Beckhoff AX8911, Документация

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Safe Motion functions
AX8911 53 Version: 1.2.0
7.12 Safety functions SLP, SCA
WARNING
Multi-turn position
In order to be able to use the multi-turn position for fail-safe tasks, the respective axis must be referenced
and the multi-turn position saved in the TwinSAFE Logic. This is implemented via the setting of
Max Start
Deviation in the Variable Mapping for the multi-turn position. If a discrepancy is determined when starting
up, an error will be signaled and the referencing must be repeated. This is implementable by application
means through the safety user program.
The safety functions SLP (Safe Limited Position) and SCA (Safe CAM) can be implemented via safe function
blocks FB Limit. If both safely connected variables MultiTurn_Position and SingleTurn_Position lie within the
parametrized limits, the InLimit outputs become TRUE and the FB AND output SLP_Position_Reached is
thus set to TRUE. This safe signal can be used in the following safety application. This example can be used
if the step size for the multi-turn position is 1, i.e. minimum and maximum value of the FB Limit are the same.
Fig. 27: SLP and SCA with FB Limit
If a larger position range (more than one revolution) is to be covered with SLP or SCA, the above application
must be extended accordingly, as otherwise the signal SLP_Position_Reached does not constantly return a
logic 1 within the defined range.
7.13 Safety function SBC
The brake can be controlled in the axis modules AX8xxx-x2xx and AX8xxx-x1xx (from firmware 01) via safe
outputs of the AX8911 TwinSAFE Drive Option. In the default project, the holding brake is switched via the
AX8000 controller. If the SBC safety function is to be used, it must be implemented via a user-specific safety
project on the AX8911. The control of the holding brake can be enabled from AX8911 by setting the
Brake
Control Enabled parameter to TRUE.