Safe Speed Monitor (Ssm); Safe Acceleration Monitor (Sbr) - Siemens SINAMICS S120 Function Manual

Extended Functions

4.5 Safe Speed Monitor (SSM)

4.5 Safe Speed Monitor (SSM)
Description
The SSM function is used to safely indicate undershoot of a speed limit (example: for
standstill detection) in both rotary directions. A failsafe output signal is available for further
processing.
The function is activated automatically as soon as the Extended Functions are enabled with
p9301.0 = p9501.0 = 1.
NOTICE
The speed limit of the SSM function (p9346/p9546) is also used as shutdown limit for the
SBR function (safe acceleration monitoring). The SBR is deactivated if the speed is below
this limit.
The effect of the SSM safety function is therefore heavily limited if a relatively high
SSM/SBR speed limit is set and the SS1 and SS2 stop functions are activated.
Features
● Safe monitoring of the speed limit specified in p9346 and p9546
● Failsafe output signal
● No stop response
Overview of important parameters (refer to the List Manual)
● p9346 SI motion velocity limit n_x (Motor Module)
● p9546 SI motion velocity limit n_x
● r9722 CO/BO: SI motion PROFIsafe status signals
4.6

Safe Acceleration Monitor (SBR)

Description
The "Safe Acceleration Monitor (SBR)" function is used for safe monitoring of acceleration.
This safety function is not autarkic and is part of the SS1 (time and acceleration controlled)
and SS2 (or STOP B and STOP C) safety functions. A STOP A is generated if any drive
acceleration within the ramp-down phase exceeds the tolerance defined in p9348/p9548.
The monitoring function is activated after SS1 (or STOP B) and SS2 (or STOP C) are set
and is deactivated after the speed drops below the value set in p9346/p9546.
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Function Manual, (FHS) , 07/2007 Edition, 6SL3097-2AR00-0BP0
Safety Integrated