The Boss (wife) wants spots putting into one of our ceilings - but I'm not sure if I should go for the 240V version or the 12V version.
Screwfix do a pre-wired version of each type - but which is best/ safest/greenest?
I know on the plus side the 12V lamps are cheaper and on the minus side the distance from the transformer is limited and they need a special dimmer (if this is needed) but apart from that what are the pro's & cons of each system?
12V wins every time:
More light output per watt, whiter spectra and better colour rendition. More robust filament so more vibration resistant. Longer bulb life. You also get the option of using dichroic bulbs with appropriate fittings. This give better colour rendition again and projects less heat forwards from the bulb.
Electronic dimmers and transformers work ok together (you need a halogen rated dimmer for mains ones anyway).
The only down side of the 12V ones is the requirement for the transformer. If you want you can wire everything as if you were using mains, and then have one small transformer per bulb that just pushes into the opening in the ceiling.
I think I was heading down the 12V route - but I hadn't thought about wiring everything as if I was using mains, and then have one small transformer per bulb. I guess this eliminates the distance from the "central" transformer issue - How would I go about dimming in this configuration?
Kev
Halogen downlighters - or any downlighters really - can't be described as 'green' ;-)
NT
This was asked just recently
Exactly the same, dimming is done on the 240V side of the transformer(s) regardless of if its one central one, lots of individual ones, or somewhere between the two.
You've got them all. except lifertime on the 12v stuff is about ten times what it is on the 240v bulbs..
Considering the hassle of bulb changing, that alone is worth the marginal extra cost.
Get overrated dimmers and use electronic transformers marked as 'suitable for dimming'
On the big negative side, whether you are talking about GU10 mains halogen or 12V halogen they soon add as far as power use is concerned. I've recently had to fit out a shop, living room and a kitchen and was ordered to use a combination of downlighters and spots.
I've tried all of the combinations and they all have their negatives. The GU10 mains don't last long and they provide poorer illumination than the 12V equivalents.
Cheap transformers and cheap switch mode PSUs burn out at horribly regular intervals. Almost anything bought from B&Q seems suspect.
The 10x 12V MR11 halogen downlighters used in the kitchen provide optimum illumination, but consume 500 watts which is taking the mickey as far as I'm concerned. In the shop the consumption of the GU10 downlighters was pushing the consumer unit to its limits and causing problems with heat.
In the living room we started with 240V R50 downlighters, and my wife stil prefers the light from them but this was running to 160W and that also seemed excessive.
At the moment I'm trying a mix of these:
I wouldn't buy from the site given above. Their prices are silly. Most of these bulbs are available from Tesco for about £1.70-£2.00 each.
If you go for one big transformer, then don't overrate that too much since they have a minimum load as well. Without enough load they won't dim properly.
(I have used a 250W transformer with 4 x 50W bulbs - you need at least 3 working bulbs to make it work correctly).
great article .. if you want an opinionated rant against halogens.. a good contribution for a regular uk.d-i-y thread, to get soem discussion going, but a poor piece of work to submit to a wiki.. gave me a good laugh the first time I read it.
crap for providing any real information
cheers
As is your post. Try countering some of the arguments in the article instead.
Perhaps the majority who fit these things do so do purely to follow fashion. An article giving the true picture is no bad thing. If there are any inaccuracies please list them.
If having read - and understood - the article one still wishes to use them for cosmetic reasons, that's your prerogative.
Not quite every time - I haven't see any (Non LED) low energy 12v lamps!
I installed GU10 (240v) downlighters in our Kitchen, so I could then use the megaman 11w lamps in them.
Warm-up time is not the greatest, but we don't have an issue with that.
Sparks...
Whilst I agree with much of that article and it mirrors postings I've made here (although there are some errors in it), I also agree that it's inappropriate as WiKi content. It is an opinionated rant, and that's bad practice for a Wiki or FAQ. It completely discredits itself, and the valuable message it tries to put across is consequently lost.
Hey this is newsnet after all... most of the posts contain very little information, and large amounts of rant. :-)
An article giving the true picture is a great thing, as is presenting good facts and references, along with some balanced reasoning. This wiki article isn't about informing people of the choice of halogens or why 20W bulbs are often as effective as 50W ones for spots or downlighters. Or that they could replace that monster 500W bulb that lights up the neighbourhood with a slightly more respectable 200W beast. (OK it just just about cover that, just misses out the alternative halogen choice.)
or how to handle bare halogens
or consideration for beam quailty, 35 degree of 50 degree
for some reason when I first saw this article title that is the sort of information I expected to see in it especially in a d-i-y wiki. My biggest disappointment was with the factual information content...
The diy wiki should be a good thing as well, but only if people contribute and update articles to provide a balanced opinion. I probably fall down here because it's not something I've generally got the time to do and back up what I'm talking about here. In general I take my hat of to people who contribute the time and effort to write good wiki articles
You know what --it is pretty difficult to come up with concrete inaccuracies because so much of the article is general opinion, or reference to things that may be strictly correct (potetentially in extreme cases) but are not quantifiable... for example they /could/ increase fire risk, they /could/ blow MCB's, they _will_ hurt your eyes if you look into they (shocker), they /could/ increase your cancer risk, /if/ you buy crap bulbs with short life expectancy then you'll need to replace them. or if you use a 200W worth its is going to cost you =A3x. over y years. can't argue with the arithmetic.
Indeed...however, there isn't a great deal of information to take in and understand. There is a lot of opinion. there are a few unquanitifed interesting statements, there are some numbers wisely chosen to illustrate the points being made.
Being a wiki and web based perhaps it would be good to find some links to allow people to form there own opinions based upon some good information and data.
Don't get me wrong I reckon 90% of people use halogens very badly. They are sold some strip of 4 x50W monsters and stick them up with out thinking. But there are places where they are very useful and do provide excellent lighting.
But I also think something which should be a general article in a diy wiki on halogens should contain at least some factual information relevant to the diy community
cheers
David
Spot on
I think the wiki is a great idea, but it should be for factual content and references. Of course by not actually commiting anything to the wiki I'm kind of sitting in a glass house here.
At the moment many articles are lacking in decent links providing further details, and because there are many areas of diy that do produce good discussion and opinion I also reckon a couple of links to some of the threads here would be of benefit to give a flavour of the opinions relating to, for example, boiler choice, or lighting :-)
cheers
David
Yup, I would go along with those comments. So I thought as my first wiki contribution I would add to that article a bit, and see if we can actually get some more practical information in there, as well as balance up the tone a little. I have not added any external references as yet, but have a second read and see if you think it is a more useful reference now. If the consensus is that it is, I will look out some references and links.
So get there quick before someone reverses out all the changes ;-)
This is somewhat less biased than the original, but I would still take issue with several points that remain:
- Glare. That depends on the method of use of lamps and the surfaces in the room
- In the costings, there should be a mention of the heat contribution from lighting
- The suggestion that fluorescent lights can provide equivalent light aesthetically or even functionally. At best, that is a matter of opinion
- The suggested risk of sin cancer. For typical downlighter lamps (e.g. GU and GZ types) this is non existent because they are shielded. Secondly, the pattern of use is normally with lamps in the ceiling. Studies done in this area were with unprotected desk lamps which are at much closer proximity to individuals, can be left unshielded easily and are used for longer periods. In short, this is a bogus argument in connection with domestic downlighter applications.
I would agree with all of that.
Also, the costings were muddled.
I couldn't actually work out which WAS cheaper.
For me the prime benefit is in low bulb replacement costs for 12V stuff..the bulbs are now similar in price to ordinary ones, but last at least 10 times longer.
HomeOwnersHub website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.