Founded in 2005 by a team of overseas-return engineers, Shanghai Freesor is a high-tech enterprise integrating design, R&D, production and sales under one roof. In June 2024 the company formally became a subsidiary of Keli Group, significantly enhancing its research capabilities and global competitiveness in the smart-sensor field.
Freesor’s core offering spans open-loop and closed-loop Hall-effect current sensors, Hall-effect voltage sensors, and DC leakage current sensors, all developed under its proprietary FREESOR brand. These sensors are widely applied in new energy vehicles, photovoltaic systems, energy storage, rail transit, data centres, industrial automation and white-goods domains where high precision, stability and anti-interference performance are critical.
Leveraging advanced automated production lines and a global footprint of customers across more than 60 countries, Freesor is committed to optimizing capacity and shortening delivery lead-times. The company emphasises service upgrade and technical support, pledging that every client requirement will receive timely response through a professional team. Its strategic goal is to become the overall-application‐solutions provider of electronic products for the sensor sector.
Driven by innovation, Freesor holds multiple proprietary technologies and has established itself as a trusted partner in the sensor ecosystem. With the backing of Keli Group, Freesor is poised to lead the global sensor industry and bring greater value to customers and society alike. Its vision is clear: “through continuous technological innovation and service optimisation, Freesor will become a leader in the global sensor field.”
