March 5, 2019 at 20:02LED lamp durability and reduced light output
I conducted an experiment and compared how the luminous flux of different LED lamps decreases for forty minutes after turning on.
Before any testing, I will definitely warm up the LED lamps for at least 30 minutes. The fact is that any LED lamp during this time reduces its luminous flux as the LEDs and electronics warm up.
Using a homemade Lamptest-1 black box, I measured how the luminous flux of twelve different LED lamps changes in the first forty minutes after turning it on. For clarity, he selected nine of them:
IKEA Ryet 603.979.60 LED1741G6 ;
OSRAM LEDSCLA60 10W / 827 230VFR E27 ;
ASD LED-A60-std 7W E27 3000K 630Lm ASD ;
Camelion LED ULTRA LED6-A60-FL / 830 / E27 filament;
Lisma SDF-6 A50 filament;
Toshiba 00101315012B ;
Geniled 01327;
Gauss 102802115 Graphene filament;
Saffit SBA6010 55004 .
Here is what happened.
The first thing that catches your eye is a significantly larger drop in brightness (hereinafter I will use this word, not as a technical term, but as a everyday concept) in a Saffit lamp. After 25 minutes, the luminous flux of this lamp fell to almost 70% of the initial one. I note that this is a very, very bad bulb (stated 10 W, in fact 5 W, stated CRI 80, in fact 72, the light flux has not yet been measured, but I think it is also in the region of half the declared). Such a drop indicates that most likely the LEDs are operating in overload mode. Such a bulb will not work for a long time.
The second interesting point is the difference in the graphs of the three filament lamps. They heat up faster and stabilize faster. At the Camelion lamp, the luminous flux stabilized within five minutes after switching on and after that within 35 minutes it fell by only 1%.
An interesting graph is the old OSRAM lamp with a heavy radiator (the lamp weighs as much as 117 grams). It heats up so slowly that even 40 minutes was not enough to completely stabilize the light flux.
The wavy graph of IKEA Ryet is caused by a ripple of light (its ripple coefficient is about 13%).
Perhaps by the degree of decrease in luminous flux it is possible to predict the lamp life and if in 15 minutes the brightness has fallen by more than 20%, the likelihood of premature lamp failure is quite high.
So far, I don’t have the opportunity to test each lamp this way, but if I make a special firmware for Lamptest-1 and make the devices themselves a few pieces, the process can be automated to stream.
© 2019, Alexey Nadezhin
Before any testing, I will definitely warm up the LED lamps for at least 30 minutes. The fact is that any LED lamp during this time reduces its luminous flux as the LEDs and electronics warm up.
Using a homemade Lamptest-1 black box, I measured how the luminous flux of twelve different LED lamps changes in the first forty minutes after turning it on. For clarity, he selected nine of them:
IKEA Ryet 603.979.60 LED1741G6 ;
OSRAM LEDSCLA60 10W / 827 230VFR E27 ;
ASD LED-A60-std 7W E27 3000K 630Lm ASD ;
Camelion LED ULTRA LED6-A60-FL / 830 / E27 filament;
Lisma SDF-6 A50 filament;
Toshiba 00101315012B ;
Geniled 01327;
Gauss 102802115 Graphene filament;
Saffit SBA6010 55004 .
Here is what happened.
The first thing that catches your eye is a significantly larger drop in brightness (hereinafter I will use this word, not as a technical term, but as a everyday concept) in a Saffit lamp. After 25 minutes, the luminous flux of this lamp fell to almost 70% of the initial one. I note that this is a very, very bad bulb (stated 10 W, in fact 5 W, stated CRI 80, in fact 72, the light flux has not yet been measured, but I think it is also in the region of half the declared). Such a drop indicates that most likely the LEDs are operating in overload mode. Such a bulb will not work for a long time.
The second interesting point is the difference in the graphs of the three filament lamps. They heat up faster and stabilize faster. At the Camelion lamp, the luminous flux stabilized within five minutes after switching on and after that within 35 minutes it fell by only 1%.
An interesting graph is the old OSRAM lamp with a heavy radiator (the lamp weighs as much as 117 grams). It heats up so slowly that even 40 minutes was not enough to completely stabilize the light flux.
The wavy graph of IKEA Ryet is caused by a ripple of light (its ripple coefficient is about 13%).
Perhaps by the degree of decrease in luminous flux it is possible to predict the lamp life and if in 15 minutes the brightness has fallen by more than 20%, the likelihood of premature lamp failure is quite high.
So far, I don’t have the opportunity to test each lamp this way, but if I make a special firmware for Lamptest-1 and make the devices themselves a few pieces, the process can be automated to stream.
© 2019, Alexey Nadezhin