| 摘要 |
PROBLEM TO BE SOLVED: To prevent overflow from a storage tank even when a water level sensor of a water server cannot normally detect the upper limit water level.SOLUTION: Water in a replaceable raw water container is pumped up into a storage tank in a casing by a pump. A water level sensor composed of a float sensor performs the lower limit detection and the upper limit detection in the storage tank. A control unit starts the pump by sensor input of the lower limit detection (step S2), and stops the pump by sensor input of the upper limit detection (steps S3, S5). The control unit measures an elapsed time from the start (step S2) and stops the pump when the upper limit detection water level is exceeded and at a prescribed elapsed time before overflow from the storage tank (steps S4, S5). If the control unit further stops the pump, the input state from the water level sensor is reset (step S6). As a result, it prevents the overflow, and also, avoids unnecessary locking. |
