SE-Power FS STO-manual vers. 1.6 en.12.08.2015
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The safety function “Safe Torque Off” (STO) can be requested via various devices. The
switch S1 can be, for example, an emergency stop switch, a safety door switch, a light
barrier or a safety switching device. The safety request is made in 2 channels via switch S1
and routes to the 2-channel switch-off of the output stage. Once the output stage has been
switched off, it is output by the floating contact C1/C2.
Notes with regard to a typical circuit:
The servo drive with safety module does not have integrated cross-circuit detection.
With direct light barrier wiring, the light barrier detects cross-circuits if designed to do so.
When using safety switching devices, the contacts C1, C2 can be integrated in the
feedback circuit of the safety switching device.
The typical circuit shows a 2-channel structure, which is suitable for categories 3 and 4
with additional measures.
Which additional measures are required depends on the range of applications and the
safety concept of the machine.
