Rush current preventing circuit

Abstract

Abstract PURPOSE:To prevent rush current and to perform stable operation, by flowing an input current from a protective resistance to a solid-state relay with switching when a secondary side output voltage reaches a specified voltage or more. CONSTITUTION:When an AC power supply A is turned on, an output voltage B appeared at secondary output terminals 16 and 16' does not rise, and then the inout current of the power supply A flows to a protective resistor 5. Further, after a prescribed time, the voltage B required for starting the operation of a power supply controlling circuit reaches a normal value and a drive circuit is operative to turn on a solid-state relay SSR11. Then, the input current of the power supply A does not flow through the resistor 5 but through the SSR11 only. Thus, heating of the resistor 5, unnecessary power loss and unstable power supply can be prevented. Through constitution like this, with the SSR11 turned off, since a time of the input current flowing to the resistor 5 is a time when the voltage B rises, the heating of the resistor 5 is minimized, allowing to completely prevent rush current.

Inventors

• 👤 Toshiyuki Sogo
• 👤 十河　敏行

Bibliographic Details