HMSR 30-SMS – LEM Next-Generation High-Insulation Integrated Current Sensor

HMSR 30-SMS Product Overview

The HMSR 30-SMS is a next-generation, high-insulation integrated current sensor from LEM’s HMSR-SMS series. It uses a micro-core open-loop Hall effect technology, providing a robust, compact, high-accuracy AC/DC current measurement solution for demanding switching power supply applications. Whether your application is commercial or industrial, the HMSR 30-SMS is up to the task.

The product is available through major distributors worldwide, including element14 and DigiKey. At LCSC, prices start as low as CNY 13.54 (volume discounts available). The standard SOIC package supports SMT assembly for fast, high-volume production.

HMSR 30-SMS Key Performance Specifications

The HMSR 30-SMS operates from a single +5V supply with very low power consumption (max 26mA), allowing seamless integration with most MCU systems and greatly simplifying power supply design.

HMSR 30-SMS Core Advantages

1. High Accuracy & Reinforced Insulation – Safe and Reliable

The HMSR 30-SMS complies with international safety standards including IEC 61800-5-1:2007, IEC 62109-1:2010, and IEC 60950-1:2005. It features reinforced insulation (4.95kVRMS insulation test voltage) with galvanic isolation between primary and secondary sides, ensuring system safety. The chip height is only 6mm, making it easy to install in space-constrained equipment.

2. Excellent Surge Withstanding Capability

The integrated primary conductor has very low resistance, and the specially designed pads can withstand surge currents up to 20kA (8-20µs waveform) – a lightning-level overload capacity. Even in harsh industrial power environments, the HMSR 30-SMS reliably handles electrical surges, protecting your equipment from damage.

3. Dual Overcurrent Detection (OCD) – Double System Safety

The HMSR 30-SMS provides two overcurrent detection outputs (user-configurable or factory-preset), enabling hardware-level fast overcurrent protection. When the current exceeds the set threshold, the protection is triggered immediately without relying on software response, offering dual safety protection for your system.

4. High Immunity to External Interference

Thanks to advanced micro-core technology and an optimised magnetic design, the HMSR 30-SMS has excellent immunity to stray magnetic fields. Even in complex electromagnetic environments (e.g., near variable-frequency drives or inside high-power switching power supplies), it delivers stable and accurate measurement signals, avoiding false readings caused by interference.

HMSR 30-SMS Typical Applications

The HMSR 30-SMS is ideal for a wide range of commercial and industrial switching power supply applications, including:

✅ Small Motor Drives

Real-time motor current monitoring for precise torque control and overload protection.

✅ Appliance Frequency Converters

Current sensing in variable-frequency drives for air conditioners, washing machines, refrigerators, etc., improving energy efficiency.

✅ Solar Inverters

A key current sensing component in photovoltaic inverters, supporting efficient renewable energy systems.

✅ HVAC Systems

Current monitoring and energy management for commercial and residential heating, ventilation, and air conditioning equipment.

✅ Photovoltaic Systems

Accurate current monitoring in renewable energy installations.

✅ Other High-Frequency Switching Power Supply Applications

Including lighting equipment, electric curtains, UPS systems, and many other industrial and commercial scenarios.