The GU10 and the MR16 are the main two spotlights used in the home today. Most people have them in their kitchens and/or lounges and unfortunately the existing halogen spotlights are incredibly expensive to run. Both types of spotlight are pretty similar in appearance but underneath the bonnet they are fundamentally different.
The main difference is that the GU10 bulb will run at 240 volts (which is the same voltage as supplied by the mains power supply), while MR16 bulbs run on just 12 volts.
As a result MR16 bulbs need an external transformer to convert the buildings main 240 volts mains supply to the 12 volts required to run the bulbs. With GU10s, you can simply plug in and you are good to go.
Retrofitting LED spotlights in your home
Halogen spotlights normally run at 50watts while their LED cousins run at just 5watts. Therefore it is certainly worth replacing them since you can produce massive savings on your electricity bills by doing so.
>>> Find out how much you could save by making the switch <<<
The first thing is to determine the type of spotlight you have in your home – you can use our diagram below to determine which one you have.
So you have GU10 Bulbs…
If you have halogen GU10s firstly give yourself 10 seconds to feel smug – the LED bulbs will work perfectly straight out the pack and give you savings of over 90% on your energy bills.
The only thing to ensure is that you buy dimmable LED GU10s if you have a dimmer switch or non-dimmable if you have a normal switch in your home.
So you have MR16 bulbs…
Installing LED MR16’s is much less straightforward, however it is still a worthwhile process since replacing six halogen 50watt bulbs with six 5watt LED bulbs will result in substantial savings over a very short space of time (they tend to pay back in a little over a year despite being 10 times the price!)
Now the older magnetic transformers will work perfectly with LED MR16s. The issue is that the electronic low voltage transformers may not. The reason for this is that they need a minimum voltage to pass through them to operate; for example the transformer in my kitchen is 40w – 400w. Historically there were 6 50w halogen bulbs in the circuit – giving a total load of 300w.
Replacing those 50w halogen bulbs with 5w LED equivalents will put a load through the transformer of just 30w in total. Therefore this means the transformer won’t work correctly and will probably result in your LEDs flickering. In this instance you need to replace the existing transformer in the circuit with an LED driver/transformer that is matched to operate on the total number of watts in your circuit.
Final thoughts – GU10 versus MR16
Now, in terms of ease, you can actually buy a GU10 LED bulb + a brand new GU10 fitting for just over £20 – so you can then ignore the MR16 transformer issue completely. However regardless with how you want to move forward, moving to LED bulbs is the future.
Using just 10% of the energy to power them means that they are going to deliver really significant savings on your energy bills. This blog looks at the sort of savings you could potentially make from the relatively simple swap.
Thanks for posting this, quick question on GU10 vs MR16. If you’re fitting them from new, which would you recommend? Is one more efficient than the other?
Hi David, I would definitely go for the GU10 over the MR16 then you can do away with transformer issues. They both have the same efficiency though – so don’t worry about that point – a 5w GU10 will use the same amount of energy as a 5w MR16.
Re LED GU10 lamps. Has anyone else noticed that the life expectancy or these (expensive) lamps is far shorter that the Halagon ones? I put the date on the lamp base just to check. I have now returned to Halagon for my kitchen till such time as the colour rendering is better and the life is better
100% false. You must’ve had 1 bad ‘bulb’ (LED bulbs are called lamps, I think, and they contain many LEDs in each lamp). The LEDs in each lamp slowly fail and thus the light dims (30% failed LEDs is where they deemed to be dead, I think, or 70% ?).
Halogen bulbs claim to last 2000hrs (2 years average), but it’s more like 1000. Some GU10 LEDs claim 24,000hrs, but that’s an even bigger lie! However, the EU implemented a law in 2014 – LEDs now must last at least 6000hrs, so they last 3x longer than halogens, minimum (more like 6x longer or more)!
Either way, a 5w GU10 LED (dimmable) costs £4.50, and 50w halogen ones cost £1? But, you should find a saving in just the light cost, as you may need 3-6 halogens per 1 LED lifespan – then there’s the fact they’re only using 10% of the electricity.
Absolutely worst case: 1x 5w GU10 LED dimmable will cost you roughly £10 total costs for its 6000hr (6yr av.); You’ll need a minimum of 3x 50w halogens to last that long and they’ll cost you £50 total in that time.
