12 Volt downlights require a transformer to step the voltage down from 240 volts down to 12 volts. There are two types of transformers
If the lamp is incompatible with the electronic transformer then there are two options. 1) replace the transformers with one designed to drive LED bulbs specifically, or 2) rewire the fittings so that there are two fittings or more per transformer. The only problem with the latter approach is that if someone at a later date replaces the LEDs with halogens again, the transformers will be overloaded and will shut down.
Electronic transformers that are LED-compatible are usually labelled as such.
Fixtures that use an iron core (ferro magnetic) transformers can generally be used with LED-lamps without modification.
Transformers use energy to operate adding to the energy requirements of the lighting without providing additional lighting. The older iron core transformers were very inefficient, adding up to 15 watts to the 50 watts used by the globe. Electronic transformers use as little as 2 watts (eg Redback transformer).
Do I need an electrician to replace transformers?
In some cases you will need an electrician, in other cases you won't (if you are competent in the roof cavity and rearranging plugs). If downlights were fitted with a standard appliance plug that plugs in to a power point in the roof space, then you just plug in new fittings (although you might have to fit a lead to the new fittings).
If they are hard wired, then you will need an electrician.
What am I looking for in a quality transformer or LED driver?
Transformers need to draw a small amount of power (ideally less than 4 watts) and have load range allowing them to operate at lower power demands.
Hardware stores and lighting shops sell transformers.
41 Victoria Street
Ph (03) 6234 8066Globes
76 Argyle Street Hobart
45 Burnett St 7000 North Hobart
Ph 6231 0002
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