A VFD can provide controlled deceleration and even regenerative braking, but it cannot replace the safety function of a mechanical brake. In hoisting, the critical requirement is safe holding during power loss, emergency stops, and zero-speed load holding. If the electrical supply fails or control logic faults, the VFD cannot generate torque—yet the load still wants to move downward. A fail-safe mechanical brake (spring-applied, power-released) provides the independent safety layer that engages when power is lost.
Mechanical brakes also provide secure parking and allow safe maintenance lockout. Even in travel motions, relying solely on VFD braking can lead to drift due to wind or slope, especially on outdoor gantry cranes.
Best practice is to use the VFD for smooth routine deceleration and to minimize mechanical brake wear, while the mechanical brake provides holding, emergency stopping, and compliance with crane safety standards. Proper brake timing (set/release) with the VFD prevents shock loading and slipping.