| 摘要 |
<p>An improvement to fault responsive protective devices, which employ timing capacitors, is provided by controlling the voltage of the timing capacitor by clamping it to a value slightly in excess of the voltage on a master timing capacitor. This allows the master timing capacitor to inhibit the operation of the improved fault responsive device without affecting the input to the timing capacitor. The inherent time constant produced by the timing capacitor is not altered. However, by clamping the voltage level of the timing capacitor only under appropriate conditions, the time current characteristic of the improved fault responsive protective device is altered only when those conditions occur which make it desirable to lengthen the interval before the fault responsive protective device responds to a fault.</p> |
