Lumen converting WATTS

Lumen (lm) is a measure of luminous flux. The lumen value indicates the amount of light a lamp emits. The term lumen stems from Latin and means light.

“Lumen is the determining value for the brightness of a lamp.”

Anyone still looking at watts when deciding on buying a luminaire will be left in the dark. The one measurement that counts in modern LED lighting technology is the lumen – a unit of measurement that is a much better indication of the brightness off a lamp than wattage.

 
How to convert watts into lumen

If you are having difficulties getting away from the more familiar wattage values, you can easily convert watts into lumen. So ... how do I go about stepping out of the dark and into the light? Here is an easy rule of thumb to follow:

Conventional wattage x 10 = lumen value

Lumen is a more precise measurement for the brightness of a lamp than wattage.
LED lamps consume at least 80% less power than conventional incandescent light bulbs. They meet the requirements of efficiency classes A, A+ or A++.

What is the difference between omnidirectional lamps and reflectors?
The lumen value (lm) indicates the luminous flux or the total amount of light given off by a lamp, whether it is an omnidirectional lamp (bulb shaped) or a reflector lamp.

The brightness of omnidirectional lamps and reflectors is calculated on a different basis.


Lumen in omnidirectional lamps

The unit of measure lumen (lm) specifies the total amount of light that an omnidirectional lamp emits in terms of luminous flux.






Lumen in reflector lamps

1. All reflector lamps with a beam angle of up to 90° have a brightness specification in terms of "luminous flux in a 90° angle". This specification can be used to compare lamps in this beam angle class. Brightness is measured within the 90° angle, even if the actual beam angle is smaller.

2. All reflector lamps with a beam angle of 91° to 120° have a brightness specification in terms of "luminous flux in a 120° angle". These lamps are not suitable for accent lighting.

3. Lamps with less than 80% of their total luminous flux within a beam angle of  120° are categorised as "non-directional light" or "general diffuse lamps" The complete 360° circumference of the lamp is used to calculate the luminous flux (lumen, l,) of this type of lamp.