| 摘要 |
<p>PURPOSE:To easily manage a battery and to facilitate the maintenance of a control system by providing a direct current power source device, which is suppliable regardless of the presence/absence of the main power source of the control system and is commonly used for the whole system. CONSTITUTION:When a main breaker 1 or a power source switch 8 of control equipment 3 is opened, and a supply voltage from an external alternating current power source is not supplied to a direct current power source device 10, an alternating current shortage voltage relay 9 is operated, its A contact point 9a is opened, and simultaneously a B contact point 9b is closed. When the above states continue for a short time, the direct current voltage is supplied from a capacitor 15 to a memory circuit 13, when the states continue comparatively for a long time, the direct current supply voltage from an external direct current power source device 6 is supplied through a direct current power source switch 16 and a backflow preventing diode 17 to a memory backup circuit 12. Simultaneously a battery 14 and the capacitor 15 are charged, and the direct current supply voltage is continuously supplied to the memory circuit 13. Thus the management of the battery and the maintenance of the control system can be facilitated.</p> |
