Product Description; General Description; Ax8911 With Sto Function (Ax8Xxx-X1Xx) - Beckhoff AX8-1 Series Documentation

Product description

4 Product description
4.1

General description

AX8911 - TwinSAFE drive option for AX8000 series servo drives
The AX8911 TwinSAFE drive option is an optional extension of the Beckhoff AX8000 servo drive series.
There are two versions of the AX8911 option. The first version provides only the STO function via the digital
inputs of the AX8000 axis module or via a TwinSAFE (FSoE) connection. The second version provides STO
and additionally the Safe Motion functions such as Safe Limited Speed.
The AX8911 meets the requirements of IEC 61508:2010 SIL 3, EN 62061:2005/A1:2013/A2:2015 SILCL3
and EN ISO 13849-1:2015 (Cat 4, PL e).
The AX8911 is intended for use in a servo drive from the AX8000 series, in which it is permanently installed.
4.1.1

AX8911 with STO function (AX8xxx-x1xx)

Through the integration of the AX8911 drive option in the AX8000, the STO safety function can be enabled
via two digital inputs per channel of the servo drive or via Safety-over-EtherCAT (FSoE). The digital inputs
and the signals via FSoE are equivalent and are logically ORed internally. It is therefore sufficient to enable
the axis via either one of the two ways.
The respective axis is enabled if both of its digital inputs are logic 1 (24V
inputs is logic 0, then the STO safety function is active and the motor is switched torque-free.
Alternatively, the STO function of the axis can be accessed via Safety-over-EtherCAT (FSoE). The
respective axis is enabled if the STO signal via FSoE is logic 1. If the STO signal via FSoE is logic 0, the
STO safety function is active and the motor is switched torque-free.
The AX8911 drive option is typically addressed via FSoE. The digital inputs are intended for the
commissioning of the AX8000. It is also possible via the digital inputs to operate the AX8911 drive option
with a safety controller that doesn't support the FSoE protocol.
Digital inputs and Safety-over-EtherCAT (FSoE)
If you use the FSoE connection for accessing the AX8911 drive option and additionally the
digital inputs of the AX8000 on X15 or X25 during the commissioning of the axis, make
Attention
sure that the wiring to the digital inputs is removed after the commissioning of the axis.
STO function
If the STO function described above is not suitable for the application, it must be changed
by the user or by loading a user-defined safety project into the AX8911.
Note
10 Version: 1.0.0
). If at least one of the two digital
DC
AX8911 - TwinSAFE Drive Option