PURPOSE: To improve the reliability of automatic control by detecting abnormality of an external water gauge with water level variation time set beforehand taking amount of the tidal cycle in automatic gate control of a dam at estuary.
CONSTITUTION: Based on a water level data from an external water level, a time TN indicating no water level change is detected with a water variation time monitoring device 3. The time TN is fed to a comparator with the preset time TS of a water level variation time setting device. When the requirement of TN≤TS is met, a control mode to be executed is determined with a control mode decision device 6 while a gate control volume is determined wlth a gate action calculator. Then a control command is sent to a gate opening/closing device 8. When the requirement of TN≥TS is met, a warning is given outside with an alarm 9. At the same time, a stop command is sent to the device 8 to halt the automatic control of the gate.
SHINOMIYA FUMITO
KUBOTA SATORU
