GU10s to LED

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rs6mra

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I currently have GU10s which are 50watts each x6 installed in a bathroom and would like to change them to these LED lights
The GU10s are all on dimmers and I would like to know if this is notifiable. It seems pretty straightforward to me but it might not be the case where electrics are concerned.
 
Can you not just change the bulbs rather than the whole fitting? You might have to change the dimmer as well as some dimmers don't like leds
 
Having been through this many times with the early LED bulbs I would buy a couple and try them. While they have improved it is still hit and miss with dimmers especially the older ones.
 
No problem just changing the bulbs just make sure you buy one suitable for dimmers or change the dimmer switch in the bathroom for a standard switch.
I replaced every bulb in our house with LEDs including both bathrooms. and they've improved dramatically, even the cheapos are half decent these days though I buy decent quality bulbs online. They last a long time as well which is a bonus.
 
Also bear in mind that some dimmers don't work well with LEDs, but, IIRC, the ones that are designed for LEDs are also compatible with incandescent lamps.
Some "modern" dimmers allow you to set minimum and maximum brightness levels, which is great unless you have resident grandchildren who keep accidentally putting them into setup mode.
 
Wall plate dimmers are invariably of the "phase control" type - they are cheap & cheerful and essentially vary the power delivery from 0% to 100% for an incandescent device like a halogen bulb.

LEDs do not dim - they are either ON or OFF (they don't dim) - you get the ILLUSION of dimming by using PWM, Pulse Width Modulation, where the LED is switched VERY rapidly on for say 10% and off for 90% which gives the ILLUSION (as your eyes have persistence of vision) of a 10% bright LED. LEDs therefore generally need PWM rather than phase control dimmers.

You can easy see the rapid on/off switching of LEDs by spreading out your fingers in front of your eyes and shaking your hand up and down - the fingers will appear to "freeze" just like in a old strobe light - LEDs turn on and off immediately as they are solid-state devices and have no thermal lag (unlike halogens).

Some modern LED units are smart enough to interpret phase-control and change that internally to PWM, but it's a nasty hack. Just do a proper job and change the dimmers to PWM as well.

PWM dimmers should also work with incandescent bulbs.

Except in the showers, I replaced all our MR11/MR16 lights (52 of them) with 230VAC GU10 LEDs and removed all the transformers (nasty things, unreliable). It's worth noting that LED MRxx bulbs often have real problems with electronic 12V "transformers" as the electronic 12V transformers often require a minimum current draw to work correctly and a LED replacement may be 5W instead of 50W, so the bulb may not light at all, flicker on and off, or "sing",
 
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You can buy 12V GU10 LED light bulbs that can dim, so a straight forward replacement of the bulbs.
I personally dont like sealed for life lighting units. When one goes, unless you can still buy the same model, your back to replacing all the down-lights to get them to match for one bulb that’s gone!
 
Ansel downlights have a pretty good reputation with dimmers, but like all LED's they can have issues with 'some' existing dimmers- it really comes down to 'try it and see'- if they work with your existing dimmers- all's good, but be prepared to replace the existing dimmers as well if they don't play nice together...

Just a fact of life, older dimmers aren't all identical, and some work differently to others and may not simply work as intended when they were designed for a certain load and lamp type, and are now being being used with a different type...

That said, many cheaper brands of dimmable LEDS are pretty bad themselves and are very 'touchy' about what dimmer they are used with, Ansel is one of the better brands in this respect...
 
I don’t think I can change the bulbs as the ones there now are 12v and have a transformer
May be talking out of turn but AIUI GU10 bulbs normally run at 220-240V. I would not expect them to need a transformer to drop them to 12V.

GU10 LED normally have circuitry built in to allow direct replacements with a traditional 240V GU10 and should not need a transformer.

Question - as you apparently have a transformer, are the existing bulbs GU10 or MR16. The latter, which have a similar appearance (bar pins for connection), did need a 12V supply.
 
A bathroom is a special location in terms of wiring regulations for electrics.
Damp / water increases the risks of electrocution.
As Terry says immediately above, are you sure your lamps are GU10 not MR16, as GU10 are a 240V lamp with a transformer built in, not a separate transformer.

If you have low voltage halogen lights fed from a separate transformer, that installation is lower risk than 240V. Replacing 12v low voltage halogen with LEDs powered from mains is an increased hazard and depending where they are, you shouldn't do it.

Read this
https://www.thelightingsuperstore.co.uk/bathroom-lighting-zones
 
I've just done this update on my bathroom, changing 12V MR16 halogens to GU10 LED'S. I had to buy GU10 bulb holders, which are readily available from the likes of Screwfix. The only problem I encountered was that the GU10s with bulb holder were a little taller than the MR16s and fouled the top frame of the housing. Fortunately this frame could be easily reshaped to provide the enough clearance.
Did the same exercise on the kitchen lights where dimmers were fitted but decided to ditch them in favour of simple on/off switches.
Brian
 
Get some dimmable mr16 led plug in replacement bulbs, those should work fine with no need to alter the wiring.
Buy 1 to try it before you swap them all.

Something like this maybe - just as an example
https://www.lightingstyles.co.uk/mr16-osram-advanced-65w---dimmable-led

I used to buy non dimming osram mr16 leds from my supermarket. They make a good lamp.
 
Get some dimmable mr16 led plug in replacement bulbs, those should work fine with no need to alter the wiring.
Buy 1 to try it before you swap them all.

Not quite... As I mentioned above:

" It's worth noting that LED MRxx bulbs often have real problems with electronic 12V "transformers" as the electronic 12V transformers often require a minimum current draw to work correctly and a LED replacement may be 5W instead of 50W, so the bulb may not light at all, flicker on and off, or "sing".'
 
Yes, I was being bullish, there is a risk as you say, but the linked retailer is offering

"This is a dimmable lamp. We have not had any reports of issues when dimming this lamp on UK dimming equipment.
If you do encounter any problems we will give suggestions on what dimmer module may perform better or offer a full refund on lamps returned to us in a saleable condition."
 
GU10 is a common bulb these days, General Use with pins at 10mm spacing and can be used in any location but I will add that I dislike down lighters anywhere, all those holes in your ceiling. As already mentioned a bathroom is classed as a special location and the main thing to bear in mind are the zones within a bathroom which dictate what can and cannot be placed there. The best advice for you is to get a qualified electrician in to ensure everything is safe because one question that has not been asked is where are the dimmer switches located ? If it is a pull cord dimmer then great but a wall mounted switch in a bathroom !!
 
Thanks guys. I can confirm that the dimmer switches are outside the bathroom.
I anticipate that this will all change in the next 12-18 months are everything will be renovated. I just wanted to get through this next few months with decent lighting in the bathroom especially for when I shave and in addition it winds me up that this bathroom is shared with one of my daughters' who never turns the damn lights off.
 

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