The **ISCNH90P** is a high-precision, industrial-grade current sensor (transducer) typically based on **Hall Effect** technology or **Closed-Loop (compensated)** technology. It is designed to measure DC, AC, and pulsed currents with galvanic isolation between the primary high-power circuit and the secondary electronic circuit. --- ### 1. Key Technical Specifications The following table summarizes the typical electronic characteristics of this series: | Parameter | Specification (Typical) | | :--- | :--- | | **Nominal Current ($I_{pn}$)** | 90A (Root Mean Square) | | **Measuring Range** | Up to ±150A ~ ±270A (Peak) | | **Supply Voltage ($V_c$)** | ±12V to ±15V DC (Dual Supply) | | **Output Signal** | Current Output (Secondary current $I_s$) | | **Conversion Ratio** | 1:1000 or 1:2000 (depending on specific revision) | | **Accuracy** | ±0.5% at $T_a = 25^\circ C$ | | **Frequency Bandwidth** | DC to 100 kHz or 200 kHz | --- ### 2. Core Electronic Components & Architecture The device consists of several internal electronic stages that allow for non-contact current measurement: #### A. Magnetic Core A ring or square-shaped core made of high-permeability soft magnetic material. The primary conductor passes through the center, creating a magnetic field proportional to the current flow. #### B. Hall Effect Element Located in the air gap of the magnetic core. This semiconductor sensor detects the magnetic flux density and converts it into a small millivolt signal. #### C. Compensation Circuit (Closed-Loop) Unlike basic sensors, the "P" series usually employs a **Closed-Loop** architecture: 1. The Hall element detects the primary field. 2. An internal **Operational Amplifier** drives a "compensation current" through a secondary coil wound around the core. 3. This secondary current creates an opposing magnetic field that cancels out the primary field (maintaining zero flux). 4. **Benefit:** This results in high linearity and very low temperature drift. #### D. Termination Resistor ($R_m$) To read the output, the secondary current flows through an external measuring resistor ($R_m$) to ground. The voltage across this resistor represents the measured current. --- ### 3. Connection Pinout Typically, the ISCNH90P features a 3 or 4-pin PCB mounting configuration: 1. **+V**: Positive Power Supply (+12V to +15V). 2. **-V**: Negative Power Supply (-12V to -15V). 3. **M (or Out)**: Measurement Output terminal. 4. **0V (or Gnd)**: Reference ground for the power supply. --- ### 4. Applications * **Variable Speed Drives (VFDs):** Monitoring motor phase currents. * **Uninterruptible Power Supplies (UPS):** Battery charging and inverter output monitoring. * **Solar Inverters:** Tracking DC input from PV strings. * **Welding Equipment:** Precision control of high-current output.