Hong Yi Wo Instrument Co., Ltd. (Zhejiang Division): 1 Description: EJA differential pressure / pressure transmitter is Japan's Yokogawa Electric Corporation mid-nineties latest product, the first to adopt a true digital sensor - crystal silicon resonant sensor, creating a new era of the transmitter, the product has a higher accuracy, stability, reliability, since the market has aroused widespread public acclaim. To meet the fieldbus era, we have launched the Foundation for testing and certification of compliance with the standard FF fieldbus transmitter. 2 Main Features: · In addition to ensuring accuracy, but also to achieve a static pressure, temperature and other environmental performance with minimal impact. · Long-term continuous use of high reliability. · Compact and lightweight, making it free from the installation site restrictions, free installation. · Using micro-computer technology, with complete self-diagnostic functions and communication functions. · Importance when developing zero stability, improve maintenance efficiency. · Consecutive years without adjustment zero. 3 Advanced principle using micro processing technology (MEMS) on a silicon chip surface and the center of the production of two edges of the shape, size, material is completely consistent H shape of the resonant beam, beam self-oscillating resonant circuit for the high frequency oscillation (Figure 1). Upper and lower surfaces of monocrystalline silicon wafer by varying the pressure generated when the deformation, leading to the center beam resonance frequency decreases by the compression force, tensile force due to the edge of the resonant frequency increases (Figure 2). Two frequency difference signal directly to the CPU for data processing, and then (a) the D / A converting 4-20mA output signal, communications, or Hart digital signal superimposed Brain; (2) directly to the output line with Fieldbus (Fieldbus Foundation TM ) standard digital signal. 4 Static pressure of excellent performance when added with negligible static pressure (working pressure), the two shape, size, material is completely consistent with the same resonant beam deformation, the frequency change is consistent with the deviation automatically clear (similar to formulas and temperature effects). Overvoltage feature excellent way connected with the film cassette body liquid film using original corrugated processing technology, the external pressure is increased to a certain value, then the liquid film can be in full contact with the body, silicone oil is no longer transmitted to the pressure sensor With the increase of the external force, so as to achieve the protective effect of the sensor. http://www.yihemeter.com