Siemens Aktiengesellschaft

Alf Wabner

Ludwig Niebler

Norbert Zimmermann

Bardo Koppmann

Fritz Pohl

Norbert Mitlmeier

Peter Hartinger

Robert Adunka

Bernhard Streich

Siegfried Neumann

A protective device is disclosed for combination with an electrical switching device including a main current line or for integration in such a switching device. In at least one embodiment, the protective device includes a switching element and a switching apparatus, which is provided for the actuation of the switching element and is influenced by a current flow through the main current line. In at least one embodiment, in order to influence the switching apparatus, a current transformer is integrated in the main current line and an electrical resistance of a secondary winding surrounded by the current transformer can be measured. A method for operating a protective device is also disclosed wherein the switching apparatus is triggered so as to actuate the switching element if the measured resistance reaches or exceeds a predetermined or predeterminable threshold value.

Protective device and method for its operation

A method and a device are disclosed for the secure operation of a switching device including at least one main contact which can be switched on and off and which includes contact pieces and a displaceable contact bridge, and at least one control magnet which includes a displaceable anchor. The anchor and the contact bridge are actively connected to each other such that the corresponding main contact can be opened or closed when switched on and off. In at least one embodiment, the method includes the following: a) the path difference, which returns the anchor after switching on and off, is recognised, b) devices which are used to open welded main contacts are released by a release device when the recognised path difference exceeds a predetermined value and a specific time duration of time has run out after switching off.

Method and device for the secure operation of a switching device

A method and a device for the secure operation of a switching device are disclosed, including at least one main contact which can be switched on and off and which includes contact pieces and a displaceable contact bridge, and also at least one control magnet which includes a displaceable anchor. The anchor acts upon the contact bridge when it is switched on or off such that the corresponding main contact is opened and closed. In at least one embodiment, the method includes: a) the displaceable contact bridge of the at least one main contact recognizes when an opening point has been exceeded after being switched off, and b) the additional operation of the switching device is interrupted, according to a predetermined duration of time, when the opening point is not exceeded.

A method and a device are disclosed for the secure operation of a switching device including at least two main contacts which can be switched on and off and which includes respectively, contact pieces and a displaceable contact bridge, and at least one control magnet which includes a displaceable anchor. The anchor acts upon the contact bridge when it is switched on and off such that the corresponding main contact is opened or closed. At least one embodiment of the inventive method includes the following steps: a) release device for a force element remains in a first state in order to interrupt the main contact as long as the main contacts are closed when switched on and open when switched off, and b) the release device are transferred into a second state if at least the main contact is welded after switching off.

An electromechanical switch includes a main contact provided with a number of main fixed contacts and a mobile main contact bridge; an auxiliary contact which precedes the main contact in the switch-on process and includes a number of auxiliary fixed contacts and a mobile auxiliary contact bridge; and a contact bridge carrier for actuating the main contact bridge and the auxiliary contact bridge. At least one of the contact parts is spring-mounted. The electromechanical switch has two stable positions of the auxiliary contact bridge or the auxiliary fixed contact. During the switching on process carried out by actuation of the contact bridge carrier via the auxiliary contact bridge or an auxiliary fixed contact in the first stable position, the auxiliary contact closes before the main contact, and during the switching off process by actuation of the contact bridge carrier in the opposite direction, the auxiliary contact with the auxiliary contact bridge or the auxiliary fixed contact in the second stable position opens before the main contact.

Growing community of inventors

Amberg, Germany

Alf Wabner