You state : “The reason for this is that they need a minimum voltage to pass through them to operate “. I believe you mean “load” to pass through them. It is the load that causes the issue when it is not large enough to fully turn on the circuit.
Great article by the way. It is nice to see that someone out there is discussing this issue.
James above is so correct. GU10 is a great way to go. No transformer and the LED bulb will have its own driver. Win win.
Thanks David – point taken re: the load!!
Good article thanks, having a couple of halogen transformers die this week, I decided to move to LED, and i’ve just converted from MR16 to GU10 + 5W LEDs for £10 per fitting including LED bulb today, saved me some money and time being able to strip out the transformers. So thanks.
Thanks for your comment John. Funnily enough I was in my brothers home with weekend and they were have the exact same problem with their MR16 bulbs in the kitchen. He is now going to replace the MR16 bulbs with GU10s to get around the transformer issue and obviously moving to LED will also result in considerable energy savings for them!
I have a load of MR16…. so feeling the opposite of smug right now. The biggest driver of my unhappiness is cost per lumen, which seems to be better for GU10s as opposed to MR16s
What is involved in converting an MR16 fitting to a GU10? My MR16’s all have a box in line to the light which I assume is the converter if that makes it easier?
Hi Steve, unfortunately you need to change the fitting, so you would need to buy 1 new fitting + bulb (ideally LED) to replace each MR16 you have. This should cost about £15-£20 for each one you need to swap. Well worth it in our opinion especially if you are making the move from halogen to LED, so not only do you get substantial cost savings but also you don’t need to get the ladder out every couple of months to replace yet another blown bulb!
I have recently replaced my MR16 halogens with LEDs without knowing about the transformer issue. Only two of the six I have replaced so far are flickering. The lights are embedded in the ceiling of a kitchen extension built in around 2006. How do I tell if there is a single transformer for the system or indvidual ones for each light fitting. If it is a single transformer -where is it likely to be hidden?
Hi Janet, You need to take the bulb out and look in the fitting. Ideally turns the mains off and use a torch!
What no one seems to pick up on is the life of any bulb in hours is if the light is switched on constantly. Most damage occurs to the bulb in the sudden surge of power when the bulb is switched on. So I would say that all the hours the bulbs will last is not very accurate. Also there is no mention of a cost to fit new LED fittings, remove transformers etc. We aren’t all qualified electricians.
True, LED bulbs haven’t been around for 25 years so it’s impossible to say for certain. However, they certainly outlast the incandescents by a long long way. In terms of the fittings, you only need to change the MR16 fittings to GU10s. Every other fitting is fine for retro-fit bulbs.
Hi i have gu 10 led recess light at my 1st floor ceiling. I have a condensation problem at attic during winter because warm air from heater is slipping through my recess light to attic. Is it safe to cover and air seal light fixture from above at attic with proper heat proof box or metal box? Thanks
Are full voltage gu10 fittings cheaper to run than mr16 lamps on a transformer
I put a new light up with gu-10 bulbs on the existing dimmer switch and the switch makes a humming noise when on full power. Any ideas?
Hi Bob, so a lot of the older style dimmer switches either make the lights flicker or hum themselves. What we recommend is to buy LED compatible dimmer switches (which pretty much all new ones are).
Great article…. More questions/comments please – sorry!
(1) Many MR16’s & G4’s are sold as 3 on a transformer. If you have several MR16’s say 4 sets of 3 (12 total), could you simply connect all 12 new LED bulbs to 1 transformer (assuming that all 12 now draw the load required for 1 transformer)?
(2) You don’t always need to change the full fitting when swapping MR16 to GU10. My kitchen had the loose fly lead connections in the ceiling downlights. I rewired these to GU10’s mains and the old ceiling fitting still held the new GU10’s. You would not be able to do this on rigid fittings though!
(3) There’s total conflict on websites about what dimmer should be used for dimmable LED’s (leading, trailing, mains, 12V via driver etc). Please clarify.
(4) You can now get dimmable G4’s in 220VAC & 12VDC. This asks the question… is its best to swap the driver and use 12V LED’s or by-pass the original transformer and use 220V LED’s?
(5) I know that GU10 LED 220V on a dimmer they should be sold as dimmable, but if you use MR16 12V with a dimmable driver, are 12V LED bulbs already dimmable and OK for say 3-12V?
Another point worth noting… many spots produce ‘torch beams’ dark/light areas that are awful in kitchens. I’ve found that the smd LED versions give much better light spread.
