Changing to LED bulbs - flicker

[Caz6]

Changed the kitchen downlights from 50W to GU10 LEDs, very impressed by the results, so decided to buy some Lumilife LED 5W MR16 bulbs for the bathroom. but these flicker when switched on. Do some research, find that its related to the transformer. Get in the attic, find that each downlight has its own transformer which looks like this:

The transformer details are:
Tamlite EU-2060

So the stupid novice questions are:
- whats causing the flicker with the LED bulbs.?
- Do I need to replace each transformer, and with what?
- is it easier (and legal) to replace with 240V downlights (in bathroom, attic above)
- will it be cheaper just to continue with the 50W bulbs and forget about LEDs

Thanks.

 

[flameport]

Get rid of the transformers, change the lampholders to GU10, fit GU10 LEDs.
http://www.toolstation.com/shop/p34667

 

[ericmark]

I think the Tamlite EU-2060 is for 20 to 60 watt or VA and your lamp is 5W so need to power at least 4 lamps from each "transformer" I would select 5 so one can fail without a problem.

The lighting industry seems to have a problem with the English language everyone else would call a collection of electronic bits and transformer to give a regulated 12 volt output a power supply but the lighting trade calls it the electronic transformer.

 

[ericmark]

Get rid of the transformers, change the lampholders to GU10, fit GU10 LEDs.
http://www.toolstation.com/shop/p34667[/QUOTE]
I would agree. The main reason for the regulated power supply and 12 volt was to have thick elements and a exact temperature. The quartz envelope is so hot the tungsten will not deposit on the quartz but instead back on the element over time the thickness will vary and in the end the element will rupture but using a regulated 12 volt rather than 230 extended the filament life.

With LED this is no longer required. The LED is a current device and will stay at a set voltage normally around 1.2 - 2 volt and different methods are used to limit the current.

This could be a driver or a simple resistor and with 230 volt versions the simple resistor would produce too much heat so in the main a switched mode power supply is built into each bulb. This often gives a voltage range of 150 - 250 volt and means a really good lumen per watt output.

With 12 volt versions you really have no idea of the method used. I could also be a switched mode system or it could be a simple resistor. With the latter a 2 volt LED needing 0.42A could be 0.84 watt at 12 volt with a switched mode power supply of 5W with a simple resistor.

You have no idea as to method used. Using 5 LED's in series so 10 volt they may get a reasonable lumen per watt but even then you have no idea if using full wave or half wave rectification so may not work with a switched mode power supply.

Again the lighting industry seem to have an English problem and they call voltage regulated DC power supplies drivers where really a driver is a current device and would need to be matched to the load.

So all in all simple method is to use GU10 bulbs although even that is a problem. GU10 refers to the bayonet fitting and MR16 refers to the size so a GU10 could be a MR16 it's really a problem we know DOS = Device operating system and CLI = Command line Interface and they could refer to the same thing but Windows 8 is still a device operating system even though we would not normally refer to is as DOS.

 

[jeds]

I can recommend these.

http://www.ledhut.co.uk/spot-lights...t-led-ceiling-light-transformer-included.html

Just fitted 10 to a dimmer (warm white) and they are really very good.

 

[ericmark]

When I fit lights I want to be able to go out and buy replacement bulbs from local shops and not be forced to use internet and be without for a week while replacements arrive.

So I would use a STANDARD GU10 fitting which can than be maintained without any hassle.

To reduce the current with a GU10 bulb normally a switched mode unit is built into the bulb making them efficient but also can stop them being dimmed. Using a simple resistor would allow dimming and be cheap to manufacturer but not practical to drop from 230 volt to 2 volt needed for a LED. But from 12 volt to 2 volt or with 3 LED's in a cluster 6 volt using a simple resistor is an option.

Look at most 230 volt GU10 bulbs and the voltage is 150 - 250 volt clearly they use switch mode chips inside the lamp. Look at MR16 12 volt lamps and the voltage simply stated as 12 volt only way is to compare lumen to watts to see how efficient the current reducing device is.

The lack of any information as to lumen output makes me think it is likely very poor for the power used. With out the info I would not touch them could be great but also could be cheap rubbish there is no information to identify which. And since it says can use any dimmer switch likely cheap rubbish.

 

[ban-all-sheds]

When I fit lights I want to be able to go out and buy replacement bulbs from local shops and not be forced to use internet and be without for a week while replacements arrive.

I want to be able to replace the lamps from spares I have in the house, and not be without until I can get out to the shops.

Keep spares in stock and replenish when used.

 

[Taylortwocities]

I expect to fit integrated LED fittings that have no replaceable parts and have a five year warranty.