LTC 500-SF/SP7 , LTC500-SF/SP7

LEM LTC 500-SF/SP7 LTC Series Closed Loop Current Transducer

LEM LTC 500-SF/SP7 Product Overview

The LTC 500-SF/SP7 is a closed-loop Hall effect current transducer from LEM's LTC350-500 Series, designed for the electronic measurement of DC, AC, and pulsed currents with galvanic separation between the primary circuit and the secondary circuit . This modular panel-mount transducer features a 27.5 mm diameter aperture for primary conductor installation and includes pre-mounted feet for simplified mounting in railway traction applications .

Rated for 500 A nominal with a measuring range of ±1200 A, it outputs a secondary current of 125 mA at nominal with ±0.6% total accuracy and <0.1% linearity . The turns ratio is 1:4000. Response time is <1 µs and frequency bandwidth is DC to 100 kHz . Supply voltage range is ±15 V to ±24 V DC. Mass is 410 g and operating temperature ranges from -40°C to +85°C . Insulation test voltage is 12 kV RMS at 50 Hz for 1 minute, with 44 mm creepage distance and 43 mm clearance . The device meets EN 50155:2017 and EN 50121-3-2:2016 railway standards .

LEM LTC 500-SF/SP7 Key Specifications

LEM LTC 500-SF/SP7 Key Advantages

The LTC 500-SF/SP7 employs closed-loop Hall effect technology with an insulating plastic case recognized according to UL 94-V0, delivering ±0.6% accuracy and <0.1% linearity while providing galvanic isolation between primary and secondary circuits . The 27.5 mm aperture enables non-intrusive installation of primary conductors without disconnecting existing cables. The ±1200 A measuring range accommodates significant overload conditions, while the <1 µs response time and 100 kHz bandwidth capture dynamic current signals in traction applications . The wide -40°C to +85°C operating temperature range ensures reliable performance in harsh railway environments . The Molex Mini-Fit.Jr. connector provides a secure and reliable secondary connection interface . The pre-mounted feet support flexible horizontal or vertical mounting options, and a standard shield provides immunity to external interference . The design offers excellent accuracy, very good linearity, low temperature drift, optimized response time, and no insertion losses .

LEM LTC 500-SF/SP7 Typical Applications

Single or three phase inverters for railway traction
Propulsion and braking choppers
Propulsion converters for trains and locomotives
Auxiliary converters for onboard power supply
Battery chargers for railway rolling stock
Railway fixed installations and trackside equipment
Overcurrent protection and fault detection in traction systems
Circuit breakers for railway infrastructure

Why Choose the LEM LTC 500-SF/SP7?

The LTC 500-SF/SP7 combines a 500 A rated current and ±1200 A measuring range with a 125 mA closed-loop current output in a robust panel-mount package with 27.5 mm aperture, pre-mounted feet, and Molex Mini-Fit.Jr. connector. Manufactured by LEM, it delivers stable, accurate, and safe current measurement specifically for railway traction applications. The closed-loop Hall effect design provides exceptional accuracy and linearity with low temperature drift, while the integral aperture and modular design simplify installation and system integration. Compliance with EN 50155:2017 railway standards ensures reliable operation in demanding rail environments, making it an ideal choice for propulsion, braking, and auxiliary converter systems .