HMSR 30-SMS current transducer

HMSR is a next-generation, high-isolation integrated current sensor from LEM. This product family offers a robust, compact, and exceptionally precise solution for measuring both direct (DC) and alternating (AC) currents in demanding switched-mode power applications used in commercial and industrial sectors.

HMSR is an open-loop sensor based on a micro magnetic core, featuring reinforced insulation and an overcurrent detection function (configurable by the user or factory-set). These characteristics make it suitable for high-voltage applications requiring high precision and strong resistance to external interference fields. The primary conductor (pins 1 and 8) is designed with ultra-low electrical resistance and specially engineered pads that withstand high-amplitude current surges, such as lightning strikes.

HMSR measures the magnetic field generated by the current flowing through the copper track of the primary conductor. Thanks to the micro magnetic core, the sensor exhibits high immunity to external interference fields, making it ideal for power electronics applications exposed to strong electromagnetic disturbances. The reinforced insulation between the primary circuit (pins 1 and 8) and the secondary circuit (pins 9 to 15) makes HMSR a compact and cost-effective high-side current measurement solution compared to resistive solutions requiring galvanic isolation.

Main features

• Multi-range open-loop current transducer
• Voltage output
• Dual overcurrent detection
• Single +5V power supply
• Galvanic isolation between primary and secondary circuits
• Low power consumption
• Compact design for SMT mounting
• Factory-calibrated
• Wide bandwidth, ultra-low-loss magnetic core
• Low profile: h=6mm
• Small footprint
• Low electrical resistance 0.76mΩ
• Reinforced insulation
• High resolution
• High resistance to external interference
• Lightning surge current ≤ 20kA

Applications

• Small drives
• HVAC inverters
• Appliances
• Solar inverters

Technical data