The oil-immersed transformer features its core and windings fully submerged in insulating oil, typically mineral oil or eco-friendly natural ester, providing excellent heat dissipation and strong overload capacity. It operates stably under natural oil circulation or forced air cooling while withstanding short-term surges. Standard accessories include a fully sealed tank, oil level gauge, temperature controller, and Buchholz relay for long-term reliability. These transformers are widely used in power substations, industrial distribution, outdoor compact substations, wind power step-up stations, and PV plants. Compared to dry-type transformers, they offer more mature large-capacity manufacturing and lower unit cost, making them ideal for continuous operation. When natural ester oil is selected, the flash point exceeds 300°C, significantly improving fire safety while being biodegradable. Overall, oil-immersed transformers strike a good balance among reliability, economy, and heat dissipation, serving as a proven choice for outdoor or high-temperature long-term projects. We offer customized configurations in capacity, voltage class, and cooling method.