Saturday, April 12, 2008

Choosing the type of downlight

For the lighting solution to various places in my house with plaster ceiling, I have chosen to use the 6" cone stainless steel finished reflector housing with PL-C (square base) vertical mounting lampholder base and round open stainless steel trim, using 18 watt energy saving compact fluorescent 2-pins PL-C lamp that emits warm yellowish light.

Here is how it looks like:

The reasons being as follow:

6" downlight - downlight with bigger aperture is brighter. 6" is just nice and 8" will looks too large unless the ceiling is very high. By using 6", less downlights are required to light up the area. My living room just has 4 downlights only, located at each corner of the ceiling.

Stainless steel housing and trim - unlike chrome or other finishing, it will not rust or discoloured.

Vertical mounting position - convenient position easier to install and remove the lamp.

Round shape trim - cost is cheaper than square trim. Also, square trim are normally covered with glass.

Open trim - light is brigher than covered with glass lens. Also, small insects might be trapped inside the downlight with glass lens, and later the downlight will be filled by their dead bodies. Replacing the lamp inside requires to remove the glass lens too.

18 watt energy saving compact fluorescent lamp - 18 watt is just nice for the required brightness. Energy saving compact fluorescent saves 80% of electricity from incandescent bulb with same brightness.

PL-C lamp - easier to install (just push in) and remove (just pull out). It works with ballast that enable its lifespan to be twice as longer than the exposed spiral or U shaped counterparts.

Warm yellowish light - actually its brightness is the same as white light, but we have less glare and better eye comfort with warm yellowish light. It is suitable for long time reading too.

This kind of downlight can be installed with emergency option unit, whereby a small rechargeable battery is hiding on top of the ceiling and connected to the light. In case of electricity blackout, the downlights can still be switched on for a few hours by using the backup power supply from the emergency option unit.


Johnny 5 said... Reply To This Comment

As someone who sells light bulbs for a living, I am less enthusiastic than most about compact fluorescent bulbs. This is due to the fact that the ones currently available contain significant amounts of mercury. If one of these bulbs should break inside of a person’s home, it could cause a challenging disposal situation. It is my belief that the technology should progress to a point at which the mercury levels are low or nonexistent before people changeover their entire homes. Another consideration is that as these bulbs burn out, they will most likely be thrown away as though they are normal rubbish and landfills will have incredibly high levels of mercury in their soil as a result.

Voyager8 said... Reply To This Comment

I believe LED technology will make the light blub of tomorrow, which is even more environment friendly and energy saving.

Unknown said... Reply To This Comment

Most CFLs today on the market contain less than 5mgs of mercury and there are CFL options out there that contain as little as 1.5mgs of mercury- which can hardly be called a “significant amounts of mercury” considering that many item in your home contain 100s of times more of mercury including your computer. Mercury levels in CFLs can never be “nonexistent” since mercury is a necessary component of a CFL and there is no other known element that is capable of replacing it. But CFLs actually prevent more mercury from entering the environment. According to the Union of Concerned Scientist, “a coal-fired power plant will emit about four times more mercury to keep an incandescent bulb glowing, compared with a CFL of the same light output”.

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