An electrical connector comprises two signal contacts, each having an L-shaped body portion, a first contact arm connected to a first end of the L-shaped body portion, and a second contact arm also connected to the first end of the L-shaped body portion. This element for storing a binary datum inputs a signal representative of said binary datum, said storage to be carried out when an enable signal is at a first predetermined level, supplies an output signal the state whereof represents the datum stored in said storage element, and detects an attack aimed at said enable signal or at a signal internal to said storage element. The resisting force is overcome by the opening force after the blade has been moved through a predetermined angle relative to the handle, so that the blade then opens automatically. Other than indicating the abnormality of the L-N, L-G, N-G surge absorbing devices, the present invention can prevent current leakage as destroys occurs in the diverse modes. The analog output and the digital output are then combined to yield an integrated output.