PRESSURE MEASURING INSTRUMENT

PURPOSE:To find a hole in a seal diaphragm early even if the hole is formed in the seal diaphragm and to repair the instrument at an actual site in a short time by installing an isolating device consisting of partition walls between equipment and the measuring instrument. CONSTITUTION:Isolation devices 30 and 31 each formed by charging liquid for pressure transmission between two seal diaphragms are installed between tanks 1, 8 and 5 containing liquid to be measured and the instrument 14 and isolation film displacement detectors are provided to the isolation devices 30 and 31. Further, other seal diaphragms are fitted in contact with the seal diaphragms of the isolation devices 30 and 31 and the liquid for pressure transmission is charged between the seal diaphragms and the pressure measuring instrument. Consequently, even when the isolation devices 30 and 31 and the pressure measuring instrument are separated, no charged liquid leaks, so only the isolation devices 30 and 31 can be replaced individually. Further, if the charged liquid of the isolation devices 30a and 31 leaks out or if air enters the charged liquid, the seal diaphragms deforms, so the isolation films displacement detectors detect the abnormality in its early stage and repairing operation is completed in a short time.