Which port is used to interface the output signal of the electromagnetic flowmeter?

　　1、 Introduce electromagnetic flowmeter

　　Electromagnetic flowmeter is a flow measurement instrument applied in the field of industrial automation control, which can usually directly measure the flow of various conductive liquids and solid suspensions. It utilizes Faraday's law of electromagnetic induction to convert the electromotive force induced when a conductive medium cuts a magnetic field into standard analog and digital quantities through a converter. Among them, the output signal can be interface through various ports, including 4-20mA, RS485, HART, pulse, etc.

　　2、 Output signal interface of electromagnetic flowmeter

　　1. 4-20mA external centralized converter

　　This interface is the most widely used output signal interface in the electromagnetic flowmeter industry. Its electronic circuit is simple, the transmission distance can be long, and it can be used at multiple points to avoid interference between instruments and acquisition instruments. It should be noted that polarity should be taken into account when interfacing.

　　2. RS485

　　This interface has the characteristics of fast transmission speed and strong anti-interference ability, and can be applied in harsh electromagnetic environments. In large-scale monitoring systems, the RS-485 bus adopts a hierarchical structure, which can establish multi-level networks and facilitate data communication. But it does not come with a built-in power supply and needs to be connected to a separate power source.

　　3. HART

　　The interface of the HART protocol is to add a HART digital communication protocol in addition to the 4-20mA interface. It uses 4-20mA output signals for digital communication applications, organically combining analog signals with digital communication. It has the advantages of stable performance and easy installation.

　　4. Pulse

　　This interface can output frequency signals or pulse signals, and the magnitude of the signal impulse depends on the range of the electromagnetic flowmeter. Its application range is relatively small, and it is usually suitable for field production automation control and small flow measurement.

　　3、 Precautions

　　Before wiring, please confirm the signal type of the electromagnetic flowmeter, as different methods have different wiring methods.

　　When wiring, it is necessary to pay attention to the positive and negative polarity of the interface and prevent interference with the signal and power lines.

　　3. When using multiple electromagnetic flow meters, please confirm the usage of the input interface and the setting of the multiplication factor to prevent errors.

　　If you use it on site, you should choose cables that meet the requirements according to different interfaces and usage environments to prevent interference.

　　Summary: Different interfaces are suitable for different situations. Generally, it is recommended to choose commonly used 4-20mA and RS485. In practical application, it is necessary to choose and use according to different places and usage environments. When using, it is necessary to operate according to the equipment's user manual to ensure the normal use of the equipment.