ABB ACS880-104 Hardware Manual page 156

156 Electrical installation
STO OUT
9. Connect an ACS-AP-x control panel to X13 on the BCU control unit.
10. If the modules are equipped with option +C183 (heating elements), connect a
230/115 V AC (50/60 Hz) supply to X50:7...8.
STO signal forwarding output to next inverter module (if
X51 present)
STO signal forwarding output to next
inverter module (if present)
STO IN
STO signals from BCU control unit
X52
STO signals from BCU control unit