Operating Principle

The LDE-EX-DN100 explosion-proof electromagnetic flowmeter operates based on Faraday's law of electromagnetic induction. When a conductive liquid flows through the magnetic field inside the sensor, an induced electromotive force (EMF) proportional to the flow velocity is generated. The voltage detected by the electrodes is amplified, filtered, and linearized by the converter, then converted into standard current or frequency signals for output. The measurement is unaffected by fluid temperature, pressure, density, or viscosity, relying only on average velocity.

Construction Features

The sensor features a fully welded structure with PTFE or polyurethane lining for corrosion resistance. Electrodes are made of Hastelloy C-276 or tantalum. The converter is housed in a flameproof enclosure with potted circuits, meeting Ex d ib ⅡB T4 explosion protection. The housing is cast aluminum alloy or stainless steel, rated IP68. The sensor and converter can be integrated or remote-mounted (up to 100 meters apart).

Technical Advantages

• No moving parts: minimal pressure loss, reducing pump energy consumption.
• High accuracy: ±0.5% of reading, repeatability ≤0.1%, suitable for custody transfer.
• Wide turndown: standard 20:1, optional 50:1, adapting to flow fluctuations.
• Bidirectional measurement: forward/reverse flow without additional configuration.
• Intelligent self-diagnosis: real-time monitoring of electrode fouling, empty pipe, excitation open circuit, etc.
• Multiple outputs: 4-20mA HART, pulse, RS485 Modbus for easy integration.