28/10/2025 5:32 am
Topic starter
Notifications
Clear all
0
I have a brushless DC motor taken from an old hard disk drive and I want to power it safely for testing or small DIY applications. Since these motors are usually designed for specific control circuits, I’m not sure about the correct voltage, current, and driving method.
What’s the safest way to power and control a hard drive BLDC motor?
Should I use a dedicated ESC, a custom driver circuit, or a microcontroller-based solution?
Any tips for determining the correct pinout and avoiding damage to the motor would also be helpful.
1 Answer
0
30/10/2025 5:13 am
Use a small sensorless 3‑phase BLDC driver board (made for fans/HDDs) and power it from a current‑limited supply; start at 3–5 V with about 0.5–1 A limit (1–2 A for 3.5″ motors) and only increase if needed—don’t jump straight to 12 V.
An RC sensorless ESC with a servo tester can work but may be difficult; a microcontroller + driver is great for learning but not the easiest.
To find the pinout, measure resistance with a multimeter: with 3 wires, all pairwise readings should match (the three phases); with 4 wires, the pin that reads the same to all others is the neutral; phase order only affects direction, so swap any two leads to reverse.
To avoid damage, never apply DC across two leads, don’t stall the rotor, keep leads short (with a decoupling capacitor near the driver), and watch temperature.
