Service Man Diary - Decreased Brightness in the PARZ1003K

Hello everyone,
Today, I will be repairing the American DJ PARZ1003K, which was brought in due to a brightness drop.

American DJ / PAR Z100 3K LED Par Light

The American DJ PAR Z100 3K is an LED par light equipped with a 100W COB LED. The housing design is similar to a halogen bulb par light, ensuring it can be used without any issues. It’s recommended for illuminating stages in theater productions and live events.

Let’s get started.

Let’s see how it operates.

When tested in manual mode at full output, as indicated, the light is quite dim.
It barely glows, which means it’s not functioning effectively as a par light.

Having confirmed the issue, I proceeded to disassemble the internal mechanism. The internal components are compact and neatly wired, making it easy to handle.

Since the power is on and the LED is at least faintly lighting up, I focused my attention on the lens at the front.

Removing the lens reveals...

An LED that looks like a fried egg.

Upon closer inspection, it seems the LED chip is indeed burnt.

The faint glow was likely due to the small remaining unburnt portion of the LED.

The cause of this could be deterioration over time or excessive heat. However, in this case, the culprit is the degradation of the thermal grease.

When I removed the LED, the thermal grease had turned black and flaky.

Thermal grease, which should efficiently transfer heat, was instead trapping it, causing the LED to burn out.

For more information on the role of thermal grease, please refer to my previous blog post:
⇒ What are Thermal Grease and Heat Sinks?

Looking at the heatsink with the LED and lens removed, you can clearly see how much heat the LED generates.
Conversely, it also highlights the importance of having a heatsink that can dissipate such heat effectively.

Next, I replaced the old LED with a new one and performed a preliminary operation check.

There were no issues with other parts, and the problem was resolved successfully.

Finally, I reassembled all the parts into the housing to complete the repair.

Thumbs up to the PARZ1003K, which will keep shining brightly tomorrow.

As we head into the hot season, please ensure the light is used in a well-ventilated environment to prevent heat buildup.

Thank you for reading.

See you next time.