"Safe Brake Control" (SBC) supplies a safe output signal to drive an external mechanical brake. The brakes used must be “safety brakes”, in which a quiescent current operates against a spring. If the current flow is interrupted, the brake will engage. Control modules frequently include a power reduction feature when the brake is released to reduce energy consumption or brake heating. A safe brake test may be required to detect errors during operation, depending on the risk analysis. Holding brakes and service brakes are often used on axes with suspended loads.
The Safe Brake Control function is generally used to control the holding brake activated once an axis is at standstill.