Safe Brake Control (Sbc) - Siemens SINUMERIK 840D sl Function Manual

Safety Functions integrated in the drive

5.5 Safe Brake Control (SBC)

5.5 Safe Brake Control (SBC)
Description
Safe Brake Control is used to control actuators that function according to the closed-circuit
principle (e.g. brake).
The command for releasing or applying the brake is transmitted to the Motor Module/Power
Module via DRIVE-CLiQ. The Motor Module then carries out the action and activates the
outputs for the brake.
Controlling the brake via the brake connection on the Motor Module is realized using a safety-
relevant, two-channel method.
Note
This function is only supported by chassis components that can be identified by the MLFB
ending ...xxx3. For this design, a Safe Brake Adapter is also needed.
To ensure that this function can be used for Blocksize Power Modules, a Safe Brake Relay
must be used. When the Power Module is configured automatically, the Safe Brake Relay is
detected and the motor holding brake type is preassigned (p1278 = 0).
A brake fault was not detected
The Safe Brake Control function does not detect faults in the brake itself - such as e.g. brake
winding short-circuit, worn brakes and similar.
If a cable breaks, this is only recognized by the Safe Brake Control function when the status
changes, i.e. when the brake is closed/opened. An interrupted cable is not detected when
using SBA.
Functional features of Safe Brake Control (SBC)
● When Safe Torque Off is selected or when safety monitoring functions respond, SBC is
performed with safe pulse cancelation.
● Unlike conventional brake control, SBC is executed via p1215 through two channels.
● SBC is executed regardless of the brake control or mode set in p1215. However, SBC is
not recommended for p1215 = 0 or 3.
● The function must be enabled via parameter.
● When the state changes, electrical faults, such as e.g. a short-circuit in the brake winding
or wire breakage can be detected.
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WARNING
Function Manual, 12/2017, 6FC5397-4BP40-6BA1
Safety Integrated