PRESSURE DETECTORS

Pressure Detectors PRESSURE DETECTORS PRESSURE DETECTORS Many processes are controlled by measuring pressure. This chapter describes the detectors associated with measuring pressure. EO 1.1 EXPLAIN how a bellows-type pressure detector produces an output signal including: a. Method of detection b. Method of signal generation EO 1.2 EXPLAIN how a bourdon tube-type pressure detector produces an output signal including: a. Method of detection b. Method of signal generation Bellows-Type Detectors The need for a pressure sensing element that was extremely sensitive to low pressures and provided power for activating recording and indicating mechanisms resulted in the development of the metallic bellows pressure sensing element. The metallic bellows is most accurate when measuring pressures from 0.5 to 75 psig. However, when used in conjunction with a heavy range spring, some bellows can be used to measure pressures of over 1000 psig. Figure 1 shows a basic metallic bellows pressure sensing element. Figure 1 Basic Metallic Bellows Rev. 0 Page 1 IC-02