Siemens 3VA1 100 A Manual

Also see for 3VA1 100 A: Operating instructions Manual

Contents

Accessories4.2 Internal accessories3VA molded case circuit breakersManual, 04/2015, A5E03603177010-02 151The diagram below uses the example of an ET200S to illustrate the conventional method ofconnecting the electronics-compatible auxiliary switch AUX, the trip alarm switch TAS andthe motor operator MO320 to a distributed I/O unit.Further information about contact reliability can be found at the end of this chapter.Auxiliary switches AUXThe purpose of auxiliary switches is to signal the position of the main contacts of the moldedcase circuit breaker. The contacts of the auxiliary switch open and close simultaneously withthe main contacts of the molded case circuit breaker.Leading changeover switches LCSLeading changeover switches signal the opening of the main contacts with a lead time of 20ms in advance of circuit breaker trips and are thus used for load shedding, for example.Trip alarm switches TASTrip alarm switches signal every circuit breaker trip, regardless of the cause of the trip. Thetrip alarm switches are operated whenever the molded case circuit breaker switches to theTRIP position.