9
Malfunctions
Encoder malfunctions
Operating Instructions – CM3C63 – 100
111
9.3.2
BZ.. brake
Fault
Possible cause
Measure
Brake does not re-
lease
Brake control unit failed.
Install a new brake control system, check
internal resistance and insulation of brake
coil, check switchgear.
Brake connected incorrectly.
Check brake connection.
Max. permitted working air gap ex-
ceeded because brake lining worn
down.
Contact SEW-EURODRIVE.
Replacement of the brake lining carrier by
SEW‑EURODRIVE-trained staff.
Brake coil has interturn fault or short cir-
cuit to exposed conductive part.
Check switching devices.
Replace complete brake and brake control.
Contact SEW-EURODRIVE.
Brake lining worn down.
Contact SEW-EURODRIVE.
Replacement of the brake lining carrier by
SEW‑EURODRIVE-trained staff.
Incorrect voltage at brake control unit.
Apply correct voltage. Specified brake
voltage on the nameplate.
Voltage drop along the incoming cable
> 10%.
Provide for correct connection voltage.
Specified brake voltage on the nameplate.
Check cable cross section of brake cable. If
necessary, increase cross section.
Rectifier defective.
Replace rectifier and brake coil; it may be
more economical to replace the complete
brake.
Contact SEW-EURODRIVE.
Brake does not ap-
ply/brake.
Brake lining worn down.
Replacement of the brake lining carrier by
SEW‑EURODRIVE-trained staff.
Incorrect braking torque.
Check the project planning. If necessary,
adjust braking torque by changing the type
and number of brake springs.
Contact SEW-EURODRIVE.
Manual brake release device not set
correctly.
Set the adjusting nuts correctly.
Brake is applied
with time lag
Brake is switched on AC voltage side.
Switch both, the DC and AC voltage sides;
observe wiring diagram.
Noise/squeaking
near the brake
Brake parameters set incorrectly in the
inverter.
Check brake release and application times.
9.4
Encoder malfunctions
Encoder malfunctions are displayed at the inverter with a corresponding error mes-
sage.
26870460/EN – 05/2021
