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track lights-12V or line voltage...same watts /same comsumption?

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electrojuapiño

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I just installed a track here at home expecting it to be brighter and really nice looking but so far I had to mount 3 fixtures with 50W halogen bulbs to get decent light! I was hoping that it was going to be about the same wattage as the old 60W incandescent bulb I had before to get the same amount of light in the room. Now I discover that I need almost 3 times more "power" to have about the same light output (I mean how much the room is lit now...the brightness)

In the store they say not to worry that this fixtures I have put up are 12V so it consumes a lot less electricity than the equivalent same wattage incandescent bulb or if they where line voltage and not 12V fixtures. Is this true? I see that now I will use 150W total so it's a lot more electricity expen$e (3x50w fixtures) to get the same brightness.

Of these two bulbs: a 50W/12V (low voltage) halogen bulb and a line voltage 50W halogen bulb.....what regular incandescent bulb wattage are they equivalent to in terms of electricity comsumption..... for example: "a 50w/12v halogen bulb comsumes the same electricity as a 50 watt incandescent bulb." If anyone understands and is kind enough to explain to me in a simple comparison like this then I would understand.

I need to put more lights and need to know if it's worth it! Thanks a million!:)
 
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kchriste

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In the store they say not to worry that this fixtures I have put up are 12V so they consume a lot less electricity than the 60W incandescent bulb or if they where line voltage and not 12V fixtures. Is this true?
NO. This is NOT true.
for example: "a 50w/12v halogen bulb comsumes the same electricity as a 50 watt incandescent bulb."
This is true.
Actually a system of three 50W, 12V bulbs, with the required transformer, consume a more than 150W because of the losses in the transformer. Noticed that the transformer gets hot? That is wasted power. In fact, most of those cheap transformers are really inefficient because they cheap out on the core size, get hot, and can be a fire hazard. Worse is some halogen lights which put the switch for the lights on the 12V side so the transformer idles all the time even when the lights are out.

As for the math:
A 50W 12V bulb requires 4.17Amps at 12V (4.17 x 12 = 50Watts) but a 50W 120V bulb requires 0.417Amps at 120V. (0.417 x 120 = 50Watts)
 
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electrojuapiño

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ok....but because its 12v and not line voltage (110 AC) does it mean that the actual electricity needed is less to make this power?...comparing to a incandescent bulb of the same wattage? that's the part that confuses me because 12v seems like a small amount is needed

what's the point of making the fixtures using a transformer etc and changing it to 12v if it winds up comsuming the same house current as a line voltage fixture of the same wattage? Why do they sell these then? aaaaargh! :-(
 
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electrojuapiño

New Member
A 50W 12V bulb requires 4.17Amps at 12V (4.17 x 12 = 50Watts) but a 50W 120V bulb requires 0.417Amps at 120V. (0.417 x 120 = 50Watts)



I'm still stuck with this math for although I see that something that requires 4.17 amps to work uses more electricity than something requiring only 0.417 amps.......but one is 12v and the other is 120v.......are you simply saying that they BOTH add up to the same electricity compsumtion then? The electric bill is going to be the same no matter which you use?

Please forgive my being a knucklehead when it comes to electricity/electronics!!!!!!!!!
 

audioguru

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I think you need three 50W halogen bulbs to replace one 60W incandescent bulb because they are focussed at the floor but the incandescent bulb lighted the entire room in all directions.
 

kchriste

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what's the point of making the fixtures using a transformer etc and changing it to 12v if it winds up comsuming the same house current as a line voltage fixture of the same wattage? Why do they sell these then? aaaaargh! :-(
One reason is so that they can make the bulbs much smaller. Another is so they can use the "track" as the electrical conductors, because you can't be shocked by 12V.

are you simply saying that they BOTH add up to the same electricity compsumtion then? The electric bill is going to be the same no matter which you use?
That's exactly what I'm saying.
 
