Siemens SENTRON 3WL10 - Design of the Circuit Breaker; Withdrawable Breaker

2.8.2 Design of the circuit breaker
The circuit breaker contains the contacts (3 or 4 poles), the switching mechanism, and the
internal accessories, comprising an operator and contact system and the internal accessories.
Each of the poles is contained in a separate plastic enclosure and consists of the interrupting
contact system and a current transformer.
Main components of the 3VA27 & 3WL10 circuit breakers
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① Area with front / rear connections
② Auxiliary conductor terminal system
③ Electronic trip unit (ETU)
④ Switch position indicator contacts OPEN / CLOSED
⑤ "Mechanical ON" pushbutton
⑥ "Mechanical OFF" pushbutton
⑦ Status indicator of spring energy store CHARGED / DISCHARGED
⑧ Manual lever for charging the spring energy store
⑨ Handle operating mechanism
⑩ PUSH TO TRIP: initiates a mechanical trip
2.8.3 Withdrawable breaker
The withdrawable version of the circuit breaker is not permanently mounted in the control
panel. Instead a guide frame holding the circuit breaker is mounted in the control panel. The
busbars and cables are connected to this guide frame. When the circuit breaker is inserted into
the guide frame, the main circuit connection is established. In the retracted position, built-in
shutters ensure safe touch protection of the main circuit connections.
In this way, the circuit breaker can be removed from the guide frame without disassembly
work and removed from the control panel if required.
Description
2.8Basic unit
3VA27 molded case circuit breakers & 3WL10 air circuit breakers
Equipment Manual, 10/2023, L1V30499596002-03 31