Afag SE-Power FS, Manual

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20 SE-Power FS STO-manual vers. 1.6 en.12.08.2015
Connections Description
STO-A (Pin 1)
0V-A (Pin 2) Control port A for the STO function with corresponding reference potential.
1)

Request for “Safe Torque Off” (STO) at Low (0 signal), together with
STO-B
STO-B (Pin 3)
0V-B (Pin 4) Control port B for the STO function with corresponding reference potential.
1)

Request for “Safe Torque Off” (STO) at Low (0 signal), together with
STO-B.
C1 (Pin 5)
C2 (Pin 6)
Feedback contact for the “Safe Torque Off” (STO) status, e.g. to an external
controller.

Feedback contact opened
:
„Safe Torque Off“ (STO) not active

Feedback contact closed
:
„Safe Torque Off“ (STO) active
24 V (Pin 7)
0 V (Pin 8) Auxiliary supply, e.g. for safety peripherals (24 V DC logic supply of the
servo drive).
1) Control inputs 24 V, high active, based on EN 61131-2, deviating signal level, see
Section 9, Table 21 .
Table 2: Function of the module connections
The connections are electrically isolated from each other in groups and from the 24 V-
supplies to the servo drive

Section 9, Table 24 .
4.2.3 Control ports STO-A, 0V-A / STO-B, 0V-B [X40]
The safety function STO (Safe Torque Off) is requested via the two control ports STO-A and
STO-B. They permit the direct connection of safe semiconductor outputs (electronic safety
switching devices, active safety sensors, e.g. light curtains with OSSD signals) and of switch
contacts (safety switching device with relay outputs, passive safety sensors, e.g. forcibly-
guided position switches)

e.g. Section 5.2.3, Figure 7 .
To request the safety function STO (Safe Torque Off), the 24 V control voltage at both
control ports STO-A and STO-B is switched off (0 V).
If the two control ports are switched off simultaneously or within a defined discrepancy time,
the STO function is active.
For control ports STO-A and STO-B, an under voltage monitoring mechanism is integrated to
eliminate the possibility of invalid voltage ranges for the downstream electronics, as well as
an overvoltage monitoring mechanism to protect against overvoltage.
Table 21 in Section 9.1.4 describes the technical data for the control ports within the
specified operating range of the logic voltages.
Tolerance ranges are defined for the input voltage range of control ports STO-A and STO-B.
The amount of energy stored in the safety module components (e.g. capacitors) depends on
the input voltage level. During switching operations, these energies must be charged or
discharged. Consequently, switch-off time values for the transition to the safe state (STO)
and the tolerance time vis-a-vis OSSD signals (buffer time) depend on the input level
The time response requirements are contained in the technical specifications in Section
9.1.4 . The time Response itself is described in section 4.4.