| 摘要 |
PURPOSE: An alarm device for a switchboard is provided to improve stability by prohibiting people without a terminal box key from opening the terminal box. CONSTITUTION: A key switch(20) turns on a main power supply unit. If a handle switch(30) is rotated while a terminal box key is inserted, is turned on. A timer(40) is electrically connected to the handle switch. A relay(50) is electrically connected to a timer. A voice informing part(60) is electrically connected to a contact point of the relay and generates a voice signal when the relay is turned on. |
