Brake resistor power limit

What does 26 mean?

The power transmitted to the brake resistor, calculated as an average over the last 120 seconds, exceeds 90% of its capacity. If option [2] Trip is selected in parameter 2-13 Brake Power Monitoring, the frequency converter trips when dissipated braking power reaches 100%.

• Frequent or prolonged regenerative braking operations exceeding the brake resistor's average power rating.
• Brake resistor is undersized for the application's regenerative energy requirements (e.g., too low a continuous power rating).
• Deceleration ramp times (P3-42) set too aggressively, generating high peak regenerative power that averages to exceed capacity.
• Faulty brake chopper control causing it to dissipate energy inefficiently or excessively.
• Parameter P2-13 (Brake Power Monitoring) set to [2] Trip, causing a trip rather than just a warning.

Click steps to track your progress.

1. 1

   Monitor the actual brake resistor power dissipation (e.g., via LCP if available) during regenerative operations.

2. 2

   Increase the deceleration ramp time (P3-42 Decel Ramp Time) to spread regenerative energy over a longer period.

3. 3

   Verify the brake resistor's specified continuous power rating and compare it to the application's maximum regenerative power.

4. 4

   Consider upsizing the brake resistor to one with a higher continuous power rating (e.g., from 1kW to 2kW).

5. 5

   Change parameter P2-13 (Brake Power Monitoring) to option [1] Warning to allow continued operation with a warning state.

6. 6

   Check the drive's load profile and cycle time to determine if the application inherently requires a larger resistor.