Vacon Vacon 100 Error Code 9

Vacon PLC & VFD Major DC Bus

Model: Vacon 100 | Code: 9

Applicable Systems
Vacon 100

Symptoms

Undervoltage. The DC bus voltage has dropped below the minimum required for drive operation.

Possible Causes

  • Line voltage too low or voltage sag from utility
  • Line contactor or breaker opened while drive is running
  • DC bus capacitor degradation
  • Drive internal power supply fault

Troubleshooting Steps

  1. Step 1: Check the equipment status and fault indicators to confirm the active fault code
    Fault indicator or HMI displays code 9 as active
  2. Step 2: Verify all electrical connections, wiring harnesses, and connector seating
    All connections secure, no corrosion, loose pins, or damaged wires
  3. Step 3: Check the communication cable continuity and connector seating at both ends
    Cable continuity confirmed, connectors fully seated with locking tabs engaged
  4. Step 4: Verify communication parameters (baud rate, node address, protocol) match network configuration
    All communication parameters match the network setup
  5. Step 5: Inspect cable for EMI interference: check routing away from high-voltage lines and motor cables
    Cable routed away from EMI sources, shielding intact
  6. Step 6: Check terminating resistors at bus endpoints if applicable (e.g., PROFIBUS, CANopen)
    Terminating resistors installed at both bus ends
  7. Step 7: Reset the fault after restoring communication: power-cycle the affected node
    Communication restores and fault clears

How to Reset

To reset: 1) Fix the communication cable or parameter issue. 2) Power-cycle the affected node. 3) Verify communication restores. Caution: Check all nodes on the bus.

Frequently Asked Questions

  • Q: What does fault code 9 mean on the Vacon Vacon 100?

    Fault 9 indicates a communication fault. The equipment has lost communication with a connected device or network. Check the communication cables, connectors, and network parameters.

  • Q: Can I continue operating the equipment with fault 9 active?

    No. The equipment has detected a fault condition and has taken protective action (typically stopping or derating). Continuing to operate without fixing the root cause may cause further damage. Always investigate and fix the fault before resuming operation.

Related Vacon Fault Codes

Source: Vacon 100/100X Drive User Manual, Danfoss/Vacon Documentation

Category: PLC & VFD