This invention, the fluid passing, measures the pressure inside the system which flows, especially regards the method of operating the pressure measurement equipment in order to measure the pressure of the external circuit of medical unit. The pressure measurement equipment flows, has the fluid passing when operating of the boundary attaching and system with the flexible membrane, or the pressure sensor which is connected to the aforementioned membrane with purpose of the measurement chamber and the pressure measurement which are filled up in the fluid and. Way step and set the aforementioned membrane (13) of the b. aforementioned measurement chamber (12) away from the aforementioned pressure sensor (14) step and the c. aforementioned measurement chamber (12) where this method in a state where a. aforementioned membrane (13) is not connected to the aforementioned pressure sensor (14), rises the pressure of the aforementioned measurement chamber (12) to the pressure value which barely curves at least in facing outside vis-a-vis the aforementioned measurement chamber (12) or that way verifies the existence of pressure value the aforementioned membrane (13) touches to the aforementioned pressure sensor (14), aforementioned measurement chamber (12) the aforementioned membrane (13) and step and the d. aforementioned step a which connect with the aforementioned pressure sensor (14). - C. specified interval can be less crowded, and/or the step which it repeats when occurring of error inclusion of every staff do necessity, including, it is.< Selective figure >Figure 1本発明は、流体が通過して流れる系内の圧力を測定し、特には医療ユニットの体外回路の圧力を測定するための圧力測定装置の動作の方法に関する。圧力測定装置は、可撓膜によって境界付けられ、系の動作時に流体が通過して流れ、又は流体で満たされる測定チャンバと、圧力測定の目的で前記膜に接続された圧力センサと、を備えている。本方法は、a.前記膜(13)が前記圧力センサ(14)に接続されていない状態において前記測定チャンバ(12)に対して少なくともわずかに外向きに湾曲する圧力値に前記測定チャンバ(12)の圧力を上昇させ、又はそのよう圧力値の存在を確認するステップと、b.前記測定チャンバ(12)の前記膜(13)を前記圧力センサ(14)から離すステップと、c.前記測定チャンバ(12)の前記膜(13)が前記圧力センサ(14)に接するように前記測定チャンバ(12)の前記膜(13)と前記圧力センサ(14)とを接合するステップと、d.前記ステップa
