The ABB 9T51B0102 Buck-Boost Transformer is a versatile and efficient solution for adjusting supply voltage levels. With a power rating of 0.05Kva, this transformer features a dual voltage primary and secondary, 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 wiring compartment provide flexibility in selecting various UL listed connectors for copper or aluminum cables. Compliant with NEC Article 210-9, Exception 1, when field connected as an autotransformer, the ABB 9T51B0102 is also RoHS compliant, UL and cUL Listed, and meets the seismic requirements of IEEE-693-2005, IBC-2021, and CBC 2022.