| 摘要 |
PURPOSE:To always achieve an accurate measurement of water level by determining difference between air pressure of a measuring valve tube when air bubbles generate from the lower end and that of a reference valve tube to effect correction with the ratio between the differential pressure at the reference specific gravity and that at the actual measurement. CONSTITUTION:A measuring device is provided with a pressure detector 18 and an additional pressure detector 21. The pressure detector 18 detects the air pressure P2 of a measuring valve tube 13, the other pressure detector 21 a valve P2-P1 from the air pressure P2 of the measuring valve tube 13 and the air pressure P1 of a reference valve tube 14 obtained through a second valve 19 while the atmospheric pressure P0 through a third valve 20. With such an arrangement, as the air pressure P2 is detected with the detector 18 and the valve P2-P1 with the detector 21, the correction calculation of P2X(P2-P1)/DELTAP can be always done to correct variation in the specific gravity thereby enabling an accurate measurement of water level. |
