Abstract: The present invention is an industrial switching device which prevents a false indication of an open electrical circuit when contacts within the switching device are welded shut. Under normal operation, an actuator is selectively moved between a first position and a second position to reciprocally move a plunger to open and close the contacts. The actuator includes an indicator of whether the switching device is in the “ON” or “OFF” state. When the contacts are welded shut, a plunger engagement section interlocks with an actuator engagement section to prevent the actuator from moving from the “ON” position to the “OFF” position. A crossbar on the plunger engagement section embeds in the actuator engagement section to prevent the actuator from sliding over the plunger. A side member on the plunger engagement section prevents the actuator from sliding around the plunger.

Abstract: A device for measuring current comprises a magnetic field sensor for measuring the magnetic field produced by a current I flowing through a current conductor and a yoke of a magnetic material with a relative permeability of at least 100. The magnetic field sensor preferably comprises a semiconductor chip with at least one Hall element and an electronic circuit for the operation of the Hall element. The yoke consists of an oblong piece of sheet metal or a laminate of sheet metals with two ends, that has been brought by bending into a form in which the front sides of the ends of the yoke face each other and are separated by an air gap. The ends of the yoke may be flush, tapered, or flayed relative to the width of the yoke.

Abstract: A device for measuring current comprises a magnetic field sensor (2) for measuring the magnetic field produced by a current I flowing through a current conductor (1) and a yoke (3) of a magnetic material with a relative permeability of at least 100. The magnetic field sensor (2) preferably comprises a semiconductor chip with at least one Hall element and an electronic circuit for the operation of the Hall element. Two magnetic field concentrators (7, 8) separated by an air gap (6) are arranged on a surface of the semiconductor chip such that field lines (9) of the magnetic field (see FIG. 3) that issue from the first magnetic field concentrator (7) in the vicinity of the air gap (6) and impinge on the second magnetic field concentrator (8) in the vicinity of the air gap (6) pass through the at least one Hall element.