LED Bulb Thread

Caporegime
Joined
21 Jun 2006
Posts
38,372
Does anybody make DC LED bulbs, say 48Vdc or 110Vdc.

Given the low power consumption for LED lighting, a sort of "Whole House" UPS driven directly from storage batteries, at least as far as lighting is concerned anyway. Becomes a realistic possibility.

However, not sure that doing a whole house at 12V would work too well.

don't see the point. either you have proper battery storage and use that or buy a torch which is substantially cheaper than spending hundreds/thousands on re-wiring your house and batteries.

i might get an electric vehicle and double up on that and use as power storage for the house.
 
Soldato
Joined
13 Jul 2004
Posts
20,079
Location
Stanley Hotel, Colorado
I love the idea of it but the ease at which its done is another thing, ideal project for an off grid type setup. In Wales there is unique planning legisilation where you can build on green belt land possibly anywhere so long as its all in self sustainable and requiring no connection on any utility. The amount of money you could save on the housing going totally DIY is gigantic and could justify ideas such as that quite easily imo, but its a big ask for most laypeople.
 
Soldato
Joined
25 Oct 2009
Posts
6,672
Location
Caerphilly
Whats the go to LED bulbs or website please?
I've had a lot better luck with Philips LED bulbs than the likes of Lumilife etc.
Mum is wanting to change the vast majority of bulbs in the house.
 
Soldato
Joined
25 Sep 2006
Posts
14,358
Looking for a 2 core dimmer for 45w~ of LED garden lights. Preferably in-line. IP rating not required as it'll be indoors.

Found a few online but not sure as to their lower end threshold.

Would I be able to use a regular trailing edge dimmer with 2 core successfully? Thinking so but not well versed in this area.

There is a mains plug and presumably a transformer on the lights.
 
Last edited:
Soldato
Joined
1 Mar 2010
Posts
21,926
*THREAD REVIVAL - MOST OF MY V-TAC'S ARE DEAD 2 YEARS LATER*

I need some new gu10's - most of my v-tacs have been refunded, so I may still use the brand again; integrated ceiling leds are still expensive.
the kitchen has 2/6 , bathroom 2/3 still living, which is helping with energy saving too.

BUT - who buys the 110degree gu10s does the light really manage to get out of embedded ceiling holders ? and illuminate surfaces below sufficiently.

The 110's without a lense probably don't have the smd leds as closely spaced, so perhaps have better heat dissipation and longevity.
 
Soldato
Joined
29 Sep 2004
Posts
3,105
Location
Wilt of the Shire
Since getting a smart meter I've noticed that when I use our uplighters it goes amber. They currently use halogen bulbs so looking for an LED replacement. Current bulb is 300W R7S, I can see loads of them on amazon etc but not sure which one to go for so if anyone has bought any recently let me know. These are the last bulbs in our house that are not LED so would be nice to change them.
 
Associate
Joined
24 Mar 2018
Posts
1,460
Location
Brighton
Anybody recommend 2700/3000K GU10 LED's 60 wide for kitchen spot lights, Also looking to replace uplight R7s with dimmable LED. I see some off-set LAP R7s at SCREWFIX.
But the last time I tried LAP GU10's I got MAX 6 months out of them, also very poor flickering nightmare.
 
Soldato
Joined
18 Oct 2002
Posts
14,152
Location
West Midlands
Anybody recommend 2700/3000K GU10 LED's 60 wide for kitchen spot lights, Also looking to replace uplight R7s with dimmable LED. I see some off-set LAP R7s at SCREWFIX.
But the last time I tried LAP GU10's I got MAX 6 months out of them, also very poor flickering nightmare.

Just used 14x Philips Master Value 6.2-80W Dimmable LED GU10 Warm White 120° (929002210099) for a very large kitchen, the previous electrical installer did a pee poor job of lighting the place properly, and there were dark/dim spots all over the place and the ceiling wasn't really that high so went with 120°, it is a nice bonus have such a good CRI on those as well.

 
Associate
Joined
24 Mar 2018
Posts
1,460
Location
Brighton
I'm thinking 120 might be a waste because they sit inside a casing on a three way which we have 2 of in a 18x13ft, are yours ceiling mounted?
I should have been more clear about my setup, those look good though!
 
Soldato
Joined
18 Oct 2002
Posts
14,152
Location
West Midlands
I'm thinking 120 might be a waste because they sit inside a casing on a three way which we have 2 of in a 18x13ft, are yours ceiling mounted?
I should have been more clear about my setup, those look good though!

It wasn't my kitchen, I just sorted the issue as the lady who it belongs to knows nothing about how to light a place correctly. Those were indeed in-ceiling spots, so directly down firing, but I have used 120° in other situations/fittings as 36° just wouldn't have cut it and I'd rather have slight overlap than big dim gaps.

For complex situations then I'd draw up a lighting simulation, but with the size of your room and where the bulbs are a piece of A4 paper and a compass/protractor would do the job as long as it is all to scale.
 
Associate
Joined
24 Mar 2018
Posts
1,460
Location
Brighton
I'm thinking 120 might be a waste because they sit inside a casing on a three way which we have 2 of in a 18x13ft, are yours ceiling mounted?
I should have been more clear about my setup, those look good though!

It wasn't my kitchen, I just sorted the issue as the lady who it belongs to knows nothing about how to light a place correctly. Those were indeed in-ceiling spots, so directly down firing, but I have used 120° in other situations/fittings as 36° just wouldn't have cut it and I'd rather have slight overlap than big dim gaps.

