There are many differences between pressure transmitters and ordinary pressure gauges. The following is a detailed introduction:

Functional purpose

Pressure transmitter: mainly used to convert pressure signals into standard electrical signals (such as 4-20mA, 0-10V, etc.) for output, facilitating transmission and subsequent processing. It is often used in conjunction with control systems, data acquisition systems, etc. to achieve remote monitoring and control of pressure, and is widely used in industrial automation, process control, and other fields. For example, in chemical production, pressure transmitters can transmit real-time pressure signals inside pipelines to the control system, ensuring the safety and stability of the production process.

Ordinary pressure gauge: mainly used for directly displaying pressure values on site, allowing operators to intuitively understand the pressure situation. It is generally installed on equipment or pipelines for easy on-site observation and is suitable for situations where pressure measurement accuracy is not required. For example, ordinary pressure gauges installed on small boilers can allow operators to constantly monitor the pressure conditions inside the boiler.

measuring principle

Pressure transmitter: Common measurement principles include capacitive, diffused silicon, piezoresistive, etc. Taking capacitance as an example, when pressure is applied to sensitive components, it will cause a change in capacitance value. The magnitude of pressure can be determined by measuring the change in capacitance value. The diffusion silicon method utilizes the piezoresistive effect of silicon, where pressure changes cause a change in the resistance of the diffused silicon, thereby measuring the pressure.

Ordinary pressure gauges: mostly measure pressure based on the deformation of elastic components such as spring tubes, diaphragms, bellows, etc. When pressure is applied to the elastic element, it undergoes corresponding deformation, which is transmitted to the pointer through the transmission mechanism, and the pointer indicates the pressure value on the dial. For example, in a spring tube pressure gauge, the spring tube will expand or contract under pressure, driving the pointer to rotate.

Output

Pressure transmitter: The output is a standard electrical signal, which is convenient for long-distance transmission and connection with other devices. The type and range of output signals are usually fixed, such as 4-20mA or 0-10V, and can be directly connected to automation control systems or data acquisition devices.

Ordinary pressure gauge: presents pressure values in the form of mechanical pointer indication or numerical display, without electrical signal output, and cannot directly transmit and control data with other devices.

accuracy class

Pressure transmitter: The accuracy is relatively high, generally up to 0.1% FS, 0.25% FS, 0.5% FS, etc. (FS represents full range), suitable for occasions with high requirements for pressure measurement accuracy.

Ordinary pressure gauge: The accuracy level is relatively low, commonly including 1.0 level, 1.6 level, 2.5 level, etc., which can meet the pressure measurement needs of general industrial production and daily life.

Structural characteristics

Pressure transmitter: The structure is relatively complex, including sensitive components, signal processing circuits, housing, and other parts. In order to adapt to different work environments and measurement requirements, protective devices, isolation devices, etc. may also be equipped.

Ordinary pressure gauge: The structure is relatively simple, mainly composed of elastic elements, transmission mechanism, pointer, and dial. Its shell is usually made of metal or plastic material, which has a certain degree of protective ability.

Price cost

Pressure transmitter: Due to its signal conversion and output functions, as well as high accuracy, the price is relatively high.

Ordinary pressure gauge: simple structure, single function, relatively low price, suitable for occasions with high cost control requirements.