Do MR16 Led bulbs require a LED driver or a transformer?

[captaincaveman]

Hi guys,

Quick question regarding 5x MR16 (Gu5.3) Led bulbs in downlighters. The customer used to use halogen but has moved over to LED. They had stopped working due to a faulty 12v transformer
I've just replaced the transformer with a constant voltage driver (1-25w) but with any more than 3 bulbs inserted then they all seem to flash. Due to time I left it working with 3 and was due to return to sort it but she says her son has replaced the driver with a 12v transformer and they are all working fine!

MR16s don't have built in drivers do they?

Cheers in advance

 

[Octopus]

MR16 LED's require an appropriate transformer.

Not all existing transformers "like" LED's

 

[SparkyAndGeorge]

Why dont you replace the lamp holders with GU10's and get some GU10 LED's. You can then disconnect the driver/tranny giving one less thing to go wrong.

 

[stoneworld]

from what i can see some of these 12v led lamps will run from AC or DC. They have a rectifier on the input so AC will be rectified to DC and a reverse polarity DC will be put right. then there is a DC-DC converter and if I remember correctly the lamp will run from something like 6-30v

 

[buzzlightyear]

MR16 LED's

try Philips LED 12V MR16 Dimmable Lamp 8W 621lm

 

[captaincaveman]

Cheers guys.
Sounds like forgetting drivers then I guess... I was under the impression LEDs damaged transformers or the bulbs and they needed drivers.

I'm not keen on LED technology. It seems fickle with a lot to be ironed out still. There's so many brands out there and hard to know which are reliable (I'm still waiting 25000 hours to see if one will last that long) and then you have to throw drivers and dimmers into the mix (and don't start me on LED dimmers!)

 

[captaincaveman]

P.s. I suggested GU10s but the customer didn't want them

 

[davesparks]

I'm not keen on LED technology. It seems fickle with a lot to be ironed out still. There's so many brands out there and hard to know which are reliable (I'm still waiting 25000 hours to see if one will last that long) and then you have to throw drivers and dimmers into the mix (and don't start me on LED dimmers!)

LED technology is pretty sound, it's the way it is used/applied that leads to problems. Trying to make new technology like this work identically to old technology doesn't work.

An LED light fitting which is designed specifically for LED from the outset with the correct cooling works very well. An LED and driver circuit squashed into an existing lamp package such as GU10 which was designed for something which needs to stay hot to work properly is never going to work as well.

Dimming LED is also very reliable if you design the system to work with the technology rather than trying to force it to work with old methods. Feeding an LED driver circuit with a dimmed supply is never going to be perfect because you are giving the electronics which control the LED a chopped up or reduced voltage to power them. Drivers which have a permanent supply to power them and a seperate control signal input are the way to go with LED, this doesn't have to be anything fancy, simple 1-10V control is fine.