Overview
LEM current sensors are world-leading current measurement solutions, leveraging Hall effect and fluxgate technologies to achieve high-precision, contactless current detection. This article systematically explains the technical characteristics, model classification, performance parameters, and application areas of LEM current sensors, and provides an in-depth analysis of their operating principles, structural design, and performance advantages. LEM current sensors feature high accuracy, wide bandwidth, strong isolation, and excellent temperature characteristics. They are widely used in industrial drives, renewable energy generation, rail transit, and smart grids, providing reliable current measurement and protection for modern power electronics systems.
1.The main Technical Characteristics and Performance Advantages Of LEM Current Sensors
LEM current sensors utilize advanced Hall effect and magnetic compensation technologies to achieve contactless current measurement, providing extremely high measurement accuracy and reliability. These LEM current sensors exhibit extremely low temperature drift, maintaining stable measurement performance across the entire operating temperature range, ensuring long-term accuracy. LEM current sensors utilize a closed-loop compensation principle, generating a reverse magnetic field in the secondary coil to achieve zero-flux detection. This design enables a wide measurement range and excellent linearity. LEM current sensors also offer electrical isolation up to 6000V, effectively protecting low-voltage measurement circuits from interference from high-voltage sources. These LEM current sensors exhibit excellent electromagnetic compatibility and operate reliably in harsh industrial environments. Modern LEM current sensors also integrate intelligent features such as overcurrent detection and fault alarms, providing stronger user safety. These superior features make LEM current sensors the preferred solution for high-precision current measurement.
2. The Main Model Range Of LEM Current Sensors
LEM current sensors are divided into multiple product series based on measurement principles and application requirements. The LA series is a classic open-loop Hall effect sensor. Its open-loop design facilitates installation and is suitable for industrial frequency conversion and power supply equipment. The LT series is a closed-loop zero-flux current sensor, offering higher accuracy and faster response time, making it suitable for demanding of servo control systems. The LK series is an economical LEM current sensor, offering competitive pricing while maintaining essential performance. The DH series is a high-frequency response LEM current sensor with a bandwidth exceeding 200kHz, suitable for switching power supplies and high-frequency inverters. The HMS series is a miniaturized LEM current sensor featuring a space-saving SMD package, suitable for high-density PCB designs. There is also a series of LEM current sensors specifically designed for new energy vehicles, meeting automotive-grade reliability requirements. These diverse LEM current sensor models provide users with a comprehensive selection.
3.Technical Parameters of LEM Current Sensors
The performance of LEM current sensors is reflected in a series of precise technical parameters that determine their application effectiveness. Measurement accuracy is a core parameter of LEM current sensors. High-end models achieve accuracies of ±0.2% or even better, meeting the most stringent measurement requirements. Bandwidth reflects the dynamic response capability of LEM current sensors, typically ranging from DC to 100kHz with some high-frequency models reaching 500kHz. Response time is another important parameter, with LEM current sensors typically offering a fast response time of less than 1μs. Rated currents range from a few amperes to several thousand amperes, allowing users to select the appropriate LEM current sensor based on their specific needs. Isolation voltage reflects their safety performance, with most LEM current sensors offering an operating isolation voltage exceeding 2000V. In terms of temperature characteristics, LEM current sensors operate normally over a wide temperature range of -40°C to +85°C. These combined advantages enable LEM current sensors to maintain stable and reliable performance in a variety of harsh environments.
4.The Main application Area Of LEM Current Sensors
LEM current sensors are widely used in numerous industrial fields due to their stable performance. In industrial automation, LEM current sensors are used in servo drives, robotic control systems, and PLC devices, providing accurate current feedback. In the new energy sector, LEM current sensors are widely applied in photovoltaic inverters, wind turbines, and energy storage systems enabling efficient energy conversion. In rail transit, LEM current sensors are used in traction converters, auxiliary power systems, and signaling equipment to ensure safe operation. Smart grid construction relies on LEM current sensors for power quality monitoring, fault detection, and protection control. In automotive electronics, LEM current sensors play a vital role in battery management systems, motor controllers, and charging equipment. Furthermore, LEM current sensors are widely used in high-end equipment such as uninterruptible power supplies, welding equipment, and medical instruments, and their reliability and accuracy are widely recognized in the industry.