DC link undervoltage

What does 3220 mean?

The DC link voltage within the drive has dropped below its minimum operational threshold. This is typically caused by a loss or dip in the incoming AC supply voltage or an issue with the drive's internal power supply rectification. Continued operation with undervoltage can lead to unstable motor control or drive malfunction.

• Momentary or sustained sag in incoming AC supply voltage (e.g., below 340V AC for a 400V AC system).
• Blown input fuses or tripped circuit breaker in the drive's supply line.
• Loose or corroded connection at drive input terminals L1, L2, L3, causing high resistance and voltage drop.
• Internal pre-charge circuit failure within the drive, preventing proper DC link charging at power-up.
• Incorrect input voltage parameter (e.g., P99.02) set lower than the actual supply voltage, causing premature undervoltage tripping.

Click steps to track your progress.

1. 1

   1. Measure incoming AC supply voltage at drive input terminals L1, L2, L3. Verify it is stable and within the drive's specified operating range (e.g., 380V-480V AC).

2. 2

   2. Inspect input fuses and circuit breaker in the main power distribution panel for the drive. Replace blown fuses or reset the breaker.

3. 3

   3. Verify tightness and condition of wiring connections at drive input terminals L1, L2, L3 and at the upstream contactor or breaker.

4. 4

   4. Monitor the DC link voltage (e.g., parameter P01.07 or display) during power-up and operation to observe the voltage level and any drops.

5. 5

   5. Check for correct setting of input voltage parameter P99.02 (Rated Input Voltage) to ensure it matches the actual AC supply voltage.