energy saving 12 volt or 230 volt downlighters?

[murdock]

i have a request from a customer to remove all his 12 volt downlighters and install 230 volt downlighters...because he wants to save electricity.

unless i am missing something a 50 watt lamp whether it is 12 volt with a transfomer or 230 volt draws the same amount of power...i dont see how you can save money...what he will find is the 230 volt lamps pop a lot faste rthan the 12volt ones do...so in the long run he will be paying more replacing lamps than he will just sticking to the 12 volts ones...provided the installation was done correctly...using the correct size wires.

w=vxi

whether you use a 50 va transfomer or a 50 watt lamp it draws about the same amount of power.

now if he was considering replacing with led lights then i could understand...the led lights are becoming more efficient and if you buy good quality ones will also give you a much better lux reading when do your lux report once all the lamps have been replaced...because a 3 or 7 watt led lamp draws a lot less than a 50 watt.

[murdock]

the next question...which led from your experinces using them are the best to install for customers...the multiple 3 watt...the 3 led unit...phillips...osram?

[Mike Simmonds]

Another thing to consider is that the 230 volt globes are more expensive than the 12 volt ones. I really do not understand his rationale for wanting to change from 12 volt to 230 volt!

[Justloadit]

Hy, I have learn't, do not argue with the customer, do what he wants, collect your bucks and move on.

Be aware of LED lights, the 3 LED jobies from Ellies, consume 4 Watts, but only give you 150 Lumen's, much to be desired.

I am using some top of the range CREE LEDs, which give you 122 Lumens per watt for the cool white, but unfortunately they are not available for the down lighters. The manufacturing just makes the price almost double of the crap currently available, and with our uninformed folk, who never buy the expensive good stuff, which effectively places good quality manufacturers out of business.

I just currently started to manufacture a 3Watt 10.5 to 30V DC security light, which gives over 300 Lumen's of light. See my brochure. Will post more soon on the forum.
3Watt Security Light.pdf

[murdock]

i have just installed 1 x warm white...1 x cool white...and left the 1 x 50 12 volt lamp...then took some lux readings...

12 volt lamp ...380 lux
warm white led...110 lux
cool white led...100 lux

it looks like the cool white led lamp is the brightest...when you stand and look down the passage...yet it had the lowest lux reading...all measured at the same height...1 metre ffl

[murdock]

cost for the light fitting complete with 230 volt power supply?

[Justloadit]

Hi Murdock,

Be wary of the light meter that you are using. The LED is a very narrow light spectrum, usually referred to the temperature, cool white is around 5000K and warm white between 3 and 4000K. So it is quite possible that the readings may be slightly lower due to the meter sensitivity looking for a larger light spectrum.

Usually the cool white LEDs have more lux output, but it also be due to the manufacturer of the LEDs.
Note that the LEDs will never match the lux output of the incandescent, simply because the incandescent runs at about 180 degrees C, while LEDs can not run higher than 70 degrees of life span is drastically reduced. Until efficiencies improve, this will be the issue. At the moment CRE does about 122Lux per Watt, which currently is the most efficient, but put 3 of them in a small housing, and you can understand the problem to dissipate the heat, and ensure that the LEDs do not go over 70Degrees.

[IMHO]

Here is something I have done. ACDC sell these energy saving 20w lights as a replacement globe for the 500 watt halogen floodlights. I build one of them into the light fixture at our reception, as the globes fuse like every week. It had those ES 40watt x 2 fittings that I just hate. I replaced the 2 x 40 watt with this 1 x 20 watt and I have 3.5 times the lumen ! I measured the power consumption with my amp meter and it says it is using 0.08 amps. That is more like 18 watt. My wife is thrilled with the abundance of light, which she never had, and I do not get called every now and then to come replace the globes. The lifetime of this, 18 hours a day, should be like 3 years if the manufacturer can be believed. I build one into my fish tank over a year ago and it is still going, moisture and all! BTW, the temp is 6500k.

Any case, here is what I did.