LED flicker

[hard-work]

I looked at the LED lamps. 5w, 500ma and 12v ac/dc. There are three lamps.

 

[Diy-mañana]

Just had 12v halogens in our bathrooms changed to LEDs.we are new to this house and the bathroom lights flickered and made buzzing sounds.
Straight forward job,left it to a qualified electrician,he provided the 14 downlighters cheaper than I could. Electrician pointed out after removing the halogens that some of the fittings had mismatched components transformer not suitable for bulbs,melting transformers,brittle wiring above showers and something to do with zones.T he fire hazard was a shock to me.
So all done now,very happy with the new lights electric test certificate issued,. This is a job I was going to do but clearly out of my scope.

 

[hard-work]

In the case I highlighted, the topic of this thread. All is needed to is replace the transformer to one with the correct watts range; one that handle 15w. But one poster here says only a dedicated LED transformer will do and others any will as long as it is within the watts range. The LED lamps at 5w, 500ma and 12v ac/dc, seem to indicate that a specialist LED transformer is not needed.

 

[winston1]

In the case I highlighted, the topic of this thread. All is needed to is replace the transformer to one with the correct watts range; one that handle 15w. But one poster here says only a dedicated LED transformer will do and others any will as long as it is within the watts range. The LED lamps at 5w, 500ma and 12v ac/dc, seem to indicate that a specialist LED transformer is not needed.

FOR THE NINTH TIME, you need a proper LED power supply. They are cheap enough so why get the wrong thing?. The lamps are designed for 50/60 Hz AC not 40kHz which will cause them to overheat and shorten their life.

http://www.ebay.co.uk/itm/High-Qual...4057eb4&pid=100005&rk=1&rkt=6&sd=230689466731

 

[333rocky333]

Winston,
Why link to a cheap CHINESE crap item.
It was you that claimed they are NOT transformers and not to trust sellers that call them that and then you post a link to one.
What a hypocrite.

TO THE OP DO NOT EVEN CONSIDER THAT UNIT.

Buy a 12 volt constant voltage transformer from screwfix or Band Q with a minimum load if any, lower than the total of the 3 lamps you have.
You could buy a lower minimum wattage halogen transformer for the same price and find a slight chance it is still unstable.
Therefore if your going to pay then get the led one.

 

[333rocky333]

In the case I highlighted, the topic of this thread. All is needed to is replace the transformer to one with the correct watts range; one that handle 15w. But one poster here says only a dedicated LED transformer will do and others any will as long as it is within the watts range. The LED lamps at 5w, 500ma and 12v ac/dc, seem to indicate that a specialist LED transformer is not needed.

The situation is there are so many makes of Transformers and so many makes of Led lamps.
Most are only tested with certain combinations and usually with transformers currently sold, which are made with consideration for running Led lamps.
Older units like you have may or may not work even if minimum load is met as they were not built with led in mind.
A new set up you would choose a matching combo that has been tested by the suppliers.
Earlier I posted a link to a chart where a maker has done this, that shows with halogen all fine, but with some transformers the Led lamps were unstable even above the minimum rated transformer load, yet others were stable even when underrated, so it really is hit and miss with untested combos.
Did you state the make of the Led lamps earlier.
At the end of the day you know your under the minimum load.
Option 1 get a lower load halogen transformer
Option 2 get a lower load Led transformer

Option 1 is hit and miss
Option 2 is more likely to resolve the issue

 

[bernardgreen]

The situation is there are so many makes of Transformers and so many makes of Led lamps.

Which means that the interface voltage between power source and the lamp needs to be defined and then items chosen to match it.

There is no such thing as an LED power supply when considering domestic lighting.
There is a power supply that supplies constant voltage or ( constant effective voltage ) for the lamp.

effective 12 volts may be produced from 24 volts chopped ON and OFF at 50/50, it may or may not be smoothed

In the case of a lamp using LED element(s) there will be inside the lamp an LED driver which controls the current driven through the LED element(s).
In the case of filament lamps the voltage from the power supply is connected directly to the ends of the filaments ( maybe an internal fuse in fitted in one lead )
The filament or the LED driver must match the power supply.

