23
item Controller BL 1-04 /C
― Product manual
4.6.1 Safe torque off (STO)
1
Servo drive with an integ
-
rated STO function (only
the relevant connections
are shown)
2a
Emergency stop button
2b
Safety gate
2c
Light grid
2d
Safety relay
OSSD
24V DC
0V DC
1
S1
2a
2b
2c
2d
Figure 6: Connection of the integrated STO function (single-phase servo drive)
The "Safe Torque Off" (STO) safety function can be requested by various devices. Switch S1 can be, for example, an emergen
-
cy-stop switch, a switch of a protective gate, a light grid or a safety relay. The safety request is realised via two channels and
via the switch S1. As a result, the output stage will be switched off via two channels.
Notes concerning the circuit example
▪ The servo drive with an integrated STO function does not include any cross-circuit detection. In the case of a direct wiring
of light grids, the cross-circuit detection will be performed by the light grid, provided that it is suitable for this purpose.
▪ The circuit example has a two-channel structure that is suitable for category 3 and 4 if additional measures are implement
-
ed. The additional measures depend on the area of application and on the safety concept of the machine.
