Reply to: Anyone installed 12v internal lighting?

[NotAllThere]

...
Actually I think the fittings themselves are failing, because a brand new fluorescent bulb I fitted at the weekend also didn't work...

Have you tried replacing the starters? Something like this:

I don’t think you really want strip lights - those are ones where you can change colours, etc.

Yeah, you do. They're fun.

We're using some for the sfx of our next theatre production. We've a 5m strip where each led has its own micro-controller - so separately programmable.

[DimPrawn]

And since it be AC wot we're talking about, the Real Power is V*I*cos(theta).

This is wot the old fashioned electricity meter records.

Feck nose what these new fangled electronic meters record, but there is much muttering about them being strikingly inaccurate.

<ZG in "pretending to be able to remember all this tulipe from 40 years ago and don't get me started on per unit calculations coz I never understood those to begin with" mode>

Ah power factor calculations, them was the days....

[zeitghost]

Um, no.

Georg Ohm’s law was V=I*R (Volts = Current (amps) * Resistance)
Wattage doesn’t come in to Ohm’s law.

P=V*I (Power (watts) = Volts * Amps)

...you should have asked your accountant electrician

And since it be AC wot we're talking about, the Real Power is V*I*cos(theta).

This is wot the old fashioned electricity meter records.

Feck nose what these new fangled electronic meters record, but there is much muttering about them being strikingly inaccurate.

<ZG in "pretending to be able to remember all this tulipe from 40 years ago and don't get me started on per unit calculations coz I never understood those to begin with" mode>

[OwlHoot]

Why would you want fluorescent tubes even if they are LED in your kitchen?

Well it has fluorescent tubes now, and I'm not a fan of fancy, poncey spotlights that light up the ceiling and leave the rest of the room in stygian gloom.

Without wanting to sound facetious, I want to see clearly what I'm doing! Also, my kitchen is pretty large, about 30 by 20 feet. So a couple of normal LED bulbs probably won't cut it.

But I'd also like dimmable LED tube lights, in case I don't want or need the full glare, and to save more electricity.

[northernladuk]

Yes, I was about to post that I found an LED Hut page on what they call "tube lights", and these look like the fluorescent light replacements:

https://www.ledhut.co.uk/commercial-...be-lights.html

Why would you want fluorescent tubes even if they are LED in your kitchen?

[OwlHoot]

I don’t think you really want strip lights - those are ones where you can change colours, etc.

You could start off with something as simple as replacing your fluorescent tubes with LED tubes, e.g.
https://www.ledhut.co.uk/t8-18-watt-...0mm-3000k.html
(I’m not an electrician, I don’t know the size/model of your current tubes, but the above is just to give you an idea)

Yes, I was about to post that I found an LED Hut page on what they call "tube lights", and these look like the fluorescent light replacements:

https://www.ledhut.co.uk/commercial-...be-lights.html

[WTFH]

OK here's a simple example.

I have a four horrible ("transport cafe c. 1970") fluorescent light fittings in my kitchen ceiling, and three of the four bulbs are on the blink, literally.

Actually I think the fittings themselves are failing, because a brand new fluorescent bulb I fitted at the weekend also didn't work.

So I'd like to rip all these out and replace them with LED strip lights (preferably dimmable). But looking at the "LED strip light" page at https://www.ledhut.co.uk/led-strip-lights.html, already my head is spinning with the bewildering complexity of it all!

I mean there are literally dozens and dozens of LED widgets, and I've no idea what most do or why or when they would be needed

Also, very few of the items on that page, in fact come to think of it none that I can see, look like actual light bulbs!

So can anyone kindly suggest the best items of LED kit from that or another LED Hut page to replace a single fluorescent light fitting with the LED equivalent fitting in the ceiling and the LED bulb of equal brightness (equivalent to say a 120W incandescent bulb) ?

I don’t think you really want strip lights - those are ones where you can change colours, etc.

You could start off with something as simple as replacing your fluorescent tubes with LED tubes, e.g.
https://www.ledhut.co.uk/t8-18-watt-...0mm-3000k.html
(I’m not an electrician, I don’t know the size/model of your current tubes, but the above is just to give you an idea)

[WTFH]

Anyone installed 12v internal lighting?

It's all about the wattage. Ohms law innit.

Um, no.

Georg Ohm’s law was V=I*R (Volts = Current (amps) * Resistance)
Wattage doesn’t come in to Ohm’s law.

