LED Bulb Thread

fornowagain · 3 Feb 2014 at 14:22

Cheetah Designs said:
I am having some issues with some flickering LED lights and some that come on for a few seconds and then turn off.

Somebody pointed me to this: http://www.lightbulbs-direct.com/article/replacing-12v-halogen-mr16s-with-leds/

Can anyone actually explain what the maths for working out whether an LED will work in my transformer or not because it doesn't make a lot of sense to me.

Example 1 - I assume that is 5x12 = 60VA....but example 2 I dont have a clue.

Couple of things, you're under-loading the transformer and they don't output clean 12v. It's not a complicated circuit for Halgons, which are just big resistive loads with a high initial transient current. The LED's may pull below the minimum working load for the transformer and the output may be not a clean regulated 12v. It best to use transformers/driver designed for the application, and you might find running the old tx out of spec causes local rf interference.

Cheetah Designs · 3 Feb 2014 at 14:48

Nightglow said:
Got a link for that quote.

Its the link in the original post I made.

fornowagain said:
It best to use transformers/driver designed for the application, and you might find running the old tx out of spec causes local rf interference.

The problem I have is that I am renting so can't mess with the electrics and there are lots of these 50W downlights that I want to replace with low Watt versions.

Burned_Alive · 3 Feb 2014 at 15:28

Can anyone recommend a G9 replacement LED bulb? Probably around 25w equivalent.

fornowagain · 3 Feb 2014 at 16:48

Cheetah Designs said:
The problem I have is that I am renting so can't mess with the electrics and there are lots of these 50W downlights that I want to replace with low Watt versions.

Ah, ok have a look at 'retrofit' lamps. E.g. Philips CorePro

Cheetah Designs · 3 Feb 2014 at 17:31

fornowagain said:
Ah, ok have a look at 'retrofit' lamps. E.g. Philips CorePro

How do they differ? (Ie why would they work and others not?)

Here are the details of the transformers I have:

Transformer 1:
https://drive.google.com/file/d/0B4Mz-WnXHUIINWFDUkpROEhKczQ/edit?usp=sharing
https://drive.google.com/file/d/0B4Mz-WnXHUIIY3FnSGUzend6SGM/edit?usp=sharing

Transformer 2:
https://drive.google.com/file/d/0B4Mz-WnXHUIIWC1IU19HVzhBM2s/edit?usp=sharing

Cheetah Designs · 3 Feb 2014 at 17:31

Double post

fornowagain · 3 Feb 2014 at 18:17

Cheetah Designs said:
How do they differ? (Ie why would they work and others not?)

Retrofit units have inbuilt driver circuits to make them broadly compatible with older electronic transformers. No guarantees though, buy one and see if it works.

Cheetah Designs · 3 Feb 2014 at 20:11

Ah right - so is there any way to tell whether these retrofit ones work with my transformers? Are the Philips CorePro ones the only ones that can work or are there other "retrofit" ones that can work?

fornowagain · 3 Feb 2014 at 21:28

No not really, too many variations. You stand a good chance with the Philips. There are others I'm sure, you'll have to look for ones specifically designed for older fittings with enhanced driver circuits. There are other ways to fudge it, connect a few lamps together to increase load etc. But if you can't change the wiring you'll have to try one and see.

ecksmen · 3 Feb 2014 at 22:24

New build house has led bulbs, far too bright and white in the kitchen. Swapped with osram leds from Morrison at £8 per bulb, slightly dimmer but a warmer glow much happier now.

Lisapete · 5 Feb 2014 at 09:48

Got a new build and in the kitchen has 6 spot lights.

I've no idea on the unit etc etc but know the bulbs are GU5 and are a mix of 35w & 55w

They keep popping etc etc. I've no idea what to do to replace them ie just the bulb or the overall unit (not sure how easy this will be as only have round holes.

Being a kitchen something bright is important.

Has anyone any advice at all please

Nightglow · 5 Feb 2014 at 10:11

Not particularly fond of MR16 / GU5.3 LED lights & transformers.

I would replace the with a GU10 fittings, you don't say whether they are track or recessed light.

See my earlier post #814 further up the page for recommended GU10 downlighters.

Lisapete · 5 Feb 2014 at 16:32

I don't really understand all the light stuff. I will need to replace the lights full stop

I need to get something in them asap so just bought there http://www.ebay.co.uk/itm/251431316480?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1497.l2649

Caged · 6 Feb 2014 at 16:30

So you come in asking for advice, don't read it, and buy the first thing you can see on eBay? Which look exactly the same as the ones in this video and are therefore garbage

http://www.youtube.com/watch?v=B3i6OnCNacM

v0n · 6 Feb 2014 at 16:42

In recent months more and more far eastern LED manufacturers started cutting corners on colour temperature compliancy. You used to be able buy LED bulbs with cold,day,warm white hue with LEDs specifications actually emitting light in correct kelvin range. The last three batches I got from internet, even the new gunmetal heat spreader designs pimped all over the internet, the SMD LEDs were one and the same spec, but the manufacturer used different colour filter behind LED, inside reflector. The result is very yellow light reflection close to the bulb but pale light in centre of the main beam farther away. Obviously that's of no use if you need particular colour temperature and looks weird when mounted in spotlights, or used as a background light on walls.

Lisapete · 7 Feb 2014 at 20:05

Caged said:
So you come in asking for advice, don't read it, and buy the first thing you can see on eBay? Which look exactly the same as the ones in this video and are therefore garbage

http://www.youtube.com/watch?v=B3i6OnCNacM

Read my post. I don't have the option to rip out the current setup, it's too much of a mess. I needed something asap. They are being collected tomorrow

LED hut didn't have stock

Mark A · 8 Feb 2014 at 12:46

Caged said:
So you come in asking for advice, don't read it, and buy the first thing you can see on eBay? Which look exactly the same as the ones in this video and are therefore garbage

http://www.youtube.com/watch?v=B3i6OnCNacM

Interesting video. The crappy ebay one he took apart looked exactly like the ones a lot of us were recommended at the beginning of this thread that failed after a few weeks.

He's only done one video on led lights, would be great to see a few brands taken apart.

Caged · 8 Feb 2014 at 13:21

Just a quick trip report, I bought some of these LED downlights in warm white http://www.tlc-direct.co.uk/Main_In...ownlights_Index/LEDlite_Downlights/index.html and they arrived today.

The quality isn't quite at the same level as the Photonstar units I've been using before, but they cost about a quarter of what those units cost. Lots of really nice features and accessories available for them too - different beam angles you can change with lenses, baffles, bezels etc.

For the money they are excellent quality, they appear really well built, light up instantly and have a decent weight to them. I can't find fault with the light quality either.

These aren't on a dimmer so I can't report on the quality of the dimming.

Lisapete · 8 Feb 2014 at 17:56

They arrived today and quality is shocking. I only tested one and doesn't work, i get a flash that's it. Sending them back.

2 strip lights are doing the job right now. Until the kitchen is rebuilt they will stay as is

DannyW · 8 Feb 2014 at 20:55

Is it just me or does anyone else think LED gu10/mr16 are mostly garbage, I just don't think the technology is there yet, Ive had 2 sets of GU10 and 1 set of MR16 (my house is random) some were from ebay some from a proper shop branded makes that felt quality and every time had at least 1 faulty bulb

Bet ive spent £70 now and still not happy, from my experimenting ive found MR16 LED is a waste of time, best off to ditch the transformer and go back to GU10

Anyone else agree with me or have I just been very un-lucky ??