How to select a transmitter ？

      （Explanation of model, structure and material.）

A compact pressure transmitter (in English: Compact Pressure Transmitter) is a miniaturized device that converts the measured pressure signal (such as gas or liquid pressure) into standardized electrical signals (such as 4-20mA, 0-5V, etc.) for easier transmission, display or control. Its features include small size, light weight, convenient installation, and suitability for applications with limited space (such as within compact equipment, portable instruments or micro industrial systems).  

1. The key to determining the model lies in the parameters.                    
The model numbers of compact pressure transmitters are usually a combination of letters and numbers. The coding rules vary slightly among different manufacturers, but the core parameters are generally the same. By considering these points, you can quickly match the requirements:                    
·YSZC: Represents the product series, indicating that it belongs to a specific compact pressure transmitter series. It could be a code, letter, or internal numbering rule set by the manufacturer, or it could represent that it possesses some common characteristics.                    
·Pressure range: Marked directly with numbers. Common units include MPa, KPa, and bar. For example, 0-1 MPa indicates that the measurement range is 0 to 1 megapascal.                    
·Output signal: Commonly used in industry is "4-20mA" (analog signal), and RS485 (digital signal, often paired with Modbus protocol). The model may indicate it as "420" or "RS485".                    
·Accuracy grade: It is indicated by numbers or letters. For example, "0.25" represents an accuracy of 0.25 grade, and "0.5" is a 0.5 grade. The higher the accuracy, the smaller the measurement error.                    
                    
2，The three core components determine the performance.                    
The compact pressure transmitter is small in size but has a compact structure and complete functions. It is mainly composed of three core parts:                    
·Pressure sensing element (core sensing unit): In direct contact with the measured medium, it converts pressure signals into tiny electrical signals. The mainstream types include "diffused silicon sensor" (high accuracy, fast response, suitable for conventional industrial scenarios) and "ceramic sensor" (resistant to corrosion, anti-pollution, suitable for harsh media such as acids and alkalis).                    
·Signal processing module: Receives the tiny signals from the pressure sensing element, and through amplification, filtering, and linearization processing, converts them into standard output signals (such as 4-20mA). This part determines the stability and anti-interference ability of the transmitter.                    
·Case and Interface: The shell serves as a protective and sealing component, while the interface is used for connecting the tested pipeline/equipment. Common protection levels include IP65 (dustproof and splashproof) and IP67 (dustproof and waterproof immersion). The connection types include M20*1.5 thread (standard), G1/4 thread (imperial), etc.    

              
3,The material determines the measurement outcome.                    
Pressure sensing diaphragm: In direct contact with the medium, it is a key factor in material selection.                    
·316L stainless steel: Resistant to corrosion, with high strength, suitable for most scenarios such as water, oil, and common gases, and offers good value for money.                    
· Alloy C: Resistant to strong corrosive agents (such as hydrochloric acid and sulfuric acid), suitable for harsh environments in industries like chemical and metallurgy.                    
·Tantalum sheet: Resistant to strong acids (especially hydrofluoric acid), with high cost, and is only used in special circumstances.                    
·Ceramics: Resistant to acids and alkalis, without static electricity, suitable for hygiene-level applications such as food and medicine (avoiding metal contamination).                    
Case material                    
Mostly made of die-cast aluminum alloy (with surface powder coating, lightweight, low cost) or stainless steel (resistant to corrosion, high temperature, suitable for outdoor and humid environments).                    
                    
Sealing material                    
Commonly used materials include nitrile rubber (resistant to oil, suitable for normal temperatures), fluorine rubber (resistant to both high and low temperatures, resistant to strong corrosion, suitable for extreme conditions), and silicone rubber (food grade, suitable for hygiene scenarios).                    

4,How to Choose the Right Transmitter: 3 Key Tips                    
·Focus on medium first: For corrosive media, limited options include Hastelloy alloys, ceramic diaphragms, and for sanitary applications, ceramics and silicone rubber seals are chosen.                    
·Focus on working condition second :For high-temperature environments, a stainless steel casing and fluorine rubber sealing are selected. In confined spaces, the length of the transmitter (usually ≤ 100mm) is confirmed.                    
·Finally, consider the requirements：The precision requirement is for a 0.25-grade diffusion silicon sensor. Additionally, remote communication is needed and RS485 output should be selected.                    
                    
Summary：                    
Although the compact pressure transmitter is small in size, choosing the right model, structure and material is essential to ensure its significant role in industrial measurement. If you have any specific doubts about the selection based on the working conditions, please feel free to leave a comment in the discussion area for further discussion!