Dynamic Braking

In the context of industrial brakes, Dynamic Braking is the function of decelerating a moving load by converting the system’s kinetic energy into thermal energy (heat) through friction. This is the primary “stopping” action of a brake. During a dynamic stop, the brake’s friction pads or shoes are applied to a rotating disc or drum, creating a resistive torque that opposes the motion and slows the load down.

It is crucial to differentiate this mechanical action from electrical dynamic braking, a process managed by a Variable Frequency Drive (VFD). In electrical braking, the motor is temporarily turned into a generator, and the excess electrical energy is dissipated as heat through a bank of resistors.

While both methods slow a load, the mechanical industrial brake’s dynamic function is essential for three key reasons:

1. Emergency Stops (E-Stops): It provides the rapid, high-torque stopping power required to bring machinery to a halt in an emergency, independent of the drive system.
2. Final Holding: After the VFD has slowed the load, the mechanical brake engages to provide true, zero-speed static holding, which an electrical system cannot do.
3. High-Inertia Loads: It handles the immense thermal energy generated when stopping very heavy or high-speed loads, which might otherwise overwhelm the electrical braking resistors.

Therefore, the dynamic braking capability of a mechanical brake is defined by its thermal capacity—its ability to absorb and dissipate heat without experiencing brake fade or mechanical failure—and its ability to provide consistent torque for controlled, repeatable stops.