240v ~V~ LV halogen downlighters.

[andy1496]

Hi.
I'm about to have downlighters fitted almost everywhere in my (mainly) self build barn conversion.

The Sparky is coming on Tuesday to fit the downlighters so I now need to choose whether to go mains voltage or LV.

Am I right in thinking that the same wattage fitting will have the same brightness output whether they are LV or mains?

Am I also correct in assuming that LV fittings would use less electricity and consequently be cheaper to run?

If LV is cheaper to run would mains voltage fittings running the energy efficient led bulbs be as cheap as LV and would they be as bright?

Sorry for all the questions. I am basically trying to decide which is the best way to go with my lighting and the sparky has left it to me to sort/source.

Many thanks
Andy

 

[Big_Spark]

Couple of points:

• 1: Mains is LV (Low Voltage)
  
  2: 12V Lighting systems are ELV (Extra Low Voltage)
  
  3: Lower Voltage does not mean cheaper to run, and this is not the case at all with the lighting you describe.
  
  4: A 50W lamp at 230V will consume the same energy as a 50W lamp at 12V, however the 12V lamps appear to be brighter as more of their energy is converted to visible light apparently, they also have a whiter colour so the brightness of the lamps could be pyschological. ( I have never bothered to check as I have a life )
  
  5: 230V Dichroic lamps have about 30% shorter lives than equivelent 12V Dichroic lamps
  
  6: GU5.3 Lamps (12V) are easier to source than GU10 (230V) lamps, so getting replacements for 230V Dichroics could be an issue in future and should be considered.
  
  7: If you select 12V lamps, then the transformers should not be the cheapest available, they have a direct bearing of lamp life expectancy and can be a weak piont in the system. Aurora, Illuma and JCC seem to be the best, but I personally prefer 60Va wire wound units per light fitting instead of the electronic type. However many modern electronics types do help life expectancy of the lamps by filtering out spikes and surges on the supply.

The rest is largely personal choice.

 

[baldelectrician]

i would reccomend JCC trannys, 1 60va tranny per lamp.

In my experience if you use a 35W good quality (osram/philips/sylvania) lamp and a decent tranny the lamps will last longer and you will get tha same light from a 35 W 12V lamp compared to a 50W GU10 mains halogen.

(don't buy varlight dimmers as they can be problematic with 12V trannys)

JCC trannys have soft start - the lights ramp up brightness when switched on thus prolonging lamp life.

(I have 12V lamps in my kitchen and bathroom and I go through lamps about 1 set every 2-3 years in kitchen ans 18 months in bathroom)

 

[Lectrician]

ELV all the way!

Crisper, cleaner light.

JCC trannies, not had a problem.

Although, N+E own brand trannies are also very good, and have a 5yr guarantee.

I have 12v dic in my kitchen/bathroom/hall - not changed a lamp for 2yrs.

Mains voltage gu10's blow regularly, and more often in a steamy hot kitchen. The colour rendering is also crap.

Go for 50watt 12v lamps, ideal.

 

[andy1496]

Thanks chaps.
ELV it is then

Many thanks for the advice

Andy Brown

 

[baldelectrician]

As I said earlier I have 12V lamps in my kitchen.

I have 6 20W on one switch and will be changing them to 6 50W on 2 dimmers to control things better and male it brighter when required.

 

[ban-all-sheds]

The colour rendering is also rubbish.

My god - how did people manage all those years when all they had was tungsten GLS?

I'm with B_S on this one - if you fret about the colour rendering of LV vs ELV halogen lamps then you're wrapped too tight....

 

[Lectrician]

A main voltage halogen has crapper colour rendering than a standard GLS!

Compare the two side by side, and I know which one I would have....

If they produced the same light and benefits of a mains voltage......why are they made, and why are so many fitted? Not simply in homes, but shops, musiums etc?

 

[ban-all-sheds]

Because they came first.

I'm not saying they aren't different, what I'm saying is that in a house not a graphics design studio it really doesn't matter.

And if it does, then neither is OK - you need daylight simulating lamps, i.e. a colour temperature of around 6000° - 6500°K, and you won't get anywhere near that with any halogen lamp...