Abstract: A method for detecting insufficient contact pressure between two contacts of an electrical switching unit, including a device for resetting a mechanism for controlling the switching unit following a closure maneuver of the mechanism, the resetting device including a motor configured to complete the closure maneuver of the control mechanism. The method involves detecting whether the motor completes the closure and whether a resetting torque corresponds to a normal resetting torque, by analyzing an envelope curve of current consumed by the motor over time, and, if the motor completes the closure, deducing that a wear is a result of wear in the mechanism or a kinematic chain, and if the motor completes the closure and the resetting torque corresponds to an abnormal rescuing torque, deducing that the wear corresponds to wear in the motor or parts involved in compressing the closure spring.

Abstract: A method for detecting insufficient contact pressure between the two contacts of an electrical switching unit, the unit including a device for resetting the mechanism for controlling the switching unit following closure of the mechanism, the resetting device including a motor able to complete the closure maneuver of the control mechanism. The method involves detecting whether the motor completes the closure and/or whether the resetting torque corresponds to a normal resetting torque, by analyzing the envelope curve of current consumed by the motor over time, in order to carry out the resetting following the closure manoeuvre of the control mechanism, and, if the motor completes the closure, deducing that the wear is the result of wear in the mechanism, the kinematic chain or even in the motor, and/or if the resetting torque corresponds to an abnormal resetting torque, deducing that the wear corresponds to wear in the motor or even in the parts involved in compressing the closure spring.

Abstract: A closing system for an arc extinguishing chamber of a circuit breaker with high breaking capacity has been developed. The system according to the invention comprises a first duct equipped with a set of filters able to support usual pressures caused by the gases arising from the switching arc, in particular about 10 to 12 bars, and a second duct closed by a valve device enabling direct outlet of the exhaust gases when the pressure exceeds a threshold so as to prevent any explosion of the case. The outer wall of the extinguishing chamber is designed for the circuit breaker housing so as, including in case of opening of the valve device, to direct the gases and to prevent any arc-over on the frame. The valve device comprises a suitable membrane made from polymer, in particular aramide.

Abstract: A closing system for an arc extinguishing chamber of a circuit breaker with high breaking capacity has been developed. The system according to the invention comprises a first duct equipped with a set of filters able to support usual pressures caused by the gases arising from the switching arc, in particular about 10 to 12 bars, and a second duct closed by a valve device enabling direct outlet of the exhaust gases when the pressure exceeds a threshold so as to prevent any explosion of the case. The outer wall of the extinguishing chamber is designed for the circuit breaker housing so as, including in case of opening of the valve device, to direct the gases and to prevent any arc-over on the frame. The valve device comprises a suitable membrane made from polymer, in particular aramide.