Dimmer switches with LED bulbs

phillsmit3 · Post by **phillsmit3** » Tue Apr 28, 2020 8:07 am

Just a quick query.

With normal dimmer switches that say not compatible with LED is this normally just because of the minimum load rating? (for example 60W minimum load rating)

I am replacing my 16 x 25w candle bulbs that are on one dimmer switch = 400W
with 16 x 5w Dimmable LED candle bulbs. = 80W

My question is this. Because 16 LED bulbs brings the total wattage to 80W and this is above the minimum load rating should everything be ok?
I'm thinking the manufacturers assume that most people won't use as many was 16 bulbs so therefore just say it is not suitable for LED bulbs.

any help would be great.

Thank you.

Someone-Else · Post by **Someone-Else** » Tue Apr 28, 2020 10:21 am

There is more to it than that.

First of all there is the type of dimmer switch, leading edge or trailing edge, without going technical, you need a leading edge dimmer switch (Most are trailing edge)

Then there is the question of the LED lamps again without going technical, most LED lamps can NOT be dimmed, it will say on the packet if yours can, if it says nothing, they can not be dimmed.

Lastly, do you really want to?
Old incandescent lamps change colour as they are dimmed, they go from a bright white to a orangey yellow, LED lamps do not do that, they really do just get dimmer.

In conclusion.
Find out can the lamps you have be dimmed, check the dimmer switch to see is it leading edge, if either is no, then you will have to change which ever or all, if one is wrong, you risk destroying both (Doesn't explode, just goes fsssst, puff of smoke, although it may go BANG! and no smoke)

ericmark · Post by **ericmark** » Wed Apr 29, 2020 11:00 am

someone-else wrote: ↑Tue Apr 28, 2020 10:21 am There is more to it than that.

First of all there is the type of dimmer switch, leading edge or trailing edge, without going technical, you need a leading edge dimmer switch (Most are trailing edge)

Then there is the question of the LED lamps again without going technical, most LED lamps can NOT be dimmed, it will say on the packet if yours can, if it says nothing, they can not be dimmed.

Sorry it is the reverse, the EU and we adopted all the rules before we left, stated it must say if NOT Dimmable if it is dimmerable it does not need to say anything, although normally it will.

someone-else wrote: ↑Tue Apr 28, 2020 10:21 am
Lastly, do you really want to?
Old incandescent lamps change colour as they are dimmed, they go from a bright white to a orangey yellow, LED lamps do not do that, they really do just get dimmer.

In conclusion.
Find out can the lamps you have be dimmed, check the dimmer switch to see is it leading edge, if either is no, then you will have to change which ever or all, if one is wrong, you risk destroying both (Doesn't explode, just goes fsssst, puff of smoke, although it may go BANG! and no smoke)

I have electronic switches, not dimmer switches but still electronic which do not require a neutral, the spec says minimum wattage of 5 watts, however a set of 5 x 2.2W G9 bulbs would not switch off until a load capacitor was added, and then they would get an annoying flicker, not all the time, it seemed what ever we did it would stop it, then it would return, in the end we had to change one bulb to quartz tungsten and then the flicker went. The manufacturer of the switch do a list of bulbs that should work OK. If you look at the list, most of the bulbs are expensive. A "Philips Master g9 bulb" on Amazon £7.87 with other makes you can buy a pack of 6 for the same price.

I find LED lamps last a long time, I have had one bulb fail and one tube fail, and been using them in three houses for around 4 years now, so I don't keep packs of LED bulbs in the house like I did with old tungsten, so when one does blow I want to pop to local shop and buy one, not have to order special over the internet, as normally I want the replacement today, OK at moment different, but if your lights need a special bulb it causes problems when on goes.

Amazon Basics Candle is on the list for bulbs for use with my electronic switch, but if you read the review the first questions is "Do these require a leading edge or a lagging edge dimmer to work correctly?" the answer is "They flicker regardless not the best bulbs" to be frank likely most of the bulbs come from same factory in China and just have different badges, but flicker with LED bulbs and electronic switching is the main problem, and I am sure it is something in the switch not the bulb which causes it, I have two chandelier one with 6 and one with 8 E14 LED bulbs from Home Bargains switch with electronic switches which say non dimmable which all work A1. It is like a lottery, suck it and see.

There are a number of methods to power an LED within the bulb, the simply way is to use a capacitor as a current limiter, plus some bleed resistors, this allows dimming but it also means there is a capacitor which can affect the electronic switch, the other method is a pulse width modulated electronic driver, often it turns the AC to DC and smooths it first, they have a very high frequency flicker which a human can't see, not the 100 Hz found with cheap methods, and auto compensate for voltage variations, but they can't be dimmed.

phillsmit3 · Post by **phillsmit3** » Mon May 11, 2020 10:18 am

Thank you for all your help. It all seemed a little complicated so I ended up getting a philips LED bulbs as they do a chart showing compatible dimmer switches.
Interestingly the dimmer switch that Philips said was fine and i went for was a standard dimmer switch that said not suitable for LED lights on the manufacturers website.
It works perfectly.

Maybe it is some Philips wizardry?

ericmark · Post by **ericmark** » Tue May 12, 2020 3:06 pm

I was persuaded by my wife to change the four down stairs light fittings for matching chandeliers two with 5 bulbs E14 and 2 with 3 bulbs again E14 and we bought 16 Philips 8W CFL golf shaped bulbs for the new lamps at £5 per bulb, we were told the bulbs should last 10,000 hours which would at our usage equate to around 6 years, 18 months latter only 5 bulbs were still working, the replacements for Home Bargains slightly bigger physical size also 8W were still all running 3 years latter when we swapped to first 3W and the 5W candle LED bulbs, both the 3W and the 5W LED were brighter than the Philips bulbs, from then I have avoided Philips bulbs, they were considered as high quality, but seems they started having them made in china and the price is still high but the quality is not.

I now buy from Home Bargains, B&M Bargains and Lidi and have had no failures from them, have had G9 bulb fail and a 5 foot replacement for a fluorescent tube fail but they came from electrical whole sale outlets. I now always look for the cheapest bulbs on the high street as they seem to last longer.