Firstly, let’s summarize some of the concepts on Led lighting:
First, Luminous flux (unit: lm), refers to the human eye can feel the radiant power.
Second, Degree standard value (unit: lm/m2), normal family according to demand reference value 100 ~ 300 lm/m2.
Third, Watts (unit: w), power.
Forth, Luminous efficiency (unit: lm/w), the efficiency of electrical energy into light energy, the general efficiency of LED light is 90 ~ 130lm/w. For example, for a 20W bulb, the light efficiency is 100lm/w. Then the luminous flux is 20W*100lm/w=2000lm.
Fifth, it depends on the function of space. For example, the general activity is 100LM/m2 while writing and reading requires 300LM/m2. But in the case of placing a desk in the bedroom, if it is loaded with a main led lighting, it will be too bright when it comes to general activities. At this time, you can use “mixed”, that is, install a table lamp or other auxiliary led lighting.
Sixth, the room is dark or not? In the case of multiple lamps, the luminous flux is generally additive. For example, a 10m2 room requires 1000~3000LM flux. The lumen flux of a downlight is 200 lm, so we can install 5 to 15 inch downlight evenly in space.
Of course, under actual conditions, a 10-m2 space is unlikely to hold so many downlights. At this time, a 200-millimeter desk lamp can be installed separately in the corner of the desk. The desk needs a bright range of about 1m2, which is enough. However, under actual circumstances, it is impossible to read and write the entire room. It is only a small corner. Therefore, 10 square meters of room usually install about 10W LED main lights, and then see the writing area, and then with a separate lamp.