardgreen]

Does the fan / light unit have a pull cord for the fan on/off function

If yes and the ceiling rose is wired normally the fan then it may be possible to re wire the fan / light unit so that the fan is feed from the permanent live and thus controlled by the pull cord and only the light is connected to the switched live from the dimmer.

 

[Steve]

Did you buy the cheapest dimmer on the shelf? These are prone to "strange" faults like intermittent humming. The best ones are those "touch-and-remote-control" ones that you walked past on the way to the cheap ones. Expect to pay £30 for a brass 'un. Very good kit though, practically silent (only audible when you get up close).

 

[speedfreekz]

Cheap dimmers buzz. This is because the components inside the dimmer are of a cheap quality but it is quite safe but can be annoying

The reason why your fan is buzzing if connected to the dimmer is because it is not getting the required voltage necessary to work, filament lamps are much different to a single phase motor, which is basically your fan.

The buzzing noise from the fan is the motor, from what i said the way the dimmer works is by breaking the AC sine wave at a selected point, determined by the thyristor setup which in turn reduces the voltage. The effect in a filament lamp is a dimming effect, the effect of other electrical appliances is the risk of malfunction.

Remove the fan from the dimmer, keep the light attahced, all the buzzing you will recieve then is from the dimmer itself ( cheap components)