Any benefits to GU10 LED over GU5.3 MR16 LED

[Hayabslee]

As per a previous post, I've been changing existing GU5.3 MR16 halogen bulbs to LEDs (leaving the existing transformer in and not using any LED driver as they appear to be working).

A few people have said, I should simply do away with them, get rid of the transformers and simply convert each light to GU10 mains powered.

If the existing GU5.3 LEDs are currently working, is there any benefit in me taking the time to convert them?

 

[ericmark]

Likely no, the main problems with 12 volt lighting is.
1) The power supply has a limited band of operation, so it may fail if under loaded or over loaded.
2) The frequency may be such that adding a diode causes it to transmit.
3) There is nothing on the G5.3 system to stop you using unsuitable lights.
The GU10 and GZ10 and the L1 version of GU10 have outer tapers and centre pins so all lamps will fit into a GZ10 and only LED lamps in a GU10 L1. So it is a much safer system as you can,t fit lights which are too hot. Also no problems getting correct power supply.

With the G5.3 LED lamps you can get AC or DC, the AC version is often marked 50 Hz, and has a very narrow voltage range, the DC version is often 10 - 30 volt but needs a smooth DC supply and they are designed to be supplied from a battery, and need a smooth supply, some DC power supplies are switch mode and send pulses which average 12 volt but would upset the switch mode driver already built into the lamp.

I must admit I am tempted to try a 12 volt G5.3 in the caravan from local store, they are far cheaper than proper ones, but I think I will send for proper DC LED MR16 lamps.

I do use G5.3 MR16 LED lamps in the bathroom which seem to work well, but I know they are powered from a toroidal lighting transformer so I know they are OK.

 

[333rocky333]

Have you thought about replacing with something like these, there usually about 85 mm diameter


https://www.ledkia.com/uk/buy-basic...MI8rupk4iq3wIVArTtCh1WGwa8EAQYASABEgLx6vD_BwE

 

[Hayabslee]

Have you thought about replacing with something like these, there usually about 85 mm diameter


https://www.ledkia.com/uk/buy-basic...MI8rupk4iq3wIVArTtCh1WGwa8EAQYASABEgLx6vD_BwE

Not seen these before - will take a look.

 

[sparkwright]

As per a previous post, I've been changing existing GU5.3 MR16 halogen bulbs to LEDs (leaving the existing transformer in and not using any LED driver as they appear to be working).

A few people have said, I should simply do away with them, get rid of the transformers and simply convert each light to GU10 mains powered.

If the existing GU5.3 LEDs are currently working, is there any benefit in me taking the time to convert them?

YES, you won't have transformers conking out every five minutes.

 

[winston1]

Transformers don't conk out every five minutes. Only those nasty switch mode things do that, yes only the nasty ones, decent ones don't.

 

[ericmark]

Although today a simple toroidal lighting transformer it likely the best option if you really want 12 volt, this was not always the case, a transformers output depends on the input, and with quartz bulbs either under or over voltage would reduce the life of the bulb, the switch mode or pulse width modulated power supply however connected the voltage so bulbs would last longer, and also had a reduced inrush so less damage to switches, and if you were not worried about bulb life you could dim the bulbs.

So in the days gone by the so called electronic transformer was better than the toroidal transformer, this was one of the main reasons for extra low voltage, the supply was regulated and the element was thicker so 12 volt bulbs lasted longer than 230 volt bulbs.

However with 230 volt one could use cold cathode lamps which were like a fluorescent tube folded, so you have more bulb options with 230 volt, then came the LED, and the 230 volt versions again had better options.

There is a larger diameter bayonet lamps 75 mm rather than 50 mm called the GX53, never used any but it seems the whole of the 75 mm is lit rather then much of the area being used for cooling fins, the base looks as if it would cover the holes of the old MR16 and it still allows one to swap bulbs rather than whole fitting.

 

[Londoner2]

I don't know why people still use transformers but i guess its because of legacy wiring, changing that becomes a big job.

Swap the bulbs out with led ones, but the issue is the transformers could run hot due to low voltage in LED and hence overheat, that is what someone mentioned on this forum to me. I have a old gu5.3 mr16 fitting with 3 mr16 20w halogen bulbs, it was in the house from 2004 onwards. 1 bulb went so i replaced all with 4w led ones. However you get a slight buzzing sound which i think is the transformer, this seems to be overworking to deal with low loads.

I then put 1 old 20w bulb back in and left 2 leds in and hey presto buzzing gone, the plan is to change the whole unit next year.

 

[bernardgreen]

I don't know why people still use transformers

If the lamp is 230 volt and uses LED elements then an electronic power supply ( EPS ) is essential to convert 230 volt AC power to a controlled current through the LED elements. In most case this is a SMPS device. The voltage across the LED elements is determined by the LEDs and not by the power supply.

The EPS has to be built into the lamp bulb when the bulb is a 230 volt bulb. In many low cost bulbs the EPS is a simple circuit using capacitors, resistors and Zener diodes to control the amplitude of pulses of current through the LED elements.

 

[ericmark]

LED's are current dependent devices, to use them something has to limit the current or they would run away and burn them selves out, there are three basic ways to turn the current dependent device into a voltage dependent device, the circuits that convert from current to voltage dependent are called drivers.
1) A resistor, these produce heat but with a 12 volt device the LED is typically going to have 3 volt across them so 3 LED's and a resistor works quite well.
2) A capacitor, as long as frequency is steady with AC a set amount of current will flow through a capacitor, so this is a cheap method of control, normally also a few resistors to ensure there is no voltage remaining in bulb when you remove it, and to bleed some power without lighting LED's so they will not store a small amount of power from natural capacitive or inductive linking and flash every so often, and also it allows dimmer switches and the like to be able to work without a neutral.
3) A pulse width modulated controller, these are used to make the lamp more efficient, and also allow a larger voltage range, I have a LED bulb in outside lamp rated 85 - 300 volt, the other two return around 75 lumen per watt, but this method 100 lumen per watt or more. However they will not work with dimming switches, or any other device before them which modifies the supply, which includes another pulse width modulated supply to drop voltage unless fully smoothed.

In the main one of the three above is build into the bulb, although you can get external drivers. But in the main once packaged into a bulb the bulb is voltage dependent. However if the bulb is marked 50 Hz then that is what should be supplied, as we have no idea what is inside the bulb, again if marked DC 10 - 30 volt then we need to supply it with ripple free DC in the main from a battery.

The problem with 12 volt is although most have a simple resistor, we as the used don't know for sure if that is the case, so if marked 50 Hz then only way we can be sure of correct supply is a wire wound transformer, when we use a switch mode or pulse width modulated supply, likely the frequency is in kHz range, and if it does have a capacitor to limit current which is I admit unlikely, we can't use DC or kHz supplies, it has to be 50 Hz.

The rules at moment say if not dim-able it must be marked as such, so if the unit says not dim-able it is likely it has a pulse width modulated driver inside so is a better quality product.

There is also a problem that with a kHz supply it could become a radio transmitter, so not a good idea even with a unit rated 0 - 60 VA to use it to supply a LED. With units rated 20 - 60 VA unlikely you can find a LED to draw enough current.

This problem working out what can power what, means easy way out is simply to use 230 volt.