Dimmer switches for ceiling lights

katejo

I am in the process of choosing new lights for my living room and would like to have a dimmer switch. However, I have been told today by a friend that these can fail quite quickly. Her ones died within a year. Has anyone else had the same experience?

Bendy_House

Dimmer switches should last years with no issues.

You do need to ensure you buy ceiling lights which are SUITABLE for dimming, of course, as not all are. And also the correct RATING of dimmer switch to match it - that would also include whether they are LED lamps, low voltage, etc.

So I'd suggest the best sequence would be to choose the lights first, ensuring they are dimmable, and then the dimmer switch to suit.

If you'd like to post on here the lights you are considering, then we can advise further. 

Although dimmer switches 'will' tend to wear out before standard types, that will depend a lot on how much they are used - rotated - but they should last years in any case.

Belenus

We have had a number of Varilight V-Pro dimmer switches that have proven to be very reliable for many years. They are also virtually silent and don't hum like many cheaper dimmers.

We normally buy them from Screwfix but they are widely available elsewhere.

Make sure you get the correct wattage rating and read up on the difference between leading edge and trailing edge dimmers.

katejo

Bendy_House said:

Dimmer switches should last years with no issues.

You do need to ensure you buy ceiling lights which are SUITABLE for dimming, of course, as not all are. And also the correct RATING of dimmer switch to match it - that would also include whether they are LED lamps, low voltage, etc.

So I'd suggest the best sequence would be to choose the lights first, ensuring they are dimmable, and then the dimmer switch to suit.

If you'd like to post on here the lights you are considering, then we can advise further. 

Although dimmer switches 'will' tend to wear out before standard types, that will depend a lot on how much they are used - rotated - but they should last years in any case.

Yes I know to choose the lights first. I haven't had much success yet. I am frustrated by the way in which many light suppliers are online only. I want to see the lights (switched on)  myself. The ones which I did see were labelled as suitable for a dimmer switch and needed LED lamps. 

Bendy_House

The Varilights, as mentioned by Belanus, seem to be a reliable go-to for these.

'Click' also do decent ones - they have a nice smooth feel in use.

Mains LEDs are usually happier with 'trailing-edge' dimmers rather than 'leading'. Again, when you finally find 'your' lights, see what it says. 'Trailing' are much less likely to flicker, and some LED lamps need them.

katejo

Bendy_House said:

The Varilights, as mentioned by Belanus, seem to be a reliable go-to for these.

'Click' also do decent ones - they have a nice smooth feel in use.

Mains LEDs are usually happier with 'trailing-edge' dimmers rather than 'leading'. Again, when you finally find 'your' lights, see what it says. 'Trailing' are much less likely to flicker, and some LED lamps need them.

What do you mean here by 'trailing edge' and 'leading' dimmers please?

Bendy_House

katejo said:

Bendy_House said:

The Varilights, as mentioned by Belanus, seem to be a reliable go-to for these.

'Click' also do decent ones - they have a nice smooth feel in use.

Mains LEDs are usually happier with 'trailing-edge' dimmers rather than 'leading'. Again, when you finally find 'your' lights, see what it says. 'Trailing' are much less likely to flicker, and some LED lamps need them.

What do you mean here by 'trailing edge' and 'leading' dimmers please?

It's just the way they work in order to reduce the voltage to dim the LEDs. You don't need to know what this involves, but only that SOME bulbs are sensitive to this.

For some reason, 'leading' dimmers are usually cheaper, but 'trailing' is smoother.

(You know that AC voltages constantly change, 50 times per second in a sine wave form? The upwards slope of the wave is the 'leading' one, and the falling slope the trailing. Dimmers work by reducing the voltage in steps, and that can be on either slope. For some reason, stepping the upwards - leading - edge disturbs some LED lamps, and they can flicker and misbehave in other ways too. That's a crude description - 'cos it's pretty much all I know...)

Choose you light fittings and suitable bulbs first, read what it says about them (no of watts, how many actual bulbs to each dimmer, and if 'trailing' is mentioned), and then choose a dimmer to suit.

Most dimmer switches will also have a MINIMUM power rating as well as a MAX amount they can handle. If the LED bulbs don't add up to the MIN rating, the dimmer might not even work at all! And if you exceed the MAX - unlikely with LEDS - then you can blow the dimmer.

This isn't all as hard as it sounds! A dimmer that states it is DESIGNED for LEDs, will usually be fine. And more and more LED bulbs will now handle both 'edge' types. But, it is worth checking.

Chickereeeee

You may be disappointed in normal, dimmed led lights. Tungsten lights get 'warmer' as they are dimmed, whereas most led lights keep the same colour temperature. Phillips (and I guess others) do led lights that also give a 'warmer' light when dimmed, and work well. 

Bendy_House

Chickereeeee said:

You may be disappointed in normal, dimmed led lights. Tungsten lights get 'warmer' as they are dimmed, whereas most led lights keep the same colour temperature. Phillips (and I guess others) do led lights that also give a 'warmer' light when dimmed, and work well. 

Very good point.

I use only Philips 'Warmglow' (they have another name too, what is it?), and they are truly superb. Just indistinguishable from incandescent bulbs.

They come in GLS size, a slightly smaller GLS, 'candle' size, and I think golfball. Not sure if they do the wee capsule size?

Look carefully on eBay and you can get them for around £4 each (or used to...)

Just brilliant.

'Dimtone' is the other name, I think.

Ectophile

katejo said:

Bendy_House said:

The Varilights, as mentioned by Belanus, seem to be a reliable go-to for these.

'Click' also do decent ones - they have a nice smooth feel in use.

Mains LEDs are usually happier with 'trailing-edge' dimmers rather than 'leading'. Again, when you finally find 'your' lights, see what it says. 'Trailing' are much less likely to flicker, and some LED lamps need them.

What do you mean here by 'trailing edge' and 'leading' dimmers please?

The AC mains is a sine wave.  A dimmer chops bits out of that sine wave, to reduce the brightness.  One type chops the bit out of the beginning of each wave, the other chops it out at the end.  It's easiest to understand with pictures, as shown here: https://www.electricalcounter.co.uk/types-of-dimmer 

Most LED lamps don't like leading edge because of the sudden rise in voltage at the point in each waveform where it's switched on.  The sudden surges 100 times a second plays havoc with the electronics.  Trailing ones are friendlier to the electronics.

Traditional dimmer switches for tungsten filament or halogen lamps are leading edge, because they are simple and cheap.

FaceHead

Agree that cheap dimmer switches are rubbish, and fail and/or hum. This probably explains your friend's experience, OP.

Overall, however, I'm not a fan of dimmer switches.

I think you should simply have appropriate lighting in the room. Appropriately bright ceiling lights for how the space is used - not to put excess downlighters in like builders love and make a cozy lounge into a stage. In cozy areas perhaps have a lamp as well as the ceiling lights, and put more ceiling light in work spaces like kitchens and offices.