3 Safety-Related Functions
11.03
3.8 Safe braking ramp (SBR) (840D from SW 4.2)
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SINUMERIK 840D/SIMODRIVE 611 digital SINUMERIK Safety Integrated (FBSI) - Edition 11.03
3.8 Safe braking ramp (SBR) (840D from SW 4.2)
This function is based on the assumption that after a stop request the actual
speed must decrease (monitors the speed characteristic).
Note
Regarding 840D/611 digital:
The function exists in both monitoring channels and must also be
parameterized in both channels.
The most important features include:
Fastest possible detection if the axis starts to re-accelerate during the braking
process
SBR is automatically activated when
a STOP B or C has been triggered
STOP A is triggered when SBR responds
When a stop request is triggered, the actual speed plus the speed tolerance
defined in the machine data is activated as the speed limit. This limit is
compared with the actual speed (must decrease or remain the same) and is
cyclically corrected. If the axis starts to re-accelerate while braking, this is
detected as quickly as possible.
Machine data for SBR speed tolerance:
For 840D
MD 36948: $MA_SAFE_STOP_VELO_TOL
For 611digital
MD 1348: $MD_SAFE_STOP_VELO_TOL
The speed limit value is corrected until the speed defined in the next machine
data is undershot. After that, the speed limit value n
x
is frozen to the value in
MD 36946/1346 plus the value in MD 36948/1348.
For 840D
MD 36946: $MA_SAFE_VELO_X (speed limit n
x
)
For 611 digital
MD 1346: $MD_SAFE_VELO_X
Description
Function features
Activating SBR