Thanks
Adam
I am using GU10 led lights but i have a problem with this. all are dimmable lights .i am using these with a dimmer but my LED is flicking if the dimmer channel is switched off.My dimmer outs 40-50volts in off condition.Please find the solution.
how i can stop voltage in off condition.
Hi. I’m wanting to swop my MR16 fittings to GU10. Having just removed MR16’s and fitted GU10’s, they won’t come on. I presume from reading here that there’s a transformer in the ceiling that I need to remove? Can u just remove it and then wire them in?
Hi Cathy,
I really suggest getting an electrician to do this, however in principle that is correct – the GU10 does not need an external transformer, they are built into the bulbs themselves.
Whcih LED bulbs will work with MR16 Dimmable system? It has seven bulbs on our Kitchen systems, currently 50w 12v?
Thanks
You may get away with the Philips MasterSpot MR16 bulb. However, we would always recommend changing out your MR16 fittings to GU10 to avoid any problems.
Just what I was looking for. I’m not really electrically minded but I have 3 new mr16 colour changing bulbs and was wonder why they would flicker for a second and switch off. They are all 5watt rated so I wonder if you could send me a link to the transformer I would need from your shop. Thanks!
any thought whether changing from MR16 to GU10 one would need to consider new building regulation come in force in 2005, for me it is simple 2 wire which one need to change from one fitting to another
Hi, I replaced 5 MR16 transformers with GU10 fittings and LED bulbs. The first worked fine. I replaced the remainder which blew a bulb and tripped the fuse box. I removed the light bulb and tried again. It has now blown the switch and tripped the fuse box. There are 2 switches which control the 5 lights. One is a single switch unit (which appears to be fine). The other has a two switch unit. One for the 5 bulbs the other for another 12v dimable circuit which seems to be the problem. I’ve put out a request for an electrician but anyone any ideas? Thanks.
Hi there – I have six MR16, 12v halogens in my kitchen, four in my bathroom. I’m assuming that a transformer is installed to run each set of lights however I don’t know if they are new or old style transformers, I can’t access them without destroying the ceiling.. Is there a way around this? What would happen if I connected GU10 LED bulbs with a ‘MR16 male to GU10 female adapter’?
Hi, may I ask where you bought the LED”s. I have in the past purchased some cheap ones from eBay and they didn’t last long and started burning out (smelling from base) prob cheap components on the circuit board. Lesson learned, don’t buy cheap from eBay… So regarding your fault above one of the lamps could have short circuited and burned out the switch contact before the MCB. As mentioned if they are cheap ones I’d replace them all. If not get hold of the shop you bought them off and explain your issues, they may replace them free of charge.
Thank you for the explanation, I was thinking of buying some GU10 to MR16 adapters but after reading this I realized that they would not work unless I changed the voltage and that’s just too much work, thank you
Sticking to GU10
Thank you for Explanation ,i don’t know anything about lights and it’s specification, like IP 64 , IP 44 LIKE that Please give me a short explanation.
THANKS
The IP rating is the Index of Protection – and shows the protection rate of an electrical item from any external agents – namely dust and solid objects and water.
The first number gives the protection level against solid objects from 0-6 with 6 the best protection (i.e. no dust or anything would enter the device).
The second number gives the protection level against water ingress and goes from 0-8. Again the higher the number the better the protection so something with IP X 8 can be fully submerged.
Hi, quick question – so everything you have said makes perfect sense and has helped me a lot thanks. So if I currently have 4 x MR16 bulbs on one transformer, then I can replace that with 4 x 6W led bulbs and use 1 x 24 watt led driver.. is that right?
Hi Peter,
I would go slightly bigger with the LED driver – potentially a 30w – but yes that is the correct principle!
In my kitchen I have just replaced 20 halogen bulbs with MR16 LED’s. Each bulb has a separate Tamlite transformer attached. Once switched on and after a few seconds its like Saturday night at the disco. With the utility room there are 22 bulbs in all. Replacing each transformer will be too expensive. As each transformer is fed by 240 volts I’m thinking the best route is to throw away the transformers ant convert to GU10s. I’m assuming the conversion is straight forward? Your advice would be most welcome. Regards Bill
Hi Bill, replacing with GU10’s is 100% what we would suggest. The transformers make replacing MR16 a bit of a pain – especially given each bulb has its own one.
