How many lumens and what beam angle for LED

xyz123

Hi

Looking to replace the gu10 halogen in kitchen. These are ceiling mounted fitting with three bulbs. Existing ones are 50w.

With all the variety out there what is the realistic lumens I should look for when choosing replacement LED? Also what about beam angle? Obviously wider the better in general so as to avoid darker spots in kitchen. Any advice?

Ta

jamesd

A 50w equivalent would be about 900-950 lumens. LED and CF lifetimes are measured in hours before light output drops to a percentage of its initial value, perhaps 70%. You might want to over-specify to allow for this.

Personally, I've replaced non-halogen ES 40W spotlight bulbs with CF and now LEDs in greater outputs, most recently using a 100W equivalent LED in one spot, 75W in another. These are oversize for the fitting and some might object to that. I don't, I want the higher light outputs.

You might also consider the colour temperature. Cool or daylight temperatures would probably be better for a kitchen than warm white.

jimbo_the_jetset

Just bought some MR16 led's with a single central COB, 380 lumens, 90 degree beam angle, in both warm white (3000k) and natural white (4000k).

First impressions are that they are not quite as bright as the previous 50W halogens. Perhaps due to the lumen count and also the wide beam angle. Prefer the natural white as the warm white appears too artificial.

Just ordered some multiple SMD's which have a high lumen output of 460lm and a narrower beam angle of 60 degrees. Hopefully, they will be a bit brighter.

xyz123

Thanks. Can you tell me where did u get the leds from?

Ta

jimbo_the_jetset

Fitted the higher lumen SMD's and I am definitely much happier with the overall light out. Since this is my first LED spotlight experience I would suggest to replace 50W halogens you need >400-450 lumens.

Got my (MR16's) from LED Save based in Hull, which is not too far from me. Got some decent advice on the phone from them and they offer a 5 year warranty (think you need to fill out a form). They also confirmed I could order a number of different ones to try out and then return them for a full refund, some places charge a re-stocking fee so be careful. Oh, and they had a VAT free (20%) offer on when I ordered.

almillar

You want roughly 500 lumens to replace 50W. I've got a previous version of these which are very close:
http://well-lit.co.uk/product/5w-led-spot/

largeloins

This is a great thread!
Does anyone know what the payback or running cost calculation is for 50W 12v MR16 halogens vs equivalent LED's? as the builder of my house installed them everywhere when he built it - I've got 55 to replace!
I've also heard that I'll have to change my 20-60W/VA transformers to "LED transformers" also is this true?
thanks
Ian

jimbo_the_jetset

Fitted 10 MR16's in my kitchen and didn't need to change a single transformer.

locky123

largeloins wrote: »

This is a great thread!
Does anyone know what the payback or running cost calculation is for 50W 12v MR16 halogens vs equivalent LED's? as the builder of my house installed them everywhere when he built it - I've got 55 to replace!
I've also heard that I'll have to change my 20-60W/VA transformers to "LED transformers" also is this true?
thanks
Ian

Remove transformers and fit GU10 flying leads, you'll find more choice with LED GU10s and remove risk of MR16 LEDs not working with existing transformer. Some have problems with latter and some dont.

Have a read of this ... http://well-lit.co.uk/why-led/

Make sure you have up to 3 year warranty with LED supplier, failure rates can be high depending on quality of LEDs.

JohnB47

jamesd wrote: »

A 50w equivalent would be about 900-950 lumens. LED and CF lifetimes are measured in hours before light output drops to a percentage of its initial value, perhaps 70%. You might want to over-specify to allow for this.

Personally, I've replaced non-halogen ES 40W spotlight bulbs with CF and now LEDs in greater outputs, most recently using a 100W equivalent LED in one spot, 75W in another. These are oversize for the fitting and some might object to that. I don't, I want the higher light outputs.

You might also consider the colour temperature. Cool or daylight temperatures would probably be better for a kitchen than warm white.

50w equivalent would be 900-950 lumen? Not for a gu10 spot, methinks. More like 480 lumen.

flashg67

locky123 wrote: »

Remove transformers and fit GU10 flying leads, you'll find more choice with LED GU10s and remove risk of MR16 LEDs not working with existing transformer. Some have problems with latter and some dont.

Have a read of this ... http://well-lit.co.uk/why-led/

Make sure you have up to 3 year warranty with LED supplier, failure rates can be high depending on quality of LEDs.

You will likely have to also replace, or ensure you add an earth if you change to 240 volts, but agree there is much more choice