摘要 |
<p>An electronic switch employing two input lines, but overcoming the problem in installation of the conventional 3-line electronic switch and the problem in power consumption and power stability of the conventional 2-line electronic switch. The switch comprises a) a power supply including a pair of diodes, each of which is inserted in series between the first and second lines, and both of which is connected parallel in the opposite polarity; a transformer for raising the voltage appearing across the diodes; a first rectifier for rectifying the raised AC into DC; a second rectifier for rectifying the current from the first line, when the first and second lines are disconnected due to the lamp-off, b) a voltage regulator, including a means for suppressing abnormal rise in the output voltage of the voltage supply, and c) a relay drive including a relay which is operated by DC voltage from the voltage supply, whereby the relay is a self-holding relay that once activated by the current flowing the coil, the relay remains the activated state even though the voltage is removed.</p> |