Siemens SINUMERIK 840D sl Function Manual page 305

Determining the test torque, MD36966 $MA_SAFE_BRAKETEST_TORQUE
When determining the test torque MD36966 $MA_SAFE_BRAKETEST_TORQUE, the
maximum holding torque that occurs must first be determined. The maximum occurring holding
torque can be determined in parameter r1509 by traversing the axis to various positions with
different forces / torques due to weight (tools or workpieces).
Examples to determine MD36966 $MA_SAFE_BRAKETEST_TORQUE, p2003=100Nm:
Max. holding torque
20Nm = 20%
30Nm = 30%
40Nm = 40%
50Nm = 50%
60Nm = 60%
70Nm = 70%
The "limit value of the actual torque before SBT" shown here, indicates that the actual torque,
automatically determined before the SBT, must not be lower, as otherwise Alarm 20095 "Axis
%1 inadmissible holding torque" is output.
Evaluating the test results
Analysis using servo trace
The signal characteristics must be viewed in order to evaluate the brake test. The behavior
during the brake test can be recorded using the trace and the following settings:
Signal selection
System deviation
Following error
Torque limit
Torque-generating actual current value i(q)
Measurement parameters
Measurement duration: 10 s
Trigger: No trigger
Safety Integrated
Function Manual, 12/2017, 6FC5397-4BP40-6BA1
M r1509
0max
26 %
39 %
52 %
65 %
78 %
91 %
Test torque
M =M + 30%
T 0max
Connecting sensors and actuators
8.6 Safe Brake Test (SBT)
Actual torque limit before SBT
M *0.85
T
22.1%
33.15%
44.2%
55.3%
66.3%
77.4%
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