The **W2SP-2D2-R** is a specific model within a series of industrial **Electromagnetic Flowmeters**, typically associated with manufacturers like **Azbil (formerly Yamatake)**. These devices are used to measure the flow rate of conductive liquids in industrial piping. --- ### 1. General Specifications The model string identifies specific electronic and physical characteristics. Below is a breakdown of the typical electronic parts and parameters associated with this unit: | Component | Specification / Value | | :--- | :--- | | **Measurement Principle** | Faraday’s Law of Electromagnetic Induction | | **Excitation Method** | Square-wave excitation (Low frequency) | | **Input Power** | 100 to 240V AC (Standard) or 24V DC (Optional) | | **Output Signal** | 4-20 mA DC (Current Loop) | | **Pulse Output** | Open Collector (for totalizing flow) | | **Communication** | DE (Digital Enhanced) or HART Protocol | --- ### 2. Core Electronic Components The internal electronics are generally divided into two main modules: the **Sensor (Primary)** and the **Converter (Secondary)**. #### A. The Converter Unit This is the "brain" of the device. It contains: * **Signal Processing Board:** Converts the microvolt signals from the electrodes into a digital value. It uses high-impedance amplifiers to prevent signal loading. * **Excitation Circuit:** Provides the current to the coils inside the flow tube to generate the magnetic field. * **LCD Display:** A local interface to show instantaneous flow rate, flow velocity, and totalized volume. * **I/O Terminals:** Where the 4-20mA, pulse, and power wiring are connected. #### B. The Sensor Unit (Electrodes & Coils) * **Electrodes:** Usually two stainless steel or Hastelloy pins that come into contact with the fluid. They pick up the induced voltage. * **Excitation Coils:** Copper windings located outside the flow tube but inside the housing, used to create the magnetic field. * **Lining:** While not "electronic," the insulating liner (e.g., PFA or Rubber) is critical to prevent the signal from shorting to the metal pipe. --- ### 3. Wiring Configuration For the W2SP series, the electronic wiring usually follows this standard terminal layout: | Terminal Label | Function | Description | | :--- | :--- | :--- | | **L / N** | Power Supply | AC Mains or DC Power Input | | **I+ / I-** | Analog Output | 4-20mA Flow Rate Signal | | **P+ / P-** | Pulse Output | Scaled pulse for remote counters | | **GND** | Grounding | Protective earth and functional ground | --- ### 4. Key Electronic Features * **Empty Pipe Detection:** The electronics monitor electrode impedance. If the pipe is empty, the output is driven to a specific value (e.g., 0% or 110%) to prevent false readings. * **Bidirectional Flow:** The electronics can distinguish between forward and reverse flow based on the phase of the induced voltage. * **Noise Filtering:** Uses digital signal processing (DSP) to filter out electrochemical noise and slurry noise. ---