LTC 350-SF , LTC350-SF

LTC 350-SF Closed-Loop Hall Effect Current Transducer

— Precision, Reliability, Wide-Temperature Current Guardian

LTC 350-SF Product Overview

The LTC 350-SF is a closed-loop Hall effect current transducer from LEM, a world leader in current sensing. Designed specifically for traction applications and industrial electrical systems, it accurately measures DC, AC, and pulsed currents up to a rated current of 350 A, with a wide measuring range up to 1200 A. It is widely used in power electronics, renewable energy, automotive electronics, and industrial automation.

In precision-controlled industrial environments, the accuracy of current measurement directly determines system stability and safety. The LTC 350-SF is more than just a transducer – it is the data bedrock of a reliable system, transforming invisible current changes into stable, traceable output signals, providing authentic “current language” for your control system.

LTC 350-SF Key Advantages

Wide measuring range – one unit for multiple applications

Rated current 350 A, maximum measurable current 1200 A, covering everything from light load to overload conditions. Even under low load, the transducer maintains high linearity and low error, never magnifying measurement errors – significantly reducing selection and inventory complexity.

Closed-loop Hall effect technology – precision and speed combined

Built on LEM’s mature closed-loop Hall effect technology, the transducer accurately tracks and reproduces the primary current under galvanic isolation. Accuracy ±0.5 %, linearity better than ±0.1 %, response time only 1 µs, and frequency bandwidth from DC to 100 kHz – capturing the full spectrum of current signals from steady state to transient events.

Modular mechanical design – flexible mounting for any installation

The LTC 350-SF features a compact modular design supporting horizontal or vertical mounting with multiple configuration options: selectable integrated busbar, and the base can be mounted in 3 different ways enabling 3 possible vertical mounting arrangements. The primary conductor opening is 27.5 mm in diameter, accommodating a wide range of cable gauges. Secondary connection offers two fastening modes: 4×M5 threaded studs or 4×Faston (6.3×0.8 mm), meeting diverse wiring habits and reliability requirements.

-40 ℃ to +85 ℃ wide-temperature operation – stable under any conditions

Operating temperature range -40 ℃ to +85 ℃ – the transducer remains stable in extreme cold or heat. Accuracy of ±0.5 % is maintained even at high temperatures, without drift-induced data distortion. One engineer, using the LTC 350-SF for continuous monitoring in a battery test application, saw no output fluctuation for 7 days and initially suspected a probe failure – that is the reality of outstanding temperature stability.

Multiple certifications – safe and reliable

The product holds numerous international approvals: ROHS3 compliant, UL94-VO rated materials, CE certified, and meets EN 50124-1 insulation class as well as NFF 16101/2 fire/smoke standards. 12 kV / 50 Hz insulation test voltage ensures safe isolation in high-voltage scenarios.

LTC 350-SF Technical Specifications

LTC 350-SF Typical Applications

The LTC 350-SF is well suited for a wide range of industrial and renewable energy applications, including:

PV inverters – accurate current monitoring of PV arrays

Energy storage PCS and BMS – precise charge/discharge current measurement and protection

EV electronic control systems – including traction battery, motor drive, brake-by-wire, ABS, and electronic stability control

SMPS and UPS – real-time input/output current monitoring for power supply safety

Servo drives and industrial VFDs – motor load current monitoring for optimised control

Traction systems and rail transport – meets EN 50155 traction application standards

Charging stations and fuel cell test systems – precise energy metering

Power semiconductor test and special power supplies – high-accuracy closed-loop current control

With its wide range and bidirectional measurement capability, the LTC 350-SF is especially suitable for DC energy storage systems that need to monitor both charging and discharging directions, as well as variable frequency drives that capture transient surge currents.

Why choose the LTC 350-SF?

In industrial automation, the stability and accuracy of the transducer define the ultimate quality of the system. Choosing the LTC 350-SF means you choose:

Trusted precision – closed-loop topology ensures high linearity and low offset over the full temperature range

Safe galvanic isolation – 12 kV insulation withstand voltage, protecting both system and personnel

Simple and efficient installation – modular design for flexible assembly, reducing inventory variants

Renowned brand – four decades of LEM sensing expertise, proven in hundreds of thousands of installations

Broad applicability – from PV plants to electric vehicles, industrial power supplies to energy storage systems