The ABB 9T51B0109 Buck-Boost Transformer is a versatile and efficient solution for adjusting supply voltage levels. With a capacity of 0.75Kva, this transformer features dual voltage primary and secondary capabilities, allowing for a wide range of voltage combinations. It is designed to either buck (lower) or boost (raise) the supply voltage by a small percentage, typically between 5% and 27%. Housed in a NEMA 3R nonventilated weatherproof enclosure, it is suitable for both indoor and outdoor applications. The transformer is equipped with an encapsulated copper core and coils, along with an integrated junction box that includes a ground lug for straightforward wiring. This makes it particularly useful when wiring three units together to form a 3-phase autotransformer. The improved termination spacing and ample wiring compartment provide flexibility in selecting various UL listed connectors for either copper or aluminum cables. The ABB 9T51B0109 is RoHS compliant, UL and cUL Listed, and meets the seismic requirements of IEEE-693-2005, IBC-2021, and CBC 2022, ensuring reliability and safety in diverse environments.