Author: AETEK

The changes shown here require knowledge in the field of electrical engineering and can overwhelm normal users. Also, I would like to point out possible dangers that exist in certain interventions. All adjustments have been checked for function.

Difficulty: Professional or Electrician (No more warnings. Professionals know when to unplug the mains)

What is this about?
After all the other disturbing noises are much reduced, it bothers me now the noise of the power supply fan.
When changing the power supply, you have to be careful. The PSU built into my A5 is a quality product from Meanwell. The power supply has a short-circuit protection and overtemperature shutdown. These power supplies are also used in industry and are designed for wost case conditions. This means that the cooling is oversized for normal room temperaure (up to about 25 ° C). That's why I decided to reduce the fan speed and thus the noise level. If the cooling does not suffice, then the power supply will switch off in case of overheating. This case could also occur in normal operation when the fan is heavily damaged and then the cooling capacity decreases sharply.

Required Electrical Parts

• 1 x Zener diode 5.1V 1.3W

1. Pull out the A5 mains plug.
2. Remove the cover of the power supply.
3. Install the Zener diode (observe polarity)
4. Check function with a 12V power supply.
5. Reconnect the fan plug in the A5 power supply.
6. Screw the power supply cover back on.
7. Assemble the A5.
8. That's all.

Status: 6. July 2018: Completed