Positive safety control device

US4063181A · kind A · utility

Assignee

• COMMISSARIAT A L'ENERGIE ATOMIQUE ET AUX ENERGIES ALTERNATIVES · FR

Inventors

• Claude Lefebvre · Dunkerque, FR
• Jean-Paul Therond · Versailles, FR

Key dates

• Filing date: Dec 3, 1975
• Grant date: Dec 13, 1977
• Expiry date: Dec 3, 1995

Classification

• Technology area (CPC G): Physics
• CPC primary: G05B11/14
• WIPO field: Control
• WIPO sector: Instruments

Abstract

In a nuclear reactor protection system, the control device initiates reactor shutdown when the amplitude of a voltage signal delivered by a detector oversteps a range limited by two adjustable values. The device comprises a stabilized supply, a detector supplied by a rectifier for delivering a d.c. voltage having an amplitude Ve which is proportional to the value of the signal to be measured, two generators for producing d.c. voltages of opposite sign having amplitudes Vd and Vref, and an adjustable voltage divider which delivers a periodic rectangular-wave voltage having an amplitude Vs. The detector output voltage is compared with the algebraic sum of the values Vd, Vref and Vs by means which produce a voltage level of 0 if the amplitude Ve is outside the range (Vd + Vref, Vd + Vref + Vs) and a voltage level of +1 if the amplitude Ve is within said range.