ABB ACS580-01-077A-4+B056Product Description Drive, AC, 50HP, 480V, 65. 0A, CT, N12 ABB's ACS580 01 077A 4+B056 series drive is a highly efficient energy converter. It's designed with a number of features to maximize reliability and minimize downtime, including a built in, dynamic brake chopper and programmable feedback source. This drive helps to deliver cost savings and an improved user experience through reduced maintenance costs and superior motor control.