Siemens SENTRON 3VA1 Manual page 299

Depending on the position of the molded case circuit breaker in the draw-out unit, the
outputs of the position signaling switches assume one of the following states:
Signal "Draw-out unit locked / open"
①
②
3VA molded case circuit breakers with IEC certificate
Manual, 03/2019, A5E03603177010-03
Slot for position signaling switch for signal "Draw-out unit locked / open"
Plastic frame for padlock locking unit
4.4 Plug-in and draw-out technology
Accessories
297