E.IPF

Instantaneous Power Failure Protection

Mitsubishi Electric · A500 Inverter

What does E.IPF mean?

This protection activates if the main power supply (inverter input R, S, T or L1, L2, L3) experiences a power failure lasting longer than 15 milliseconds. It stops the inverter output to prevent control circuit malfunction. During the event, the alarm warning output contacts switch state (open across B-C, close across A-C). If the power failure duration exceeds 100 milliseconds, the alarm warning output is not provided, and the inverter may attempt to restart automatically if a start signal is present upon power restoration.

Common Causes

  • Sudden loss of main power supply during operation.
  • Brownout or voltage sag that triggers the protection.
  • Internal power supply unit failure within the main control board.
  • Faulty power factor correction circuit or capacitor.

Repair Steps & Checklist

Click steps to track your progress.

  1. 1

    Monitor the incoming power supply voltage at the inverter input terminals (R, S, T or L1, L2, L3) for sags or interruptions lasting more than 15ms using a power quality analyzer.

  2. 2

    Verify the stability and reliability of the upstream power source and any associated circuit breakers or contactors.

  3. 3

    Check for the presence and functionality of any backup power supply (e.g., UPS) or ride-through option designed to bridge momentary power losses to the inverter.

  4. 4

    Consult page 89 of the inverter manual for parameters related to automatic restart after instantaneous power failure and verify their settings.

Browse all codes in this manual (21)
Verified technical data. Last updated: March 2026

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Source: Mitsubishi Electric A500 Inverter