PURPOSE: To manufacture a small-sized protective circuit having excellent surge inhibiting properties by connecting an arrester with a gap and the gapless varister of a nonlinear type element in parallel between the grounding side of an input power and the frame ground of an equipment.
CONSTITUTION: One line of a power supply from a pole transformer 2 is grounded at E1. An electronic circuit 10 is supplied with the power supply through surge protective circuits 11, 12. An arrester 14a with a gap and a gapless varister 14b are connected in parallel between the grounded line B of the power side and the frame ground FG of the electronic circuit 10. When lightning surge currents flow through a ground E1 and voltage is generated between B and FG, the rise of surge voltage is inhibited by the varister 14b, and surge currents are made to flow, thus inhibiting the gradual rising of the discharge voltage of the varister 14b by the use of the arrester 14a.
NARITA KAZUTOYO
HARADA YUJI
TOSHIBA ENGINEERING CO
JPS61110985A | 1986-05-29 |
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