| 摘要 |
PURPOSE:To obtain a zero point correcting method which is effective to correct not only the movement of a zero point resulting from the temperature change, but the movement of the zero point due to the pressure applied in common to both ends of a differential pressure transducer of a highly accurate differential pressure measuring apparatus. CONSTITUTION:When a zero point is to be corrected from the measuring state of a differential pressure transducer 6 while a valve V1 of a high pressure piping 5 and a valve V3 of a low pressure piping 7 are opened, with a valve V2 of a shortcircuiting piping 8 being closed, the valve V1 of the high pressure piping 5 is closed as the valve V3 of the low pressure piping 7 is remained opened, and then the valve V2 of the shortcircuiting piping 8 is opened. As a result, the residual pressure at the high pressure side of the differential pressure transducer 6 is freed to the low pressure side. When no pressure is left between both ends of the differential pressure transducer, the valve V3 of the low pressure piping is closed to correct a zero point. |