The conversion to GU10 is very simple – but we would always recommend getting a qualified electrician in to do this!
Can you please help me I used to have 6 Halogen Bulbs on one circuit then changed to 6 LEDS which worked fine but slowly one by one the transformers have packed in so I got some used ones and now the LEDS flicker. My original transformers were ET60T-5, and the used transformers I have flicker which are ET60T-2. Can you please suggest the best transformer I need to run 6 LEDS which are Osram 20w which are 12v5w
Hi
I never understood if the energy consumption of LEDs is measured including the transformator or not. They generate large amounts of heat and use energy.
I feel that the actual energy used is thus bigger than assumed. Am i wrong?
Tom
Hi
Really useful and concise info. I have just fitted some 7.5WWW 12v LEDs with no apparent problems or flickering. However, having read your blog I have checked and the trwnsormers are individual 20-60VA. Should I still replace them and if so about how much are I dividjal transformers I have 6 downlighters in the kitchen and about 15 upstairs that are still old bulbs?
Thanks
Andy
Hi Andy,
If you have bulbs that are working, then I would stick with what you have. If you don’t have flickering, it is unlikely to suddenly start down the line.
I have put up 4 new light fixtures with three halagens in each. They r hot and not bright. I have had them 5 months and over 6 have burned out. I a, a salon owner. Need bright white. Ordered some GU 10 15 w , but never came. What is the brightest bulb for the nest value and brightestness.
Base types are GU10 and GU5.3 respectively.
MR16 indicates spot light size.
It is a common misconception.
You are basically differentiating “Fruit and Oranges” instead of differentiating “Lemons and Oranges”
https://en.wikipedia.org/wiki/Bi-pin_connector
I have changed all my kitchen MR16 (12volt) bulbs for LED GU10 5 watt, warm white. Great result and able to use the existing fitting. Only needed to change the bulb connector leads and remove the individual transformers. WARNING, I tried a 12 volt LED and it caused the transformer to arc dramatically & blow up. To test that it was a one off, I tried another transformer with the same result! So I switched to GU10 (Lumlife) for huge energy saving and no more hot light fittings. Feb 2016.
Hi Ali, Yep – the move to GU10 from MR16 is a very wise one if you are going the LED route. I think it is worth swapping out any traditional bulbs that have a transformer with LED ones that don’t require them. There is just to much risk they won’t work correctly.
I converted all my light fittings in my old house to LED’s & noticed HUGE savings! I actually only did it to boost my home energy report..
I’m now currently changing all the bulbs in my ‘new’ home which is an old cottage; most of the light fittings need replacing also as they’re not earthed (!). One of the lights I’ve recently purchased needed a transformer to take the power down for my 2w bulb… I know, really low warm & bright ceiling light, but 2w that’s just phenomenal …. I’ll get to my point..
So my question is, should I have a new fuse fitted to my fuse board supplying the lighting in my home, ie 5amp, or am I totally confusing things? Also does a light fitting that requires a transformer still draw more power than using a standard LED light bulb with no transformer??… Please forgive me my ignorance!
Erm, you didn’t compare energy savings? The GU10 LEDs are going to be a straight swap for most people, but you don’t say if MR16 LEDs are worth converting to (unlikely?) or even if they’re more economical if you’re about to have new lighting fitted and can choose either type of fitting. Obviously any type of LED is better than halogen – at least 5x cheaper (worst case scenario for the LED), but most likely 10x more ecenomical. Either way, anyone one who’s just fitted 10 (or any number) halogen bulbs is far better off ordering 10 LED lights and swapping straight over and chucking the new halogens in the bin.
Hi, I have discovered some LED bulbs in our normal GU10 circuit in our rented house. They have blown however one still seems to be working. I am confused as to whether its okay to use LED downlights in the circuit straight out of the box as my understanding is that you need to convert your circuit how everthis one does seem to be working with a mix of halogen and LED. Any idea whats going on or whether someone has just tried to put LED’s in and got lucky that they work (at least they did for a bit but now most seem to have burnt out, like I said there is still on installed that seems to be working fine) Many thanks
Hi,
I’m currently doing a brand new extension at the moment, the gu10 downlighters I have gone for are fire rated, mains volatage. The Lights I have gone for is LED, which is the most logical way to go for these days, the power the light bulbs give out is 5w possibly 6watts the input on the manufactures website is saying 220v input which is the mains cable my question is do they require some kind of transformer or LED driver? Or just wire straight from the mains??
