LED Overheating – Causes and Fixes

High power lighting-class LEDs can run at impressively high temperatures.  But there’s a limit to how much power LEDs can handle and it is essential that adequate heatsinking is provided to prevent overheating. Many LED lighting users are unaware of this so overheating of LEDs can occur all too easily unless prevented by good design!

What causes overheating?

LED overheating can be caused by many rather obvious design factors such as inadequate heat sinking and excess LED power.  But a well-designed LED luminaire can be equally overheated by installing it in an environment for which it was not designed…  So not cooking your LEDs can be as much about getting the design right as properly educating installers and end users.

What damage can overheating cause?

LEDs that overheat will degrade more rapidly in terms of:

• Light output – so called ‘lumen maintenance’.
• Colour change with time

In extreme cases overheating LEDs can result in physical damage to the LEDs themselves, plastic lenses, wires, connectors, printed circuit boards, drive electronics etc.

How can I prevent LEDs overheating?

Here’s a tick list to get you going:

• You’ll need a profound understanding of electronics cooling and a thorough knowledge of the ancillary materials in your luminaire design.
• You need to educate and support customers, especially those new to LED lighting.
• You must observe and follow LED manufacturer’s specifications and seek applications advice in LED cooling.
• Test your products!  Not just in a workshop but in the worst case environment you can think of.  Make sure you measure LED solder point temperatures and make sure you understand the science behind what you are doing.