Undervoltage Alarm
Yaskawa · E7 Drive
Was bedeutet UV ?
This is a warning displayed on the digital operator during a momentary power loss event. It indicates that incoming AC power has been interrupted, but the drive's control power supply is still being maintained. The alarm signifies the drive is in a ride-thru state and will precede a UV1 fault if power is not restored within the configured ride-thru time (L2-02).
Häufige Ursachen
- Momentary interruption or sag of the incoming AC power supply to the drive, lasting for a short duration.
- Loss of one or more input phases for a very brief period due to grid instability or upstream protection.
- Weak or unstable incoming AC power supply, making it susceptible to transient voltage dips.
- Auxiliary control power supply (if external) experiencing a brief dip or interruption.
- The drive's internal ride-through capability (e.g., L2-01 setting) is being utilized during a power event.
Reparaturschritte & Checkliste
Klicken Sie auf Schritte, um Ihren Fortschritt zu verfolgen.
- 1
1. Monitor the incoming AC line voltage at R/L1, S/L2, T/L3 terminals with a power quality analyzer to detect voltage sags.
- 2
2. Inspect upstream circuit breakers and fuses for signs of intermittent tripping or loose connections.
- 3
3. Confirm all input power wiring connections at the drive are secure and free of corrosion.
- 4
4. Verify the drive's ride-through settings (e.g., L2-01) are configured appropriately for the application's power stability.
- 5
5. Consider installing a UPS (Uninterruptible Power Supply) for the control circuit or the entire drive if power quality is consistently poor.