P=V*I (Power (watts) = Volts * Amps)

...you should have asked your accountant electrician

[OwlHoot]

OK here's a simple example.

I have a four horrible ("transport cafe c. 1970") fluorescent light fittings in my kitchen ceiling, and three of the four bulbs are on the blink, literally.

Actually I think the fittings themselves are failing, because a brand new fluorescent bulb I fitted at the weekend also didn't work.

So I'd like to rip all these out and replace them with LED strip lights (preferably dimmable). But looking at the "LED strip light" page at https://www.ledhut.co.uk/led-strip-lights.html, already my head is spinning with the bewildering complexity of it all!

I mean there are literally dozens and dozens of LED widgets, and I've no idea what most do or why or when they would be needed

Also, very few of the items on that page, in fact come to think of it none that I can see, look like actual light bulbs!

So can anyone kindly suggest the best items of LED kit from that or another LED Hut page to replace a single fluorescent light fitting with the LED equivalent fitting in the ceiling and the LED bulb of equal brightness (equivalent to say a 120W incandescent bulb) ?


edit: Studying that LED Hut strip light page some more, it appears that what they refer to as strip lights are those silly little "Christmas tree" lights like a tape measure with illuminated patches along it. But by strip light in the above I mean a proper LED replacement for a fluorescent light (if such things exist yet).

[WTFH]

HUH?!

How can that be? I was told they use so little electricity you could practically leave them on all the time without worrying about your electricity bill.

I mean that's the whole point of going with 12V bulbs surely (besides the not electrocuting yourself in the bathroom thing).

OK, let’s look at it like this:
You pay for your electricity in kWh (that’s kilowatt hours)

A 10 Watt LED requires 10W of power.

Let’s put 6 of them on a circuit (just to make my maths easier in my head). That’s 60W of power.

On a 12V circuit, you are using 60/12 = 5 amps
On a 240V circuit, you are using 60/240 = 0.25 amps

You’re still using 60W of power, no matter what voltage of supply you use.
But...
To convert 240V down to 12V requires a transformer. Transformers are not 100% efficient. Let’s say you have one running at 90%. That means you are losing 10% of power, so to get 60W to the lights, you need to put 65W in.

240V lights = 60W
12V lights = 65W for the same amount of light.

[northernladuk]

HUH?!

How can that be? I was told they use so little electricity you could practically leave them on all the time without worrying about your electricity bill.

I mean that's the whole point of going with 12V bulbs surely (besides the not electrocuting yourself in the bathroom thing).

edit: Or is it that LED bulbs use vastly less than conventional bulbs (e.g. filaments & fluorescent) but there isn't much difference in eleccy usage between LEDs at 12V and LEDs at 240V ?

It's all about the wattage. Ohms law innit.

[OwlHoot]

12V bulbs don't use less leecy than 240V ones. ...

HUH?!

How can that be? I was told they use so little electricity you could practically leave them on all the time without worrying about your electricity bill.

I mean that's the whole point of going with 12V bulbs surely (besides the not electrocuting yourself in the bathroom thing).

edit: Or is it that LED bulbs use vastly less than conventional bulbs (e.g. filaments & fluorescent) but there isn't much difference in eleccy usage between LEDs at 12V and LEDs at 240V ?

[WTFH]

I'm fine fitting a light bulb, provided I have someone to help. I hold the bulb, and they turn me round several times.

Yes, seriously, the 12V LED bulbs with built-in transformers sound like what I need for now, provided they aren't too bulky and heavy.

No - you want 240V LED bulbs, then you don’t need transformers which are inefficient and mean that a 12V LED + Transformer will be less efficient than a 240V LED.

[northernladuk]

I'm fine fitting a light bulb, provided I have someone to help. I hold the bulb, and they turn me round several times.

Yes, seriously, the 12V LED bulbs with built-in transformers sound like what I need for now, provided they aren't too bulky and heavy.

And buzz. I wouldn't be bothering.

[OwlHoot]

The good news is that putting up 12V lights doesn't need the help of an electrician. Unless you're completely incompetent.

I'm fine fitting a light bulb, provided I have someone to help. I hold the bulb, and they turn me round several times.

Yes, seriously, the 12V LED bulbs with built-in transformers sound like what I need for now, provided they aren't too bulky and heavy.