Seismic cutoff recovery method, seismic cutoff recovery program, control device and gas meter that can execute them

摘要

PROBLEM TO BE SOLVED: To appropriately determine the presence or absence of leakage on a secondary side even when a gas appliance is used on the secondary side of a shutoff valve before shutting off in the return process after seismic shutoff. SOLUTION: After the seismic cutoff process is executed, the inflow amount of gas from the primary side to the secondary side is equal to or higher than the pressure drop detection lower limit threshold value at which the pressure drop of the secondary side pressure can be detected by the pressure sensor. After executing the instantaneous opening process of opening the shutoff valve so that the amount of gas flowing into the secondary side is less than half of the amount of gas flowing into the secondary side in the normal leakage determination process as the normal leakage determination process of the next side, and the pressure after the instantaneous opening process is executed. A leak determination process is executed to determine the presence or absence of leakage on the secondary side based on the degree of pressure drop on the secondary side detected by the sensor. [Selection diagram] Fig. 2