Sto Via Power Module Terminals - Siemens SINAMICS G120 Installation Manual

4.3

STO via Power Module terminals

Description
The "Safe Torque Off" (STO) safety function can be implemented via terminals on the power
modules of frame sizes FSD ... FSG.
Figure 4-9
The two switches have the following function:
● Both switches = ON: STO is enabled
● Both switches = OFF: STO is locked
● Two switches different: not permissible
Terminals STO_A and STO_B are low active.
Connect line to select STO
Use a SELV or PELV power supply with 24 V DC (20.4 V ... 28.8 V, maximum 60 V briefly)
for the STO_A and STO_B connections.
Use a shielded cable with the following properties:
● Length ≤30 m
● Cross section 0.5 mm
● Insulated for 600 V
Use conductor end sleeves, stripped length 7 mm.
Procedure
1. Connect the cable to select STO at terminals STO_A and STO_B on the front of the
power module.
2. Tighten the screws of the terminals with a torque of 0.2 Nm (2 lbf in).
3. Attach the shield to the shield plate of the Control Unit through the largest possible
surface area.
You have connected the STO terminals.
❒
Power Module PM240-2
Hardware Installation Manual, 01/2020, A5E33294624B AL
Terminals and switches for the "STO via power module terminals" function
... + 1.5 mm
2
4.3 STO via Power Module terminals
(20 ... 16 AWG)
2
Connecting
63