| 摘要 |
PURPOSE:To prevent overdischarge of battery, to eliminate chattering and to obviate the necessity of self-holding circuit after start of operation by isolating a load from a battery upon drop of battery voltage below a predetermined level thereby preventing overdischarge of battery while furthermore isolating the battery and a voltage detector simultaneously thereby preventing overdischarge of the battery. CONSTITUTION:When a commercial power supply AC is conducting, current flows through the exciting coil of a relay Ry and a battery 2 is connected in parallel with the output of a charging circuit 1 through a relay contact r0 and charged. Current also flows through the exciting coil of an electromagnetic contactor Mg thus feeding a load 4 with power. Upon interruption of the commercial power supply AC, the electromagnetic contactor Mg and the relay Ry are fed with exciting current from the battery 2 and thereby connection between the load 4 and the battery 2 is sustained and the battery 2 is discharged. When the battery 2 voltage reaches an overdischarge protective voltage, the battery 2 is isolated from a voltage detector 5 and the load 4 on the circuitry thus interrupting discharge of the battery 2. |