In the following the value of 12 maybe replaced by other supply voltages such as 11.6 for optimum halogen lamp operation

The most common supply sources are

1). 230 volts AC ( direct mains )

2). 12 volts AC pure sine wave ( from a wound magnetic conventional transformer ) Will have no minimum load rating

3). 12 volts AC pseudo sine wave ( from an electronic convertor ) Most will have a minimum load rating

4). 12 volts DC smooth DC ( from a battery or from an electronic power supply ) Has no minimum load rating

5). 12 volts DC (eff) ( a rapid sequence of different voltages which average out to be 12 volts ) Will have a minimumm load rating


Almost any 230 volt lamps, both LED and filament, will work on type 1)

Almost all 12 volt filament lamps will work on types 2), 3), and 4)

12 volt filament lamps will work on type 5) but low wattage filament lamps may show some variation of light intensity if the rate of voltage sequencing is slow. High wattage filament lamps with thicker filaments and thus more thermal mass will smooth out the variations in voltage. There is risk that the peak voltages higher than 12 volt may damage the filaments

LED lamps designed to work on 12 volts AC will work on type 2)

LED lamps designed to work on 12 volts AC may or may not work on type 3) depending on the way the pseudo AC sine wave is generating in the power supply

LED lamps designed to work on 12 volts AC may work on type 4) some are dependent on the supply being AC

LED lamps designed to work on 12 volts DC will work on type 4)

LED lamps designed to work on 12 volts DC will work on type 5) but :-

a) smooth operation of the LED current driver may be affected by the variations in the 12 volt (eff) supply
b) may be damaged by the the peak voltages higher than 12 volt that will be in the 12 volt (eff) supply

 

[333rocky333]

All true Bernard, but I believe in advance of the phasing out of mr16 12 volt halogens, leading makers have had to do there own research.
Company's like Megaman, osram etc, list compatibility on there websites, ignoring that as most find out is where the problems occur.
Despite Winston's ramblings some Mr16 12 volt push in Led lamps, DO actually work with Electronic Transformers originally installed for halogen lamps, and there tests have proved this and I am certain there tests are more in depth than Winston's mock up test.

Spirit pub group, prior to there take over supplied Led 12volt lamps to nearly all there outlets to replace the halogen lamps, at a guess i would say the majority would have had single Electronic Transformers for each lamp and to my knowledge there was few issues.
This forum only hears of the Failed efforts, in reality there is likely more unheard successful relamps, to allow the lamps to be sold as a true retrofit replacement lamp

 

[333rocky333]

. Picture can be made available

When your ready

 

[bernardgreen]

but I believe in advance of the phasing out of mr16 12 volt halogens, leading makers have had to do there own research.

And the greedy un-ethical makers who have no regard for safety have done their creative worst to take advantage of the ignorant public and increase their ill gotten profits.

RANT OVER.......

 

[rules&rulers]

edit,incorrect forum.

 

[EFLImpudence]

He posted just before mid-day.

Probably gone out for the afternoon; to football or something worthwhile.

 

[hard-work]

This looks like it would do. I saw nothing at Screwfix that looked suitable.
https://www.tlc-direct.co.uk/Produc...1LBE3DZCUY7C_fscV51XH7Hh0uEM6aA8aAvNvEALw_wcB

 

[winston1]

This looks like it would do. I saw nothing at Screwfix that looked suitable.
https://www.tlc-direct.co.uk/Produc...1LBE3DZCUY7C_fscV51XH7Hh0uEM6aA8aAvNvEALw_wcB

FOR THE TENTH TIME you need a proper LED power supply not an SMPS that runs at tens of kilohertz. Maybe some LEDs can operate off a SMPS but you have NO IDEA if your neighbours are of this type. An LED power supply is not expensive.

Here is one you did not find at Screwfix

http://www.screwfix.com/p/halolite-led-constant-voltage-driver-1-16w/85503

 

[winston1]

Winston,
Why link to a cheap CHINESE crap item.
It was you that claimed they are NOT transformers and not to trust sellers that call them that and then you post a link to one.
What a hypocrite.

It's made in China. It's low cost. What justification do you have for claiming it is crap?

I-phones are made in China. Are they crap?

Indeed they are not transformers, but all through this thread members have been wrongly referring to SMPS as transformers thus causing confusion, but the mods seem to not want us to discuss it.