Many thanks Tufael
Hi, the GU10 LED bulbs will run straight off mains without a transformer or LED driver – it is only the 12v MR16 spotlights that require this.
Have you ever seen MR16 type bulbs in 220vAC ? I always thought the purpose of the different bases was to keep 12vDC bulbs from going into 220VAC, (or 120vAC here in the states), and going poof! and all the magic smoke comes out. I am seeing a disturbing trend of mr16 base bulbs being sold on eBay for 220VaC supply. Not a good thing if it is correct. I have checked several sellers of the same bulb, and they all are using what looks to be a manufacturer’s graphic image of the specs, not text.
They use multiple small COB LED’s with a distinct black background. Watch out!
Hi I have just bought an optimyst stove with four 12v 45w bulbs giving a glow and false smoke effect- obviously running through a transformer.. Please could you advise of costs for this lighting and smoke effect without using the 1 or 2Kilo watt heating.
What is the power consumption of a GU5.3 50watt bulb at 12v please? Is it the same as a GU10 50watt bulb?
Mr16 is the bulb shape, gu10 describes the two posts that are the connection to power. For instance mr16 gu 5.3 is a little flood with two pointed push in pins for connection, and either base type can be 12v or 120v.
I ave recently moved into a house which has a lot of MR16 downlighters, currently all 50w halogen. I would like to switch to LEDs, and there is lots of publicity suggesting that this is easy and will save lots of energy and cost. I bought 3 Philips 8.2w LED lamps to try, but they flicker badly. I have inspected a few of the more accessible fittings, and they seem to be mostly fed from individual magnetic transformers (MAE E-60), with one or two ‘electronic transformers’ (DAIS DA E-60 and a unit branded ‘Click’, the model number of which I couldn’t easily see. A Google search brought me to your article, which says ‘Now the older magnetic transformers will work perfectly with LED MR16s’, but this is not the case, they all flicker badly. Philips customer service were not surprised at this, but suggested that the DAIS unit should work, but it and the Click unit also flicker. Am I missing something, or am I really faced with trying to replace all the units above the ceilings ? If so, with what ? Thanks
Hi, I have 5W 220V MR16 LEDs, They’re GU5.3 base. On my place the main power is 220V AC. I’m going to use them to replace the old halogen lamps. Should the LEDs need drivers or transformers to run or not?
Hi there. Wonder if you could advise. I have a couple of mr16 bulbs in my downstairs shower room. When I turn on the light switch this action also activates the extractor fan in the room. What I want to ask is – what is the likelihood of my having one of the older “wire-wound” type of transformers in this shower room as opposed to one of the newer low-voltage electronic ones. My shower room was installed 12 years ago and I am wondering if the newer electronic transformers were commonly in use back then, or would it be much more likely that I would have the older “wire-wound” type. Your opinion would be appreciated.
MR16 means multifaceted reflector with a diameter of 16/8 inches. GU10 is a 2 pin bayonet style mount that is commonly used on MR16 bulbs designed to run at 120V/230V AC.
If you’re going to write stuff and publish it as factual information on the internet for other people to read, perhaps you might consider spending 5 or 10 minutes researching the subject matter before putting pen to paper (or index finger to keyboard). You could start by Goolging GU5.3.
Hi, i have 6 MR16 Spotlights in my kitchen all requiring there own transformers,
I want to move away from MR16’s and move to GU10 LED spotlights.
Why would the electrician who built my ground floor flat opt for MR16’s over GU10’s?
how simply is it to transfer over?
We have GU10+C 120V 35W bulb in our range hood vent.
Manufacturer Instructions call for replacement bulbs to be MR16 (GU-10) s5W halogen.
1. Do I buy MR16 or GU-10 ?
2. What does “C” means?
3. What to buy as LED replacement for the halogen?
Tad[pole
You are totally off-base. Gu 10 refers to the pin type and MR 16 is a Multi-Faceted reflector. MR 16’s come in both GU 10 and GU 3.5 base types
Not entirely accurate as in greece and eastern europe you can get mr16 fitting spots that use 230v and can be replaced with mr16 230v leds.
Unavailble in the uk (for I think safety reasons) as the pins on mr16 could be exposed whilst live and would be deemed dangerous.
Even I learn as I read, Mr16 is the bulb type but gu3.5 is the 2 pin base,