Current limit (VLT overload)

What does 59 mean?

The drive has reached its internal current limit due to an overload condition, similar to 'Inverter overloaded' but possibly indicating a different internal control loop limitation. This is a protection mechanism to prevent damage to the drive's power components.

• Mechanical overload on the driven equipment (e.g., jammed pump, seized bearing, excessive load on conveyor belt).
• Motor operating significantly beyond its nominal torque and current due to process demands.
• Incorrect motor data entered (e.g., P1-23 motor nominal current set too low for the actual motor).
• Ramp times (P1-41, P1-42) set too short for the high inertia load, causing excessive current surges during acceleration.
• Drive's current control loop tuning is unstable or gain values are excessively high, leading to premature current limit tripping.

Click steps to track your progress.

1. 1

   Measure the actual motor current (via LCP display P06-00) during operation and compare it against the motor's nameplate nominal current.

2. 2

   Inspect the mechanical load connected to the motor for any binding, jamming, or excessive friction that could cause overload.

3. 3

   Verify that the motor's nominal current (P1-23) is accurately set in the drive based on the motor nameplate.

4. 4

   Increase the acceleration ramp time (P1-41) to allow for a slower current build-up during startup of high inertia loads.

5. 5

   Monitor DC bus voltage (LCP display P06-01) during acceleration to rule out input voltage sag contributing to higher current draw.