The **HAS-41-R** is a high-precision, hall-effect current sensor manufactured by **LEM**. It is designed for electronic measurement of currents (DC, AC, pulsed, and mixed) with galvanic separation between the primary circuit and the secondary circuit. --- ### ## Technical Specifications The following table outlines the key electrical and physical characteristics of the HAS-41-R sensor: | Parameter | Specification | | :--- | :--- | | **Nominal Current ($I_{PN}$)** | 400 A | | **Measuring Range ($I_{PM}$)** | ± 900 A | | **Supply Voltage ($V_C$)** | ± 15 V (± 5%) | | **Secondary Output Voltage** | ± 4 V (at $I_{PN}$) | | **Accuracy** | ± 1% of $I_{PN}$ | | **Linearity** | < 1% | | **Frequency Bandwidth** | DC ... 50 kHz | | **Operating Temperature** | -10°C to +80°C | --- ### ### Key Electronic Components & Features 1. **Hall Effect Transducer:** The core of the device is a Hall Effect sensor placed in the gap of a magnetic core. When current flows through the primary conductor, it creates a magnetic field that the Hall element converts into a proportional voltage. 2. **Open Loop Architecture:** Unlike closed-loop (compensation) sensors, the HAS-41-R uses **Open Loop technology**. This makes it more cost-effective and energy-efficient, though it typically has a slightly lower bandwidth than closed-loop alternatives. 3. **Galvanic Isolation:** The sensor provides high electrical isolation (typically up to 3000V) between the high-power primary busbar and the low-voltage control electronics. 4. **Signal Conditioning Circuitry:** Internal op-amps and resistors scale the raw Hall voltage to a standardized $\pm 4V$ output, ensuring it is ready for input into an Analog-to-Digital Converter (ADC) or a microcontroller. --- ### ### Typical Connection Interface The secondary side (output) usually features a 4-pin connector: | Pin Number | Designation | Function | | :--- | :--- | :--- | | 1 | $+V_C$ | Positive Supply (+15V) | | 2 | $-V_C$ | Negative Supply (-15V) | | 3 | $V_{OUT}$ | Output Signal (± 4V) | | 4 | $0V$ | Ground / Reference | --- ### ### Applications * **Variable Speed Drives (VFDs):** Monitoring motor current. * **Uninterruptible Power Supplies (UPS):** Battery charging and load monitoring. * **Solar Inverters:** Tracking DC input and AC output currents. * **Welding Equipment:** High current DC control.