[Question] 12V halogens replaced with LED's

[davidstj]

Hi.

I've replaced 180 W worth of 12V halogens (50's and 20's) with (if I remember correctly) about 25 W of LED. Should I get the original 200 W transformer replaced with a smaller one or just leave as is and am I "wasting" electricity with the original 200 W unit or does it only supply what the LED's are drawing?

Cheers,
Trevor.

[bergie]

it only supplies what the led needs.so no wasting

[AndyD]

If it's one of the old type wire wound transformers then it might have slightly higher 'iron losses' which are basically inefficiencies because of the lower load LED lamps but it will be an insignificant amount and definately not worth buying a new transformer.

Just for future reference you can sometimes just use 230v LED lamps and remove the transformer entirely. This might give you a small added bonus saving but you need to get an electrcian to check first that the light fittings are safe for use with the higher voltage lamps.

[davidstj]

Thanks.

[Sparks]

The AC transformer for the LED's?

[AndyD]

Most of the MR16 bi-pin LED lamps will run on 12VAC or 12VDC but it's always worth checking the manufacturers data.

[davidstj]

The AC transformer for the LED's?

The original 220 AC transformer suplying 12V to the downlights (previously halogens)
Great big thing about half the size of a shoebox.

[AndyD]

Yep, sounds like an old wire wound type. I personally wouldn't replace it. Doing so might save you a few cents each month but it would take many years probably to recover the outlay of installing a new one plus the old wire wound transformers tend to be more reliable.