ABB 609903-T001 SS4 Solid State Trip Unit

ABB 609903-T001 SS4 Solid State Trip Unit is a Type SS4 solid-state protection module in ABB’s Power Shield family, engineered to deliver precise, fast-acting protection for compatible ABB breakers used in industrial power-distribution systems. Identified by the part number 609903-T001, this unit is listed in multiple sources as a Power Shield SS4 solid-state trip unit designed for high-current protection schemes. The SS4 family employs solid-state sensing and logic to determine a trip condition, offering digitized protection within ABB’s protection architectures, and is commonly configured in three-pole SS4 installations for ABB equipment. In practical use, this trip unit supports protection of feeders, motors, and transformers in industrial facilities that rely on ABB protection products. Related trip-unit entries in the SS4 line, such as 609901-T501, illustrate the range of compatible modules within ABB’s SS4 lineup.