Abstract: The invention consists in using current transformers incorporated in the electronic relays of a switchboard protective device and in connecting thereto current measurement indicators located on the front face of the switchboard.

Abstract: The present invention relates to a multi-pole circuit breaker with an interchangeable magneto-thermal tripping unit electrically and mechanically connected to the breaker unit by means of connecting screws. The connecting lugs of the breaker unit are positioned with vertical play in transverse slots in the breaker unit casing and are electrically connected to the movable contacts by flexible connections. When the connecting screws are tightened the breaker unit connecting lugs are shifted to bear on the associated tripping unit lugs irrespective of any positioning defects. A reset spring of the electro-magnetic tripping device is anchored on one end on the armature and on the other end to the tripping device adjusting bar.

Abstract: A multi-pole circuit breaker having a molded case and a contact operating mechanism supported in said case. The mechanism is controlled by a handle and a trip device. To obtain the reset of the trip hook when said trip device has opened the contacts, a rocker secured to the handle engages a drive lever forming an extension of the upper link of a toggle joint of said mechanism. The catch of the trip device is biased into an intermediate balanced locking position by means of a spring and is positioned onto a pivot pin by means of radial projection insides the bore of the catch which fits into a matching groove of the pin.