Safe Brake Ramp (Sbr) - Siemens SINAMICS S120 Function Manual

Safety Integrated Extended Functions

5.9 Safe Brake Ramp (SBR)

5.9 Safe Brake Ramp (SBR)
If an induction motor is being used, the "Safe Brake Ramp" (SBR) Safety Integrated function
can be activated without an encoder. The Safe Brake Ramp (SBR) function provides a safe
method for monitoring the brake ramp. The Safe Brake Ramp function, safe brake ramp
monitoring (SBR) is always used to monitor braking when using the SS1 encoderless and
SLS encoderless functions.
Functional features of Safe Brake Ramp without encoder
The motor is immediately decelerated along the OFF3 ramp as soon as SS1 or SLS is
triggered. Monitoring of the brake ramp (envelope (monitoring ramp)) is activated after delay
time p9582/p9382 (SI Motion brake ramp delay time (SBR delay time), Control Unit/Motor
Module) has elapsed. Monitoring ensures that the motor does not exceed the set brake ramp
(SBR) when braking. As soon as the speed drops below the shutdown speed (p9560/p9360;
standstill detection), safe monitoring of the brake ramp is deactivated. Additional specific
functions (e.g. STO, new SLS speed limit, etc.) are activated at this point, depending on the
Safety Integrated function used
reference
frequency
standstill
detection
Monitoring ramp down time
STO selected
STO active
SS1 selected
SS1 active
SS1 active
Power removed
Figure 5-9 Safe Brake Ramp without encoder
86
Selection of SS1-ramp:
user action:
- set SS1 signal
Activation of SS1-ramp:
user action:
- none
envelope
(monitoring ramp)
OFF3 ramping
SBR delay
Deselection of SS1-ramp:
Activation of STO:
user action:
user action:
- clear SS1 signal
- none
STO
Function Manual, (FHS), 11/2009, 6SL3097-4AR00-0BP0
Starting drive:
user action:
- set OFF1/ON signal
set point
frequency
stator
frequency
rotor
frequency
time
Safety Integrated