5. Functional safety engineering
54
Festo P.BE-CMMP-AS-3A-HW-EN 0708NH
tion, the braking ramp (t9-t8) is parameterisable using the parameterising software
("Emergency stop brake acceleration").
Warning
DANGER!
Activating "Safe standstill" during operation causes the drive to
slowly come to a stop. For drives with a holding brake, this is ap-
plied. It is essential to ensure that the motor brake can stop the
drive motion.
2.
After reaching a speed of 0, the drive is controlled at this setpoint for a parame-
terisable switch-off delay time (t10-t9). This adjustable time is the delay required to
apply the motor holding brake. This time depends on the holding brake used and
must be parameterised by the user. For applications without a holding brake, this
time can be set to 0.
3.
After this time, the internal end stage enable is switched off by the microprocessor
(t10).
The holding brake is always applied when the "braking ramp time +
set switch-off delay" has expired, even when the drive has not
come to a stop within this time!
4.
From time t10 the "Safe standstill" can be activated (driver supply relay and end
stage enable switched off at the same time). Time (t11-t10) depends on the applica-
tion and must be defined by the user.
5.
When the driver supply relay control signal is removed (t11) the capacitors in this
circuit area discharge. Approx 80 ms (t12-t11) after removing the driver supply relay
control signal the feedback contact closes ([X3], Pin 5 and 6).
6.
At time t13, an "H" is displayed on the 7-segment display of the servo controller to
indicate a "Safe standstill". This occurs at least 30 ms after the potential-free feed-
back contact closes (t13-t12).
5.2.4
Typical applications
Emergency stop circuit
Summary of Contents for CMMP-AS-C2-3A
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