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RadioRon

Well-Known Member
The reason for 12V Halogen is historical. When halogens first came out, they were only producing low voltage ones at any reasonable price. MR16 and those little peanut bulbs were around but you couldn't get higher voltage ones. So, lots of companies made track lights to use the MR16 bulbs because Halogen lamps were so much better than regular tungsten, with better colour, and more light for given watts. So, even with the damn transformer they were great lights, especially for store displays and highlighting things. Anyway, later on they figured out how to make higher voltage versions at reasonable cost and so you could buy PAR lights to fit larger flood fixtures but even today these Halogen PAR lamps are relatively expensive. Finally in the last few years we've seen GU10 halogen bulbs come along, which ironically are the same shape and size as the old MR16, but they take 120V directly. Now, when we shop down at the Home Depot store, most of the track lights use GU10 bulbs and no more transformer.

The transformer approach isn't so horrible since the majority of the "transformer" types don't use big magnetic transformers, they use switching type voltage converters which are more efficient and smaller. So the losses are not too bad (its all relative I guess). Transformer types suffer more by being relatively clunky looking compared to the latest 120V heads. Oh, and transformer types need special dimmers if you want to dim them, whereas the 120V GU10 bulbs do not.
 

electrojuapiño

New Member
yes audioguru that I do realize and expected....the problem is that I was assured that using 3 halogens of 12v and 50w each was not a problem in terms of wasting more electricity because according to the store " they comsume a LOT less electricity" than my old incandescent bulb because these are "low voltage of only 12 volts"
All I want to comfirm if anyone understands about it is that if I have, for example, a 100 watt 12 volt halogen bulb - does it make my electric meter go any faster than an also 100 watt incandescent bulb? thanks:eek:
 

RadioRon

Well-Known Member
That's exactly what I'm saying.
To add to what kchriste is saying...we measure electricity as power, not just voltage or current alone. Look at it this way. Let's say you are using one of those tracks where the voltage in the track is 120V and the lamp fixture has a built-in transformer that changes the voltage down to 12V for the MR16 bulb. What do you care if the transformer swaps current for voltage and voltage for current, as long as it does so with little or no waste. It still looks like a 120V light from your point of view. Heck, as long as you deliver 120V to the fixture, they could transform that down to 0.1 volts and push 500 amps through the bulb for all I care as long as they do it efficiently. Its still just 50 watts and that's what your paying for, watts.


edit: oops looks like I was typing too slow and you guys finished allready. oh well
 
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electrojuapiño

New Member
yes it's clear now radioron! thanks everyone!

by the way....I now hate 12v fixtures!... and track lights in general for that matter! Going to return everything and get a nice lamp with either incandescents or even compact flourescents inside grrrrrrrrrrrrrrr :p
 

RadioRon

Well-Known Member
Oh, I really like those little halogen spotlights, but I must agree that they don't replace ambient light fixtures. You need something in the middle of the room, or some lamps on tables to fill in the ambient stuff. Halogen spots are just for highlighting walls and the center of a table and so on. You need both types to make it great.

Oh, and I bet you end up hating compact flourescents too. The colour is just not very good, and the higher wattage ones take too long to warm up, and the dimmable ones are scarce and way too expensive, and they don't always fit the fixture, and they don't look as pretty as some filament bulbs, and and and, well you get the idea.
 
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Torben

Well-Known Member
Here in Ontario Canada they're phasing out standard Incandescent bulbs.
They're planning on that here in B.C. too, AFAIK. Drives me crazy. The build quality on many of the ones we've got has been hit or miss, with some lasting only weeks before biting the bullet. The amount of materials which goes into making just one of these turkeys is ridiculous, and the light is unpleasant. Then there's the matter of disposal.

It wouldn't be quite so bad if a home were pre-wired with ballasts so the bulky active base wasn't required, but I'm not aware of any way to just get the bulb portion (without taking them apart) so that's a non-starter.

I use them in places where long burn time is the dominant factor, but where quality of light is more important I prefer incandescents or halogens.


Torben
 
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