Method for detecting insufficient contact pressure in a switching unit, device for implementing such a method, and switching unit including such a device

A method for detecting insufficient contact pressure between the two contacts of an electrical switching unit, said unit comprising means for resetting a control mechanism for controlling the switching unit following closure of the control mechanism, said resetting means comprising means for compressing a closure spring intended to bring the mechanism for controlling the switching unit to a position in which the control mechanism is ready to close, said resetting means also comprising a motor able to complete the closure manoeuvre of the control mechanism, in the event of incomplete closure by said control mechanism and before carrying out the resetting, said insufficient contact pressure being the result of wear in the control mechanism, the kinematic chain, the motor, the parts involved in compressing the closure spring, or in the event of incomplete closure exclusive of any wear,

• wherein said method comprises detecting whether the motor completes the closure and/or whether the resetting torque corresponds to a resetting torque called normal resetting torque, by analysing 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.