| 摘要 |
<p>The invention concerns a system for diagnosing electric contact with mechanical displacement for switching electrical loads. The diagnostic system comprises: a device for detecting (10) current inversion in the electric contact (12), with an analog output (SA) supplying, when the contact is closed, a voltage Vs proportional to the residual voltage of the contact Vc, that is proportional to the current (Ich) flowing in the contact (12) and in the electric circuit (CE); a microcontroller (18) receiving at an analog input (20) the voltage Vs in the analog output (SA) of the detecting device and at a logic input (22) a first logic signal (SO) supplying to the microcontroller data concerning the electric circuit zero crossing current, the microcontroller comprising first means for acquiring the maximum analog voltage level Vsm at the terminals of the contact (12) at each alternation, at the time a maximum current passes into the load (14). The invention is applicable to electric switches, electromechanical relays, hybrid relays, diagnostic system of an electric contact.</p> |
