Lv lighting?

[mattc334]

Hi.
Could anyone tell me the pros/cons of LV down lights over mains ones,are there circumstances were one is better than the other or is it personal preference.
I would like to add two down lights to the end of a fluorescent circuit (5 single battons)would LV down lights be ok in this scenario.
Thanks for any help on this.

 

[Smugley]

ELV lamps seem to have a better/brighter light quality compared to LV ones of similar power. LV fittings are obviously cheaper and quicker to fit. In my experience ELV lamps tend to last longer because most transformers are kinder to them - ie soft start. However, similar things can be achieved by using intelligent dimmers on LV lamps too. Yes I am being pedantic with my use of LV and ELV terminology

 

[mattc334]

Thanks Smugley.
Your not being pedantic,it was my mistake not to posting correctly.
I think that awnsers my question i thought ELV was a better way to go,just wondered if using LV could cause a problem or if the reqs stated any preference.
Sitting here studying for 17th exam next week and my brain is frazeled could not find it in the book.

 

[Amp David]

With ELV light you have the extra time/costs involved with installing the transformers

 

[Smugley]

Other point regarding building regs is that ELV lighting is always notifiable except for "pre-assembled CE-marked lighting sets" whereas LV may not have to be notified if it's just an extension of an existing circuit and not in a special location.

 

[Adam W]

ELV lights tend to have small pins which can make a poor connection, and will involve a transformer somewhere which is an extra thing to go wrong.
On the flip side there seem to be a wider range of ELV lamps available.

 

[smartalek]

Elv has the added problem of transformers burning out.personally I'd just just have lv in most rooms but selv in bathrooms

 

[Amp David]

Personally have never yet had a transformer pack up on me

 

[electricAl]

Electronic tranformers are largely reliable these days (decent quality ones) if they`re installed correctly. Lack of adaquate ventilation is the most common cause of failure.
As stated, ELV (nice to see a bit of pedantism) lamps themselves offer better longevity, but this is mostly due to the increased filament thickness - compared to mains voltage (LV) If you do the maths, its easy to see an ELV lamp must present a significantly lower impedance than an LV of the same rating.
Compared to LV`s, they`re more efficient in terms of consumption to lumen output too, & produce a much cooler (whiter) light thats especially suited to bathrooms etc. The majority of D/L`s i fit these days are CFL`s & LED`s. Particularily in bathrooms, ELV`s are still preferable to CFL`s due to their instant start & generally crisper output, but of course still lose out to LED`s of the likes of Cree MCE`s.
ANd nice to see Smugley stating the often forgotten fact that ELV installs are notifiable, unless they`re in a unmodified kit form. Think that`d be news to thousands of DIYers - "its alright, they`re only low voltage mate"

 

[davelerave]

the quality electronic trafos will have SC,O/L and thermal protection

the LV gu-10's are handy as you have the option of led,cfl or halogen bulb


if it's definitely halogen- 12V is prob better(as already said)

 

[Marvo]

ELV lights tend to have small pins which can make a poor connection.......

Yeah, I never figured this out. They use the thin pins on ELV lighting which draws twenty times the current of LV lighting of the same wattage. Why on earth is that?

 

[Adam W]

Does an "extra-low voltage lighting installation" include swapping a LV downlight for an ELV one?
I assumed it just meant running an entire or substantial part of a circuit on ELV supplied from a central source, eg a battery.