VALVE DEVICE

PURPOSE:To confirm abnormality before a cutoff valve operates and to enhance the safety growth in the case of executing the restoration of the cutoff valve by measuring the pressure of a primary or a secondary pressure passage of a valve device with a pressure sensor. CONSTITUTION:A device is constituted so that primary pressure and secondary pressure are applied to a pressure sensor 36 through opening/closing valves 37, 40, respectively, the primary pressure or the secondary pressure is measured in accordance with necessity by opening alternatively two opening/closing valves 37, 40 by a controller 28, and this measured value is known by a display, etc., through the controller 28. In such a manner, the present primary pressure or secondary pressure can be known, especially, by always detecting secondary pressure, abnormal pressure can be known beforehand, and also, whether secondary pressure drops enough after a cut-off operation or not can be discriminated, and moreover, a measured value obtained from plural valve devices can be monitored by an automatic centralized supervisory system.