Protective device for an electrical consumer

US5604476A · kind A · utility

Assignees

• Ellenberger & Poensgen GmbH
• Wilo AG · DE

Inventors

• Wolfgang Schmidt
• Ulrich Reichert · Altdorf, DE
• Fritz Krasser
• Frank Tolksdorf · Hagen, DE
• Stephan Greitzke · Dortmund, DE
• Hansjuergen Kech · Herdecke, DE

Key dates

• Filing date: Feb 13, 1995
• Grant date: Feb 18, 1997
• Expiry date: Feb 13, 2015

Classification

• Technology area (CPC H): Electricity
• CPC primary: H01H61/02
• WIPO field: Electrical machinery, apparatus, energy
• WIPO sector: Electrical engineering

Abstract

A protective device for an electrical consumer disposed in a consumer circuit. The protective device has sensor elements for detecting an operating state of the electrical consumer, and an electronic evaluation and control unit operatively connected to the sensor elements for evaluating and controlling the operating state of the electrical consumer detected by the sensor elements. The protective device further includes a protective switch responsive to the operating state of the electrical consumer for interrupting the consumer circuit. The protective switch comprises a control circuit including a bimetallic strip and a temperature-dependent resistor for deflecting the bimetallic strip for interrupting the consumer circuit, the bimetallic strip thereby defining a deflecting direction. The protective device further includes a power supply unit for supplying electrical power to the sensor elements, the evaluation and control unit and the protective switch. The improvement of the protective device pertains to a protective switch which further comprises a spring disposed for biasing the bimetallic strip and the temperature-dependent resistor toward one another in the deflection directi…