| 摘要 |
<p>A device for testing earth leakage circuit breakers detects the time period (T) between a fault being introduced between a current carrying circuit and earth and the circuit breaker interrupting the current flow, a time delay (t) being introduced to the sampling in order to avoid false indication of contact breaker opening upon zero crossing. The time delay occurs at the start of earth leakage as well as at the end of earth leakage, so that no error is introduced.</p> |
