Considerations for selecting Rosemount transmitters

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Considerations for selecting Rosemount transmitters​ With the continuous advancement of industrial society, the industry of automated instruments and equipment, represented by Rosemount transmitters, has also seen rapid development. In today’s instrumentation market, pressure transmitters are being used more and more by various industries. Based on years of experience in this market, the Rosemount series of transmitters is very popular among industry professionals, as it not only requires no calibration over a period of ten years but also boasts many high-performance features. However, this is due to reasons such as the working environment, the medium, and the medium temperature. Therefore, we must take these issues into consideration when choosing Rosemount transmitters. Now I’ll talk about the considerations that need to be taken into account when selecting Rosemount transmitters 　　First, we need to consider the material in contact with liquid for the Rosemount transmitter. The material used for the contact medium part of standard pressure transmitters is 316 stainless steel. If the medium being measured by the pressure transmitter is not corrosive to 316 stainless steel, then basically all pressure transmitters are suitable for measuring the pressure of such a medium. 　　However, if the medium being measured is corrosive to 316 stainless steel, then in order to protect the pressure transmitter and extend its lifespan, we need to use Rosemount transmitters with chemical seals. This not only allows for the measurement of the pressure of the medium but also effectively prevents the medium from coming into contact with the parts of the pressure transmitter that are in contact with the fluid. 　　Second, Rosemount transmitters have a high level of accuracy, so the accuracy grade needs to be taken into consideration when making a choice. Every electronic measuring instrument has precision errors, but since the specified accuracy levels vary, we need to choose Rosemount transmitters based on the requirements of different applications. For example, in the part of the range where the transmitter exhibits the best linearity, this is the case in countries such as China and the United States; the **target accuracy is usually within a range of 10% to 90%** ； The part with the worst linearity is the accuracy of European benchmarks, which typically ranges from 0 to 10% and from 90% to 100% in terms of accuracy. If the precision for European targets is 1%, then it is 0.5% for Chinese targets. Therefore, when making a choice, we must consider the application scenario to determine which standard transmitter is appropriate, and whether a high-precision Rosemount transmitter is needed. 　　Third, the consideration of the range of Rosemount transmitters. Generally, it is best for Rosemount transmitters to measure up to 70% of their full scale. So, for example, if we need to measure a pressure of 70 bar, we should choose a pressure transmitter with a range of 100 bar. 　　Fourth, considerations regarding the output signal. To meet various data acquisition requirements, there are many different output signals for pressure transmitters available on the market, with the main ones being 4-20mA, 0-10V, 0-20mA, 0-5V, and so on. But the first two are more commonly used. 　　Fifth, the consideration of medium temperature. Under normal circumstances, the temperature of the medium measured by a pressure transmitter ranges from -30 to +100 degrees. However, since the signal from the pressure transmitter is converted through electronic circuits, when the temperature is too high, Rosemount transmitters that use a condensation elbow to cool the medium are typically used. This approach reduces the cost associated with having the manufacturer produce a pressure transmitter designed to withstand high temperatures. 　　Sixth, the measuring medium. Generally, when we measure relatively clean fluids, we can simply use standard Rosemount pressure transmitters. However, when the fluid to be measured is crystalline or viscous, in order to prevent it from blocking the pressure measurement ports, we usually use transmitters with external diaphragms or combine them with chemical seals. 　　Seventh, others. Furthermore, we cannot overlook the process connection interface of the Rosemount transmitter as well as the supply voltage for the pressure transmitter ； For use in special situations, Rosemount transmitters with explosion protection and protection ratings should also be considered.