The 3:3 transformer‑less UPS combines compact design with advanced functionality, delivering an output power factor of up to 1 and on‑line efficiency of 95.6% for reliable performance with minimal energy loss. Capable of handling inductive and capacitive loads without derating, it supports parallel operation of up to six units for scalability. Its modular design allows easy front‑side maintenance, while fan redundancy and speed control enhance reliability. With on‑line double conversion and high‑frequency technology, it covers capacities from 10 to 1000 KVA. User‑friendly features include one‑click upgrades via upper computer software and comprehensive circuit breaker configurations for seamless control of mains, bypass, maintenance, and output, making it an efficient and flexible solution for critical environments.