Motor Phase Interruption Monitoring

What does LP1 mean?

Monitoring of motor phases (LP1) does not respond to an interrupted motor phase, even if C0597 = 0 or 2, because the MLP1 function block is not entered into the processing table. This means an interrupted motor phase will not be detected.

• MLP1 function block (Motor Load Phase 1 Monitoring) not activated or correctly integrated into the drive's internal processing table.
• Parameter C0597 (MLP1 Enable) incorrectly configured or not set to a value that enables active monitoring (e.g., 0 or 2).
• Motor output phase (U, V, or W) physically disconnected or having a high resistance connection at the drive terminals or motor junction box.
• Fault in the current sensing hardware within the drive that prevents accurate detection of a missing motor phase.
• Software or firmware issue preventing the MLP1 function from executing its monitoring logic despite correct configuration.

Click steps to track your progress.

1. 1

   1. Access the drive's function block editor and ensure the MLP1 function block is present and enabled in the processing table.

2. 2

   2. Verify parameter C0597 (MLP1 Enable) is set to 0 (enable without trip) or 2 (enable with trip) as required by the application.

3. 3

   3. Power down the drive, visually inspect and re-torque motor power cable connections at drive terminals T1, T2, T3 and at the motor junction box.

4. 4

   4. With the drive powered down, measure continuity of each motor phase cable from the drive output terminals to the motor terminals using a multimeter.

5. 5

   5. Compare motor current readings (P0-04) for each phase using an external clamp meter while the drive is operating to detect imbalance.