Way to smart up normal downlights?

(Simon C) #1

Hope you guys can point me to the right direction. I searched and read - there is a thread about switches but not quite what I need.

I have pretty much all the lights set up except the two bathrooms that have LED downlights with transformer that don’t work with GU10 (transformer) and don’t want to mess with the electrics as not that familiar with wiring etc

Now what I really want is a switch that can work on either ST (preferred) or other hubs (I have several devices from harmony to Hue being my first - mostly linked to Alexa) so that I can utilise the ST sensor that came with the pack. Ideally I could dim with in wall switch or app tho secondary. But I would like to have the motion sensor detect either door opened (with a door sensor in the pack) or better still with the motion sensor so that It trigger the switch to turn the lights on when you walk in and if no further movements for say 5-10 mins they switch themselves off.

The lights are on one circuit with just two wires in the switch I believe and the lights are LED dimmable ones and not smart…obviously.

Any recommendations will be greatly received.

Thanks in advance.


(Robin) #2

Go for a Fibaro Dimmer 2 micro module behind your existing switch.

It’s the only UK dimmer module that works on two wires. It’s also a great device, compatible with dimmable transformers and works really well… I have my whole house fitted out with them!

If you want the ability to dim from the switch, replace your existing switch for a momentary (retractable) type.

(Robin) #3

There are countless smartapps that can convert sensor input into switch automation.

For motion turning a light on for a set time, the easiest option is ST’s own smart lighting app.

For more complex rules you should look into the CoRE smartapp which can basically do anything you can think of!!

(Simon C) #4

Ah I did come across on here that but wasn’t sure How it works so will look into it.

May I ask is it the micro 2nd edition like this one

Or the black ones by Fibaro FGD212 like this one

I must say I dismissed it cos I looks way too big to fit within a switch :slight_smile:

As with the LED dimmer, I can therefore just that the standard LED one like this one? And let the fibaro do work with the sensor?


Again thanks for your swift response and recommendations! Really appreciate it!


GU10 bulbs don’t use a transformer. They just run off 240V.
MR16 use transformers as they run on 12V
If you have GU10 / MR16 housings, you could use Hue GU10 bulbs

(Robin) #6

The Aeotec is very different to the Fibaro.

Main difference is that the Fibaro Dimmer 2 will work on your two wires, Aeotec won’t.

Micros won’t work with normal dimmer switches, best with momentary switches.

Micros are a lot smaller than you think… photos are misleading.

Vesternet is often a better source for kit in the U.K. and has lots of handy guides.


(Chris Nelson) #7

Fibaro dimmer 2 module is what I used recently which was installed at the light switch. I have MR24 down lights I think and Philips hue don’t have anything smaller than GU10. It works fantastic.

(Simon C) #8

Thanks soooooo much for all the helpful information!

Sorry, i probably didn’t make it clear - I bought a whole loads of Hue GU10 and some fittings but i just causally ignored the fact that they needed to be IP65 as it’s right above shower - also the transformer (I believe to be 150-200 watts?) requires relatively high wattage X4 to get through the minimum load threshold) - anyway, even if my concept of it is utterly wrong, it has been agreed that those relatively new downlights are not to be replaced end-of…I have been sternly told…(luckily I can still use the GU10 bulbs downstairs in the kitchen - eat my shorts!!)

Will order the dimmer 2 module from Vesternet now.

and I have located a retractable switch locally on screwfix!! Not sure if it dims (would it be a 2-way one? such a noob with electrics…) (but i can always do it on app - and it’s only £3…

Thanks again, Robin, Steve and Chris for your help.

Will look at ST’s own app once i have the switch set up - one step at a time…


(Robin) #9

You only need a 1-way momentary switch (but they normally come in 2-way which won’t hurt, just don’t use the L2 terminal).

You will have full diming function with a momentary switch. Recommend you get a double switch (2-gang) as you could then take advantage of the scene ID (1x, 2x, 3x Click, hold and release) feature.

More info on switches and scenes here:

(Simon C) #10

Oh mine…just saw your even more useful info - that would have been perfect to use.l…

Wife approval tactics:

1: Make sure everything works the old fashioned way using physical wall / cord switches.

2: Be discrete on the cost.... 
Her - "How much did that cost?" (£48 Fibaro)..... 
Me - "errr.... I got a deal, it was £15 love"

3: Pretend you know what you're doing...
Her - "Be careful with those electrics"
Me - "Don't worry babe, it's just the low voltage side"

4: Make all your automations benefit her, not you!

5: If she doesent like that camera in the shower, hide it!

exactly what I needed! too late now.,…

(Robin) #11

I think I was drunk when I wrote that lol!

(John) #12

Does anyone know if the FGD-212 works with flourescent tube strip lights? I have one in my utility room that I can’t switch to a hue bulb so this solution would be ideal.

(Robin) #13

Yes, but only in on / off mode (dimming disabled)

I have two tube lights in my garage running on a dimmer 2

(John) #14

Perfect! Thanks Robin.

(David Jacobs) #15

What happens If you use the Fibaro in an 12 light LED GU10 circuit which has a mix of dimmable and non-dimmable bulbs (Basically I replaced the blown dimmable with non-dimmable to save you asking why theres a mix). Will it screw up?

(Robin) #16

It won’t screw up… but you won’t be able to use the dimming functions without flicker.


Just to add to this, the Fibaro dimmer won’t work if there is too little draw of power from your lights, it needs to be around 180w at least I have found, so I had an issue with LED downlights as they were about 10 x 4w so it would not work, and its a pain if you have spent money replacing all your bulbs with LED’s.

Also, all lights on the switch must be same, so you can’t have a combination of different bulbs or different LED chips (trailing edge v leading edge).

(Robin) #18

Actually, you can have as little as 5w if you use a Fibaro bypass module wired across the load.

Also, I have a setup with different loads and it works just fine (2nr 240v halogen spotlights, 2nr 240v LED spotlights and 5nr 12v LED under counter sports via transformer, all via one Fibaro dimmer (in on/off mode - dimming disabled).

Trailing / leading edge only applies when using the dimming feature and actually doesn’t make much difference for most loads (except maybe compact fluorescents).


True, that can be quite difficult to fit though

(Robin) #20

It’s easy, just wire across L & N behind the main (first) light fitting. Takes minutes.

Also, without the bypass, the minimum is 50w not 180w. :wink: