Certain types of conveyors require fail-safe brakes for stopping. These conveyors, often used in the mining and aggregate industries, include downhill conveyors (e.g., discharge and transfer conveyors), as well as overland conveyors with downhill sections. Not having fail-safe brakes on these types of conveyors can result in catastrophic damage if power is lost. For example, overspeed can result in damage to drive system components, clogging of chutes at transfer points, or general safety issues stemming from performing an e-stop. Some unique considerations related to designing a conveyor brake system include:
A holding or e-stop brake is used to keep a drive system from moving once the variable frequency drive has reached a near stop (i.e., near zero RPM shaft speed). In a holding or e-stop braking application, the brake generally isn’t used to stop the system except for emergency situations. The brake is always fail-safe, meaning that it is spring applied and will set itself in the event of a power failure.
Below is a summary of how we determine the best fail-safe holding or e-stop brake for our customers’ industrial applications: