| 摘要 |
PURPOSE:To improve maintenance service by changing over power supply to a repeater from a first Zener diode to a second Zener diode and supplying power by the second Zener diode when the first Zener diode gets trouble. CONSTITUTION:Zener diodes 1-1-1-36 are connected in parallel with relays 6-1-6-36 respectively. A Zener diode 5 is installed on the monitor circuit side, and connected on the dotted line sides of the rl1-1-1-rl1-1-36 and rl2-1-1-rl2-1-36 of the contacts of the relays 6-1-6-36. When any of the Zener diodes 1-1-1-36 is short-circuited by trouble, it is changed over to the Zener diode 5, and power is supplied from the monitor circuit side. Accordingly, electric power can be supplied in non-hit, and maintenance service is improved by adding a low-cost part. |
