Thread: Downlight transformers keep blowing.

were we are renting 5 yrs now the downlight globes themselves have blown at least 2 every 6 months the transformers have been checked and are about 17 yrs old. This on one circut only with 2 lights. While the lounge room has 4 and only one has ever gone.

Not long ago a media TV show along with firebrigade gave notice as to dangers of transformers over heating causing home fires.

Maybe you could replace the lamps with LED lamps, they draw a hell of a lot less power and won't run your transformers so hot.

Cheaper to run too, 12v halogen downlights are the least efficient form of lighting known to mankind...

hi - most common recomended transformers from lecos is an Atco possum electronic - make sure each transformer is only connected to one light each. the 12v cable also should be short as possible and heat rated wire (dont think this would be making a difference - but its a starnge world out there!

Second, i would get decent globes - the ones recomended to me were osram decostar ES (IR?) 35w globes. these are as bright as any 50w but only use 35w and will last 7000 hrs or soemthing ludicrous!.

Final option, if all that seems like a hassle, then using a dimmer (trailing edge) and just turning the light downthe tiniest little but (just so you can tell the dimmer is operating) - this reduces stress by quite a bit
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BTW, they arent iron core transformers are they?

Are the supply transformers mounted the minimum required clearance from the recessed luminaire?

Originally Posted by Dusty Dave

Maybe you could replace the lamps with LED lamps, they draw a hell of a lot less power and won't run your transformers so hot.

Cheaper to run too, 12v halogen downlights are the least efficient form of lighting known to mankind...

LED's dont cast enough light to replace a halogen (yet) - maybe a 20w halogen would have a direct replacement, but by and large LED's require 3 to 4 times more lights.

halogens are more efficient than std globes in nearly all applications and are the best option for task lighting. general space lighting is the preserve of CFL's (if you are happy without any dimming capability)

Originally Posted by pharmaboy2

halogens are more efficient than std globes in nearly all applications

You're kidding right? 50 watts for a little puddle of light on the floor?!

How many rooms have you seen lit by a single halogen downlight?

They look great but they certainly aren't about efficiency...

Throw the damn things out and get fluro downlights!

Originally Posted by Dusty Dave

You're kidding right? 50 watts for a little puddle of light on the floor?!

How many rooms have you seen lit by a single halogen downlight?

They look great but they certainly aren't about efficiency...

http://en.wikipedia.org/wiki/Lightin...ing_efficiency

13.8 lm/w incandescent versus 17.6 lm/w halogen.

so compare a 100w halogen non reflector with a 100w incandescent and the former will be a 1/5 dimmer give or take. If you are comparing down lights then it should be same for same .

No-one would use a 50w reflector 60o dowlight as space lighting, so the comparison is mute - yoy should compare like with like.

the table is pretty self explanatory I think.

Originally Posted by pharmaboy2

No-one would use a 50w reflector 60o dowlight as space lighting, so the comparison is mute - yoy should compare like with like.

Isn't that precisely what MOST halogen downlights are being used for?! Or am I missing something - exactly what is it on all these people's floors that's so exciting?!

I've seen plenty of houses which are using hundreds of watts of power in downlights right through the house because they 'look nice'...

yes, but all i said is that halogen is more efficient than incandescent - this is factually true, and pretty much incontrevertibly the case.

What you are saying is that a halogen downlight isnt as efficient as a 50w hanging globe in a room - well - the comparison you are making is actually an all round emitting space light with a downlight - its the method of delivery that is different, not incandescent versus halogen - see?

generally, if you require space lighting (eg loung room, family room etc) thenstd fixtures with warm cfl's maybe 22w or so do the job. If you are lighting a kitchen or benches, then halogen, if you want dimming, halogen or incandescent. down lights also work pretty good onto timber or tiled floors where they reflect quite a lot of light.

A well designed home should use all types depending on needs.

though in my own home i dislike all our cfl's because the light is too white - halogen is a very accurate light for colour.

My sister has 8 of these bloody awful Halogen downlights in her living room...all of them 50W each & 60 degree. Unfortunately, most other rooms in her house have the same downlights. One day, she complained to me why her electricity bill was high. I explained to her about the lights & the extremely "lossy" (& dangerous) transformers & she began to understand.

As a former Chief Engineer of a hotel in Sydneys' CBD (1998), I banned these Chinese transformers & designed each room/suite to have these awful lights controlled by one Australian made transformer. End of transformer problems. Mind you, this was a little before the time of so called "electronic" transformers.

Also, back in 1998, Australia did not scrutinise all electrical imports from "developing" countries. Essentially, "developing" countries were allowed to import their electrical goods as long as they met voltage & frequency standards...not "quality" standards.