eunice123

This video explains some lighting terms

The following was posted by a forum member in another post on the same subject: Tried reading up as well as re-looking at the posts here. If I understand it correctly, looks like different lights for different purposes. Lumens measures total light output (ie, measured at the light source). Lux (which is lumens per sq metre) measures illuminance (ie, measures light at the object being lighted up). So the lumens of a lamp is a fixed number. But the further you move away from it, the lower the lux number will drop because the area covered by the light increases. Their lamp produces 750lm with 12W, giving 62.5lm/W. This is pretty decent efficiency for LED, as far as I know. Yours produces 700lm with 9W, giving close to 78lm/W. Pretty impressive, assuming it's not being overdriven. Assuming that all the figures above are accurate, your lamp is more efficient but produces less light - 6% to 7% less. But when you start measuring how objects are being lighted up, we need to look at lux. So, if at 1m, they measure 200 lux, that's taking into account the beam angle - ie, the 750lm is spread out over the area covered by the beam angle (120 degrees, which is pretty broad). If, at 1.2m, your lamp measures 700lux (you stated 700lm in your post, but I presume you meant lux, because lm measures light output at source, so distance is not a factor), it probably means that your beam angle is much narrower than theirs. Likely different lamps for different uses. A large beam angle for general lighting (like ceiling downlights) and a narrow angle for accent lighting (eg, lighting up artwork) That's my understanding anyway. Still learning.

Great - At last some kind wise soul step up with unbiased and accurate explanation. Also have to take into acccount, product warranty when purchasing LEDs

You seem to confuse lux with lumens. If you look at the detailed spec from the link provided, it says 750 lumens for cool white. It gives out 200 lux brightness at 1m. There are many considerations when purchasing LED products, such as the brand of the LED chip used, the driver, etc... More than 1000 pcs of the round LED downlights have been installed in various homes in singapore, with only 2 failure which are replaced by the company as the products carry 2 years warranty. The company does not need to defend itself as its track record of customers speak for itself.

I think the fastest way to source for LED is to do your market reseach by doing a google seacrh. Ask the shops all the questions you need, and then go down and view the products. This will help save precious time and energy

Some of my friends are currently using LED downlights from VTX Solutions. Very slim and even light output. Can call up 96526095 to find out more