AI Video Summary: How to wire PC fan to wall wart power supply
Channel: Jacob Dykstra
TL;DR
This tutorial demonstrates how to power 12-volt PC fans using a standard wall wart power adapter instead of a full computer power supply. The video covers identifying voltage requirements, stripping and connecting wires, determining polarity, and safely soldering the connection to run the fans.
Key Points
- — The host explains that a full computer PSU is unnecessary for powering small 12V DC fans and that a simple wall wart adapter is sufficient.
- — Analysis of fan specifications shows they typically require 12V DC and very low current (around 0.16 amps), which a standard 1-amp wall adapter can easily handle.
- — The process begins by cutting the barrel jack off the wall adapter and stripping the two internal wires to expose the positive and ground lines.
- — The host advises using a multimeter to determine wire polarity, noting that reversing the connection usually won't damage the fan but will prevent it from spinning.
- — Wires are connected by twisting them together, with the recommendation to solder the joint and apply heat shrink tubing for a secure and insulated connection.
- — The video notes that using a lower voltage supply (e.g., 9V) will cause the fan to spin slower and quieter, while matching voltages ensures full speed.
- — The final demonstration shows the fan successfully spinning after being connected to the wall adapter, proving the method works without a computer PSU.
Detailed Summary
The video begins with the host, Jacob Dykstra, addressing a forum question about how to power 12-volt DC fans salvaged from an old server without using a full computer power supply unit (PSU). He explains that while computer PSUs provide high amperage, they are overkill for small fans. Instead, he recommends using a standard 'wall wart' AC/DC adapter, which is much lighter and more convenient. He distinguishes between switching power supplies (lightweight) and magnetic transformers (heavy), noting that either type works fine for this application as fans do not require precise voltage regulation. Next, the host analyzes the specifications of the fans and the power adapter. He shows that a typical fan requires 12 volts and draws very little current, often around 0.16 amps. A standard wall adapter providing 12 volts at 1 amp is more than sufficient to power multiple fans simultaneously. He explains the wiring on the fans, noting that the red and black wires are for power (positive and negative), while a yellow wire, if present, is for RPM monitoring and is not needed for basic operation. The goal is to match the 12-volt output of the adapter to the 12-volt requirement of the fan. The practical demonstration involves modifying the wall adapter by cutting off the barrel jack to expose the internal wires. The host strips the insulation from both the adapter wires and the fan wires. He discusses how to identify polarity, suggesting the use of a multimeter to check for positive and negative voltage, though he notes that simply trying the connection is often safe because reversing the polarity on a DC fan usually just stops it from spinning rather than destroying it. He then proceeds to connect the wires, recommending soldering them for a permanent fix and covering the joint with heat shrink tubing for insulation and safety. He also mentions that connecting multiple fans in parallel is possible. Finally, the video concludes with the successful testing of the setup. The fan spins up immediately upon plugging in the adapter, confirming the connection is correct. The host adds a tip that using a lower voltage adapter (like 9V or 6V) will cause the fan to spin slower and run quieter, which might be desirable for noise reduction. He emphasizes that this simple DIY solution is far more practical than repurposing a large computer power supply for such a small task.
Tags: electronics, pc fans, diy, power supply, tutorial, wiring, 12v