This manual contains important instructions that you should follow during installation and maintenance of the Battery Energy Storage System and batteries. Specifications are subject to change. To. . As the integration of battery energy storage systems (BESS) with any new PV project is quickly becoming the norm rather than the exception, it is important to know why and when to incorporate an isolation transformer in your next PV + BESS project. The installed capacity is. . The step-up transformer skid station converts low-voltage AC power generated by the power conversion system (PCS) into medium-voltage AC power and feeds the power into the power grid. The guide is divided into three main. .