| 摘要 |
<p>An electrical safety device includes a programmable controller, a switching stage operable by the controller to connect or disconnect a load circuit from a source of power, and a residual current detection stage connected to the controller and operative in a self-test mode to send a fault signal to the controller in the event of detection of residual currents in the load circuit. The controller operates in accordance with a program to cause the switching stage to disconnect the load in response to the fault signal. The controller is also operable to apply a test signal to the residual current detection stage to simulate presence of a residual current in the load circuit and to monitor the response of the residual current detection stage.</p> |
