Effective speed of the brake nB_m

In frequency inverter operation there are individual travel sections of different duration and different speed. To make the thermal significance of this travel profile conceivable, the concept of the thermal effective speed of the brake n_{B_m} is introduced.

The thermal effective speed of the brake represents the time-weighted and thereby effective motor speed of the travel profile that is effective for the cooling of the brake.

This analysis is always applied when there is an overwhelming portion of time within a travel profile during which the motor is operated below the thermal breakpoint speed of the brake. All travel sections of the cycle during which the brake is electrically released are included in the determination of the thermal effective speed. The travel sections with applied brake are not analyzed.