| 摘要 |
<p>The device for protecting a low-voltage electrical power line against the overvoltages due to electromagnetic pulses which are nuclear in origin, consists of a limiting contact (12) inserted into the line, and a gas spark gap (14) connected between the line and earth. The gas spark gap fires after a few nanoseconds once the pulsed overvoltage appears, and causes a short-circuit which engenders the opening of the limiting contact (12). Once the current is interrupted, the limiting contact closes again thereby re-establishing the supply, the duration of opening of the limiting contact being sufficient for the extinction of the arc in the spark gap, avoiding any pre-priming during the establishment of the supply. <IMAGE></p> |
