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Dinner switch making hum noise

U have just had dimmer switch installed and it seems to be making hum noise when the dimmer is turned on and noise stays on. Light fixture has led dimmable bulb.

I don't have this issue with dimmer switch in other room, (it's different make dimmer switch in both rooms).

I asked the electrician who fitted and he advised that it is quite common for hum noise from dimmer switch.

Is the dimmer switch faulty or is it normal for dimmer switch to make hum noise.

Normal switch was installed before it was installed with dimmer switch.

3 Answers from MyBuilder Electricians

Best Answer

Matching led dimmers with led can be challenging , yet with the trailing lead dimmers mostly, humming can be a problem . It can be fixed quite simply by matching the correct load to the correct dimmer . Trailing edge dimmers are the best to use with led loads , yet you should be aware slight humming can arise if you haven’t matched the correct load to the design of the dimmer . I use varilight dimmers , the LEDLite gives a good all round performance allowing up to a 150w load , down to 0w . Good luck


Answered 20th Jan 2020

A humming dimmer generally indicates that the load(light/lights) being dimmed is not suitable/compatible for the switch. The fundamental point is older dimmers were designed to dim incandescent/halogen light type lamps which would have a higher load (wattage), these type of dimmers would generally have a 250w/400w max loading. Nowadays, assuming dimmable LED lamps have been fitted the load would be expected to be no more than 100-150w max and a quality trailing edge dimmer unit should be used. Some LED dimmers have an adjustable pot to give optimum performance depending on the load/number of LED lamps that require to be dimmed.


Answered 22nd Jan 2020

Previous answer is good, if you want completely noise free dimming you will have to install a Zano Dimmer, but they don't come cheap, they are especially developed for LED fittings/lamps and you can set the minimum dimm level as they are programable. around £35-£40 plus VAT from most good electrical wholesalers


Answered 1st Feb 2020

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