When an incandescent bulb fails, it's immediately visible why: the filament, quite simply, breaks and the bulb turns off.
LEDs, on the other hand, emit energy as light of varying intensity and color when a current pushes electrons through various materials. So, rather than having binary on-off failures, LED bulbs decay gradually as defects in these materials occur.
Let’s hone in on these potential failure points in more detail.
Within an LED there is an ‘active region’, where a process called radiative recombination occurs and light is produced. If the material used in this active region has an existing defect, it will be worsened by heat and electric current. Eventually, this leads to a decay in the output of the LED Rgb Floodlight.
This issue is avoidable if the manufacturer chooses an LED which will exceed the expected lifespan of other components used within the bulb itself.
In order to maximize the length of time that the LED lights you buy last, check the LED component choice on the bulb’s datasheet to be sure that it’s of a high enough quality.
Electrical Over Stress
"Electrical Over Stress" (EOS) is caused when an LED receives more power than its recommended maximum. This can be caused by human error, faulty power supplies, bad PCB layout or faulty components within the LED bulb assembly.
One cause of EOS is a static discharge making contact with the LED during the manufacturing, shipping or handling of the component. Many manufacturers will protect against this type of EOS by including a static suppressor, which will absorb radio frequencies that would otherwise damage the LED. EOS can also be caused by a power supply spiking and rippling. This can occur through poor design or an inappropriate driver which cannot regulate it's output consistently, leading to a surge in voltage when the LED is turned on. It can also happen during the testing process when LEDs are connected and disconnected rapidly.
EOS can be largely prevented by using protection circuits within the thermal and electrical parts of an LED system. Protection circuits work by regulating the maximum voltage that an LED receives, a bit like a traditional fuse. A protection circuit will kick in once a specific limit is exceeded, and will then reset after the fault clears.
Most well-designed LED systems from major manufacturers include these, with creative solutions like 'soft-start'.
You may have noticed, for example, that some LEDs bulbs take a few moments to turn on. This is designed to reduce the activation spike and increase the lifespan of the LED.
LEDs run much cooler than its competitors but still produce a small amount of heat within their diode. In fact, excessive heat has been found to reduce the lifespan of a LED, making it important to be aware of how LED lights are affected by hot temperatures.
In short, semiconductors and capacitors are both prone to failure under heat stress making it really important to consider the LEDs operating temperature range when shopping for LED lights.
The best performing bulbs are designed to reduce heat stress to protect these heat-sensitive components and increase the lifespan of the bulb. First, non-LED components are mounted separately to the heat-sensitive LEDs. Second, capacitors are designed to operate at higher temperatures.
As electricians, there are two practical tips you can apply to increase the lifespan of LEDs.
If you are installing LEDs, choose appropriately sized luminaires and ensure LED bulbs are ventilated to allow heat to escape.
When purchasing an LED, look at the LED enclosure and heatsink. A well-designed LED bulb should have an effective heatsink with gaps between the fins to allow heat to dissipate into the air.