Replacing MR16 with 3w led

I'm thinking of replacing a number of MR16 12v bulbs with the new 3w led

however it says that the transformer needs to be a minum of 3w.

the transformer i have is 10w-60w and minium load for dimming is 35w

I'm stating the obvious here, but still would like it confirmed

Thanks

A 10-60W transformer probably means 1 per lamp, in which case you'll probably have problems with only a 3W load connected to it.

You may need to replace the transformers with proper LED driver(s)

Many (most?) LED suppliers recommend replacing 'transformers' designed for tungsten halogen spot lamps with LED drivers. The outputs of the two may both be 12 Volts but the output wave forms may be very different.

Tungsten halogen lighting 'transformers' are usually switch mode power supplies. They 'chop up' the mains voltage and feed it to the lamps in chunks. The lamps are quite happy with that, providing the average voltage of the chunks and the spaces between them is near enough 12 Volts. The thermal inertia of the filament is enough to stop it seriously overheating before it gets to the end of each chunk, and the spaces between the chunks allow it to cool down a bit between each meal.

The size and shape of those chunks could give the internal regulators in LED lamps indigestion. They prefer a blander diet without big chunks that's closer to a true 12 Volts for most of the time.

Some halogen lamps use proper transformers that may be suitable for use with LEDs, but they are much less common than SMPSs The transformers are often round, and heavy, being stuffed full of big lumps of iron and coils of wire.