| 摘要 |
PROBLEM TO BE SOLVED: To provide a content amount measuring device and a fuel filling system having the same capable of suppressing unnecessary electricity consumption.SOLUTION: A liquid amount measuring device 20 of a fuel filling system 1 includes: a second circuit C2 (namely, a second liquid amount measuring sensor 32 and a liquid amount signal transmitting part 41) for working on electricity supplied from a standby power source part PS2 of a vehicle, measuring a liquid amount of a fuel tank 10 of the vehicle, and transmitting a liquid amount signal indicating the liquid amount to the outside of the vehicle; an FET 82 provided between the standby power source part PS2 and the second circuit C2, for connecting them by closing the circuit and cutting them off by opening the circuit; and a first MPU 84 for detecting an ON state and an OFF state of a main power source part PS1 of the vehicle, measuring duration time Tk of the OFF state of the main power source part PS1, and closing the FET 82 when the main power source part PS1 is in the ON state, and opening the FET 82 when the duration time Tk exceeds predetermined cutting off determination time Ts. |
