LED bulb 50 Hz what why use driver?

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Decided to replace my four failed LED GU 5.3 lamps, in the bathroom. Lidi were doing pairs of 3W lamps for £6 so forked out £12 to renew them all. And on the outside packaging it states 50 Hz so they should do the job nicely.

Once opened it had a flyer inside which said

“GB
1. Connecting the lamp to electronic transformers that are not designed for LED applications can lead to flickering or damage the lamp.
2. Be sure to consider an eventually required base load on the secondary side when using an electronic transformer.
3. LED lamps should function seamlessly with conventional (magnetic and/or wound) transformers.”


This raises some point.
  1. Why does it say 50Hz on the outer readable packaging then say what to do with an electronic transformer which is unlikely to be 50 Hz.
  2. Why do I see so often on these pages about using a “Driver” when be it current or voltage regulated near all drivers as DC, clearly at 50 Hz these lamps are AC.
They worked A1, simply replaced the 0.58 Watt from Pound shop with 3W lamps all connected to my 200 VA, toroidal core transformer no alterations made in any way.
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The picture all part of instructions which came with lamps.
 

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Just another case of manufacturers or their marketing people not knowing what they are talking about. They don't even know that there is no such thing as an "electronic transformer" as transformers by definition don't change the frequency.
 
So what would you call a device which transforms the frequancy? Would it not by the English definition be a transformer? OK I know we would normally call it a converter, or a vibrator, or inverter the latter once we start using electronics. But if a device transforms the voltage, current, or frequancy it must be a transformer, where the problem arrises is with the isolation transformer, this does not transform anything so really not a transformer.

However my point is the units are clearly AC, other wise not 50 Hz, and also it seems they can be used with diffrence frequancies as well if as the paper included they can be used with "electronic transformers", but I have told so many people that 12 volt LED lamps need a DC supply, be it called simply a power supply or driver does not really matter.

I got it wrong, they are designed for AC supplies not DC. I am holding up my hands and admitting I got it wrong.
 
A frequency converter "transforms" frequency. One definition of a transformer especially says it does not change frequency. Isolation transformers never seem to fit the definitions.

I suspect those Lidl LEDs have bridge rectifiers in them and that they will work on DC. Perhaps you could try one. If they got it wrong about 50Hz chances are they got that wrong as well.
 
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A frequency converter "transforms" frequency.
What's another word for converter?
What's another word for transformer?

One definition of a transformer especially says it does not change frequency.
Only one? Why does it say that?

Isolation transformers never seem to fit the definitions.
Perhaps the definition is wrong. Written by the marketing people at the time. Now, there's a thing.


Why does your hallowed definition of transformer go into the method of construction rather than just stick to what it does?
 
You will note from definitions 2 and 3 that some cars, in fact, are NOT road vehicles nor powered by internal combustion engines

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Getting the thread back on topic?? Give over, it'll never catch on!

Nozzle
 
These aren't £6 a pop, but I've been really happy with these:
https://www.scolmore.com/_pdfs/inceptor_micro.pdf

I don't know what LED is inside, at 55Lm/w they aren't the best, but certainly bright enough for domestic use. I have 4 in the family bathroom and its insanely bright.
These are low voltage, the ones I am talking about are extra low voltage, also £6 a pair so rather cheap. What I am saying I have jumped to the conclusion that the 12 volt LED lamps were really DC, but clearly since not polerised must have a rectifier in them so would work on AC. However with AC you can have spikes which could damage the LED so using on AC could be a problem, specially if from a switch mode power supply where it may not be a true sine wave.

However I am clearly wrong, they are not only designed for AC but it would seem designed for 50 Hz. Clearly with a 50 Hz supply it will not be a switched mode power supply however the insert seems to show they will work with a switched mode power supply as long as the minium load is maintained.

I am not happy using lamps which if one should fail it will underload the power supply, be it tunsten or LED to my mind it should work with just one lamp. However LED do not fail as often and even when they do fail it seems they do not always fail completly, I have had the orignals drop from 9 LED's to 6 and then 3 within the lamp, so likely the current used also dropped. Very diffrent to a tunsten where the lamp worked or it did not work, it never 2/3rds worked or 1/3rd worked.

The new lamps have 12 chips I would guess in 4 banks of 3 so again likely it can part fail.
 
Ditto. I have installed heaps of those, some in my house too and have no complaints.
They are what is called DoB fittings (Driver on board). Although our colleague, Wingey1, has asserted that driver is also the wrong term:rolleyes:
I have always considered a driver as a current controlling device, but it seems anything used to supply a LED is called a driver, be it voltage or current controlled, although they do seem to be DC not seen an AC power supply called a driver yet. I always considered them as the device which pushed the correct current through the LED, in the same way as a screw driver pushed the correct torque through a screw. But the meaning was not really hammered home.
 
I don't like to pick, Eric. But the Inceptor LEDs themselves are ELV (36v). Supply to the integrated driver itself is 230v.
The LED elements ( there appears to be 10 or 11 of them ) are almost certainly connected in series and the driver is pushing 150 mA through that series change of LED elements. As a "white" LED has a forward voltage drop somewhere between 3 and 4 volts a series chain of 10 LED elements would need a driver capable of coping with between 30 and 40 volts on its output when pushing 150mA into the chain.

The voltage on the output is NOT set by the driver but is determined by the sum of the voltage drops across the LED elements.
 
I don't like to pick, Eric. But the Inceptor LEDs themselves are ELV (36v). Supply to the integrated driver itself is 230v.
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A lamp as a unit which gives out light, a LED is a light emitting diode which are often included in a lamp. I always considered the lamp as the whole thing, after I ordered a head lamp and got everything bar the bulb, it was explained that orignally the cart would have a spigot to which the lamp was fitted, same on the wall in a house, inside the lamp we had a wick, mantal or a bulb.

With the LED lamp we again have a device with a load of components inside. Hence why I call it a LED lamp not a LED, yes technically the fitting is also part of the lamp, but one has to call a limit some where.

So I don't like to pick!!! but the Inceptor LEDs themselves are 3 volt like all white LED's but the Inceptor LED lamps themselves are 230 volt.
 
but the Inceptor LEDs themselves are 3 volt

It becomes necessary to use the description "LED element" when trying to explain things.

I notice the data sheet refers to the SMT LED and its benefits :-

SMD LED’s require lower current and create less heat than standard LEDs, perfect when space is at a premium.

The SMT ( Surface Mounted Technology ) LED is a LED element whose terminals are tabs that are soldered or spot welded to the metal conductors of the PCB rather than having wire leads that solder into holes in the PCB. The SMT LED can run cooler when the PCB is thermally bonded onto a heat sink.

The current to brightness ratio depends on the chemistry of the LED element.. The method of mounting the LED element to the PCB has little if any effect on the ratio.
 

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