METHOD AND DEVICE FOR MONITORING CONSUMPTION OF CONTACT ELEMENTS IN A SWITCHING DEVICE

摘要

The useful life of a contactor depends in particular on the state of wear of the principal contacts. In order to prevent unexpected outages resulting from a poor operating state of the contact elements, the arc created between the contact elements as they open during the switching off operation is used as an indicator, the arc voltage being measured each time and the fluctuation in arc voltage taken as an indication of the state of wear of the contact elements. The device comprises a circuit arrangement (10) with at least one high pass (1), a square-law transfer unit (2), an integrator (3) and a fault signal generating unit (4).