EL
ErrorLib
Brands
||
  1. Home
  2. Vacon
  3. 20 Compact
  4. 9
About·Privacy·Terms

ErrorLib — Industrial Fault Code Library

Disclaimer: ErrorLib is an independent technical reference tool. While we aim for accuracy, always verify with the manufacturer’s official service manuals before performing maintenance on industrial equipment. ErrorLib is not affiliated with the brands listed.

9

Under voltage

Vacon · 20 Compact

What does 9 mean?

The DC-link voltage has dropped below the internal safety limit of the frequency converter. The most common causes include a supply voltage that is too low, or a power outage. In some cases, it could also indicate an internal fault within the frequency converter.

Common Causes

  • Input voltage below minimum threshold (e.g., P1-01 < P1-02).
  • Loss of one or more input phases.
  • Faulty main power supply unit.
  • Brownout condition affecting the DC bus voltage.
  • Incorrect voltage setting for the operating environment.

Repair Steps & Checklist

Click steps to track your progress.

  1. 1

    Check the incoming supply voltage at the frequency converter's input terminals to ensure it is within specified limits.

  2. 2

    If the fault was caused by a temporary supply voltage interruption, reset the fault and restart the frequency converter.

Browse all codes in this manual (26)
Verified technical data. Last updated: April 2026

Related Faults

1Overcurrent11Output phase fault111Temperature fault
Source: Vacon 20 Compact
Open Manual (Page 55)Search more codes in this manual