The **AS4V-S25-R/Q** is a high-precision, industrial-grade current sensor (transducer) typically used for monitoring electrical systems. It operates based on the **Hall Effect** principle or **Fluxgate technology** to measure DC, AC, and pulsed currents with galvanic isolation. --- ### 1. Key Technical Specifications | Feature | Specification | | :--- | :--- | | **Primary Nominal Current ($I_{pn}$)** | 25A | | **Measuring Range** | Up to ±80A (depending on burden resistor) | | **Supply Voltage ($V_c$)** | ±12V to ±15V (Dual supply) | | **Output Type** | Current Output (Secondary current $I_s$) | | **Conversion Ratio** | 1:1000 | | **Accuracy** | ±0.5% at room temperature | | **Isolation Voltage** | 3kV - 6kV AC (50Hz, 1 min) | --- ### 2. Internal Electronic Components The device consists of several critical electronic sub-systems integrated into a single module: 1. **Magnetic Core:** A high-permeability toroidal core that concentrates the magnetic flux generated by the primary conductor passing through the center hole. 2. **Compensation Winding:** A secondary coil wrapped around the core. This sensor uses **Closed-Loop (Zero Flux)** technology, where an internal circuit drives current through this winding to cancel out the magnetic field of the primary current. 3. **Hall Element / ASIC:** A sensing element located in the air gap of the core that detects the magnetic null point. 4. **Operational Amplifier:** A high-gain amplifier that processes the signal from the Hall element and drives the secondary compensation current. 5. **Protection Diodes:** Internal circuitry to prevent damage from reverse polarity or voltage spikes. --- ### 3. Pinout and Connection Logic The "R/Q" variants usually refer to the physical mounting style (PCB Pins or Faston terminals). | Pin/Terminal | Function | Description | | :--- | :--- | :--- | | **+V** | Positive Supply | Connect to +12V or +15V DC | | **-V** | Negative Supply | Connect to -12V or -15V DC | | **M** | Measurement | Output signal current; connected to a burden resistor ($R_m$) to ground | | **0V** | Common | Reference ground | --- ### 4. Application Use Cases * **Variable Speed Drives:** Monitoring motor current for precise control. * **Uninterruptible Power Supplies (UPS):** Managing battery charging and load distribution. * **Solar Inverters:** Tracking DC input from panels and AC output to the grid. * **Welding Equipment:** Controlling the high-current output of industrial welders. ---