How to Avoid Heat-Related, Premature Failure of your Industrial LED Lighting.


Fact-based analytics are essential to LED lighting project success.


As you know, most lighting salespeople are more interested in landing a sale than doing what’s best for you and your company. The best way to protect yourself against getting stuck with inferior LED lighting is to be armed with the right information.

In our first installment, Is your LED lighting project headed for failure, we looked at how susceptible the light engine can be to heat-related failure. Next, Will your LED lighting AC/DC power supplies (LED Driver) survive the real world, focused on heat-related failure of the drivers. Now, let’s turn our attention to the data you want to have on hand before you finalize a purchase decision.

Specifications from overseas manufacturers can be suspect. Therefore, it pays to do a little investigating into the temperature ratings of any LED fixtures you are considering purchasing.


Run the numbers for yourself.

Tools needed:

  • Temperature gun
  • LED light to be tested and access to the driver
  • Temperature data logger – HOBO is one manufacturer but there are many out there

There are two ways you can calculate the rated temperature of the fixture for yourself.  The driver is the weakest link, so the driver rated temperature determines the rated temperature of the fixture unless the driver can be mounted independent of the fixture in a cooler environment. In cases where the driver can be remotely mounted, the testing procedure is handled a little differently.


Calculating internally mounted driver temperature ratings.

First, let’s look at the testing procedure for internally mounted driver fixtures. Turn the LED light on, let it operate for 3 hours so it gets to full temperature.  Set the temperature gun to Celsius and aim it at the driver. Record the temperature. Also, record the room temperature in the vicinity where the light is located, basically at ceiling height.

The calculation is simple: Take the rated driver temperature minus the driver running temperature you recorded. Then, add the room temperature you recorded and that will give you the true rated temperature of the driver.

The example shown below demonstrates the process you would use to calculate the driver temperature. Rated temperature of an internally mounted driver is typically around 50° Celsius.


Calculating temperature ratings for fixtures with remotely mounted drivers.

If the LED driver is remote mounted via cable – the light engine can be mounted in a higher heat environment than the driver. In these cases, use the following procedure to calculate the temperature rating.

On the temperature gun, set to Celsius, take a temperature reading of the LED board and record it. To do so, aim the temperature gun at the top side of the fixture, directly above where the LEDs are located. Also, record the room temperature in the vicinity of the light fixture. Once again, basically at ceiling height.

In this case, start with the rated temperature of the LED chips (105° Celsius is typical) minus the temperature recorded of the LED board. Then, add the room temperature recorded.


Once you have your calculations, compare your findings to what’s listed on the manufacturer’s spec sheet. If the numbers don’t match-up, that manufacturer probably isn’t the company you want to do business with.


Understand your operating environment.

You don’t have to be a foundry or other high-heat environment to be concerned with the potential for heat-related fixture failure. Poorly designed light engines and drivers easily can fail in room temperature environments. Why? Heat rises. So, when you are recording room temperature readings, it’s critically important that you take the reading at the level where the lights will be installed – either at or near the ceiling.

Use data logging devices to get accurate readings. It’s best to leave the devices in place for two weeks to a month, in order to account for possible temperature fluctuations due to time of day, changes in production schedules and peak operating demand. Having this data will give you a much clearer picture of the actual fixture temperature ratings required to adequately and reliably meet your lighting needs.



Wasmer can help.

If you lack the time and/or skilled resources needed to get the information you want regarding fixture ratings, building temperatures, etc., we can help. Contact us today or visit For more information about all of the factors that should be taken into account to ensure the success of your LED lighting project, be sure to learn more with our Proven Effective Process white paper. Remember, with the right partner, an LED lighting project can do a lot more for your business than reduce your energy consumption. It can improve safety, productivity, morale, overall product quality and more. We just want to make sure you make the most of it.




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