14/08/2026
How to wire a variable frequency drive
Correct VFD wiring is critical for safe operation and to avoid equipment damage.
Always cut off power and wait for internal capacitors to fully discharge before starting any wiring work.
Basic wiring overview:
🔌 Power Input: Connect mains supply to R/L1, S/L2, T/L3 terminals
🔌 Motor Output: Connect the 3-phase motor to U, V, W terminals
⚠️ Never connect mains power to U/V/W, this will destroy the drive!
🔩 Reliable grounding for VFD cabinet and motor frame
🔘 Control wiring: Start/stop, speed potentiometer or PLC signal terminals
Key wiring best practices:
✅ Separate power cables and low-voltage signal cables to reduce EMI interference
✅ Use shielded cables for long-distance motor wiring
✅ Check all terminals for tightness to prevent overheating
✅ Always follow the official wiring diagram of your VFD model
What are the most common wiring mistakes you have seen on site? Share your experience below.