For complex situations then I'd draw up a lighting simulation, but with the size of your room and where the bulbs are a piece of A4 paper and a compass/protractor would do the job as long as it is all to scale.
Great Tip... It's like pulling teeth choosing LED bulbs! "Lamps if you live in blackpool"
I have found what might be a solution. Long Neck 75mm GU10 REXEL that should bring me flush, I've also just found extenders for GU10's as well. hmmmm
 
Last edited:
Man of Honour
Joined
29 Jun 2003
Posts
34,515
Location
Wiltshire
Since getting a smart meter I've noticed that when I use our uplighters it goes amber. They currently use halogen bulbs so looking for an LED replacement. Current bulb is 300W R7S, I can see loads of them on amazon etc but not sure which one to go for so if anyone has bought any recently let me know. These are the last bulbs in our house that are not LED so would be nice to change them.
Blimey not surprised it goes orange, you could bring in ships with that thing :p
 
Associate
Joined
17 Jan 2003
Posts
1,058
Anybody recommend 2700/3000K GU10 LED's 60 wide for kitchen spot lights, Also looking to replace uplight R7s with dimmable LED. I see some off-set LAP R7s at SCREWFIX.
But the last time I tried LAP GU10's I got MAX 6 months out of them, also very poor flickering nightmare.

I have about 30 4 year old LAP GU10's - no flicker. 1 has failed - replaced under warranty

Given that the warranty is 3 years why didn't you get replacements ?
 
Soldato
Joined
1 Mar 2010
Posts
21,926
Also looking to replace uplight R7s with dimmable LED
have been looking at these philips to replace some metal halide 70w rx7's - but not sure they are slim enough for existing fitting.

also although marked dimmable , like below they may change colour frequency when you did them - sorry, but imhop crap, basically,
the “DimTone” feature could be useful. This is a LED feature that creates a warmer tone once light is dimmed down to lower intensities WTH
they are trying to make a sales benefit out of a deficiency, so if anything looking at more expensive philips expert colour, gu10's, really disappointed when I found out.

I'm thinking 120 might be a waste
agree, but couldn't find any reasonably priced narrower beams, so bought these v-tacs, in june, for the time being
the beam requirement, anyway, is something like 70% of the lumens must be emitted in that 'cone'
 
Soldato
Joined
18 Oct 2002
Posts
14,152
Location
West Midlands
they are trying to make a sales benefit out of a deficiency, so if anything looking at more expensive philips expert colour, gu10's, really disappointed when I found out.

You do realise that it is designed in, it is not a deficiency, having the ability for LED's to behave like dimmed incandescent light bulbs has been wanted for ages by many people. If you don't like it buy bulbs that don't offer that function, pretty simple really.
 
Soldato
Joined
1 Mar 2010
Posts
21,926
people don't want that, they want same frequency at lower intensity, unfortunately without expensive electronics you just get reduced frequency (and CRI), philips expert colour don't mention dimtone,
but are less efficient.
(e:philips, at least, are honest about dimTone effect )

earlier post on gu10 beam angles

lights (had looked this up because it explains why gu10s often seem to have poorer output than globe shaped bulbs - 50% of light can be outside advertised beam angle)
The average energy efficiency of LEDs quadrupled between 2009 and 2015, and prices dropped significantly
he average household in the EU bought 7 light sources per year in 2010, 4 per year in 2020, and this figure is projected to drop to less than 1 per year by 2030.
Class limits are proposed with a 25 lm/W difference between consecutive classes: all light sources above 210 lm/W are class A. All light sources below 85 lm/W are class G
— for directional light sources with beam angle ≥ 90° it is the flux emitted in a solid angle of π sr (corresponding to a cone with angle of 120°);
— for directional light sources with beam angle < 90° it is the flux emitted in a solid angle of 0,586π sr (corresponding to a cone with angle of 90°)
 
Last edited:
Soldato
Joined
18 Oct 2002
Posts
14,152
Location
West Midlands
people don't want that, they want same frequency at lower intensity, unfortunately without expensive electronics you just get reduced frequency (and CRI), philips expert colour don't mention dimtone,

Erm... For ages I wanted LED bulbs that I could dim in my wall lights with a lower Kelvin rating, so 2700K down to 2200K fully dimmed, like I used to get from a filament based bulb. Stop telling me what I want, when I know exactly what I want and that is now easily available.
 
Soldato
Joined
1 Mar 2010
Posts
21,926
In the bathroom or kitchen where all my gu10 are I don't want a colour spectrum shift on dimming (at the very least I'd want CRI value maintained too)
if I had gu10's in living room I'm more sympathetic to a red shift, but that does not play well with 6500K tv light backlighting.


anyway here is a technical paper which explains additional control mechanism (=> COST) which would be required if you want to maintain spectrum on dimming a combo of amplitude & pwm modulation;
so when manufacturers provide spectrum shift that's the low cost option, if they can turn that into a marketting win kudos to them.

In order to dim LEDs the pulse width modulation (PWM) or amplitude modulation (AM) dimming scheme is typically used. Previous studies show that these dimming schemes can have opposite effects on diodes peak wavelength shift. An experimental study was conducted to test the behavior of InGaN diodes and phosphor-converted white diodes under hybrid PWM/AM modulation. Feed forward control schemes that provide stable peak wavelength position during dimming and the ability to compensate the thermally induced color shifts and the decrease of the luminous flux are investigated.
 
Back
Top Bottom