Led Conversion

[woodchopper]

The lights on my landing are currently 12v MR16 35w.
Can the lamps be changed to MR16 3w Led lamps without any problems or are the transformers rated too high?

[woodchopper]

Should read MR16 9w

[The Builder]

You just unplug the MR16s and plug in the LED equivalents, Wooders. That's the easy bit.

Transformers (properly called "drivers") can be a problem. It's a matter of trial and error. This week, I replaced nearly a hundred of them in a local pub. Only two of them flickered slightly, so the drivers will have to be changed as well. That can happen.

Sometimes, the old transformer can buzz. That's another possibility.

Purpose made drivers solve this problem, but adds to the cost.

No one likes 12v anymore - especially the LED suppliers. I would suggest stripping out the existing transformers and connecting 240v LEDs directly.

The only other expense is for the necessary fly-leads to connect them.

[woodchopper]

Do the drivers not change the voltage down to 12v anyway??

[Old_Geezer]

I stress I am no expert in the field of LED lamps, but in my day the voltage drop over any diode was much the same; so I'd expect little issue with the change. One thing you might want to check is the spec for the power supply. I'd assume it is supplying DC, and you'd need to be confident it can still work without issues with a reduced load.

[The Builder]

Yes, the voltage is stepped down to 12v, and the circuitry rectifies the current to DC.

Also, as OG has mentioned, it's the much reduced load that can cause the problems, if any.

[buildersmate]

Halogen lamp transformers produce a nominal 12V AC output, not DC. LEDs are a DC device. You can feed them from an AC supply because the LEDs do not conduct in the reverse direction, but it unlikely that they will last as long as the rated hours.
An LED driver is not only a DC device, (rectified as the boss says), but it contains control circuitry to produce an output an a constant current to minimise the forces on the device.
Additionally the older halogen transformer may buzz or create flicker because of the lopsided way it is being driven.
There is no risk in what you are doing, other than to the life of the LED stack.

[woodchopper]

Think I will go for the rip out the transformer option and install new led drivers - thanks for your help all.