LT505-T/SP22 – High-Precision Closed-Loop Hall Effect Current Sensor

Accurate measurement, stable and reliable. LEM’s 500A closed-loop Hall effect current sensor delivers an excellent solution for industrial and energy applications.

LT505-T/SP22 Product Overview

The LT505-T/SP22 is a high-performance closed-loop Hall effect current sensor from LEM (Switzerland). It has a rated primary current of 500A and an extended measuring range up to ±1200A. Designed for high-precision isolated measurement of DC, AC, and pulsed currents, it is widely used in motor drives, switching power supplies, renewable energy, and welding equipment.

As a global leader in electrical measurement transducers with over 50 years of technological expertise and deep ASIC design capabilities, LEM continues to provide accurate and reliable electrical measurement solutions. The LT505-T/SP22 fully demonstrates LEM’s commitment to precision, stability, and reliability.

LT505-T/SP22 Key Technical Specifications

Why Choose the LT505-T/SP22?

Closed-Loop Hall Effect Technology for Excellent Accuracy

The closed-loop (compensated) Hall effect technology uses a magnetic compensation principle to actively cancel the magnetic field generated by the primary current, keeping the sensor in a zero-flux state. This design provides ±0.6% accuracy and ±0.1% linearity – significantly better than conventional open-loop solutions.

Electrical Isolation for Safety & Reliability

Complete electrical isolation between the primary circuit (high-power side) and secondary circuit (electronic side) is achieved, with an isolation test voltage of 12,000V. This effectively protects sensitive downstream electronics while ensuring safety for operators and systems.

Microsecond Response for Real-Time Monitoring

With an ultra-fast response time of 1 μs and a 150 kHz bandwidth, the sensor can accurately capture rapidly changing transient current signals, meeting the real-time monitoring demands of high-performance variable frequency drives and switching power supplies.

High Overcurrent Capability

Beyond the rated ±500A, the sensor can measure peak currents up to ±1200A, easily handling inrush currents during motor starts, load changes, or other transient events without measurement distortion.

Stable Operation Across a Wide Temperature Range

The sensor operates reliably in harsh ambient temperatures from -10°C to +85°C, making it suitable for outdoor electrical cabinets, industrial sites, and other challenging environments.

Easy Integration with Panel Mounting

Designed for panel mounting with screw terminals on the primary side, it can be quickly integrated into electrical control systems and distribution cabinets. The compact modular design saves installation space and improves system integration efficiency.

LT505-T/SP22 Typical Applications

AC Variable Frequency Drives & Servo Motor Drives

Precisely monitor motor operating current, optimize motor control strategies, and enable energy efficiency improvements and fault prediction.

Static Converters for DC Motor Drives

Real-time capture of DC side current changes, providing accurate closed-loop feedback signals for motor control.

Battery-Powered Systems

Accurately track battery charge/discharge current, providing critical SOC (State of Charge) data for battery management systems.

Uninterruptible Power Supplies (UPS)

Monitor input and output currents to ensure stable power delivery during voltage fluctuations or outages, protecting critical loads.

Switch Mode Power Supplies (SMPS)

Precisely measure high-frequency switching currents, helping optimize power supply design and efficiency.

Welding Equipment Power Supplies

Withstand pulsed high currents in welding applications, providing real-time current feedback for consistent welding quality.

Renewable Energy Systems (Solar / Wind)

Track inverter input and output currents, enabling real-time monitoring and optimization of generation efficiency.

LT505-T/SP22 Brand Advantages

Since 1972, the LEM Group has focused on electrical transducers, with four major production sites in Beijing, Geneva, Tokyo, and Sofia, and a sales network covering key countries and regions. LEM products are widely used in industrial, rail, energy, automation, and automotive sectors. LEM sensors are renowned for high accuracy, reliability, and strict quality standards – making them a trusted partner for engineers in power electronics.