Power Loss

What does F003 mean?

Single-phase operation has been detected, combined with an excessive load on the motor. This condition typically arises from a lost phase on the incoming AC line or a severe voltage sag, causing the drive to struggle under load. It can lead to motor and drive overheating if unresolved.

• Lost phase on the incoming AC line (e.g., L1, L2, or L3) due to a blown fuse, tripped circuit breaker, or open-circuited main contactor pole.
• Loose or corroded connections on the main power input terminals (e.g., R, S, T) of the drive or upstream power distribution components.
• Severe voltage unbalance exceeding 2% between incoming AC phases due to grid instability or disproportionate loading on the supply transformer.
• Malfunctioning upstream power contactor failing to close all three poles simultaneously or maintaining continuity under load.

Click steps to track your progress.

1. 1

   Measure incoming AC line voltages (L1-L2, L2-L3, L3-L1) at the drive's input terminals (R, S, T) with a voltmeter, verifying they are balanced within 2% and at nominal voltage.

2. 2

   Inspect all main power fuses upstream of the drive, testing continuity with an ohmmeter, and replace any open or damaged fuses.

3. 3

   Tighten all main power terminal connections (R, S, T) at the drive and the upstream disconnect switch or contactor according to manufacturer's torque specifications.

4. 4

   Check the operation of the upstream main contactor, ensuring all three power poles close simultaneously and maintain continuity when energized.

5. 5

   Monitor the DC bus voltage (P0-03 [DC Bus Voltage]) for stability and proper charging after power application, indicating a healthy input.