Line safety switch for use as downstream line safety switch, has integrator determining integral of square of current value, and comparator comparing integral with preset value, where conditions are fulfilled, if preset value exceeds

摘要

The switch (18) has a latching mechanism (32) separated away from a stationary contact element (24) under preset conditions of a movable contact element (26) moved away from the element (24) and an ammeter (40) measuring a value of current flowing between input and output terminals (20, 22). An integrator (44) determines integral of square of the current value over time if and as long as the current value exceeds a preset value. A comparator (46) compares the integral with another preset value, where the preset conditions are fulfilled, if the latter preset value exceeds.