To replace the aging AEM-7 and unreliable HHP-8, Amtrak ordered a variant of the Vectron from Siemens. It is used as ACS-64, which means “Amtrak Cities Sprinter 6,400 hp”. It only delivers 5,000 kW permanently and 6,400 kW for short periods and is designed for the three different AC systems on the east coast. The locomotive body was designed to be significantly more stable and heavier in accordance with American crash standards. Amtrak procured 70 and SEPTA, which operates transit services in the Philadelphia area, received 15. 