Just Testing, No Stopping. Southeastern Pennsylvania Transportation Authority (SEPTA) Test Extra 901/2408 is passing through the low level platform at Bristol, Pennsylvania (at a very high rate of speed) on the morning of Saturday, February 24, 2018. Not even 30 minutes before we were bathed in sunshine but the weather took a dramatic turn for the worse. This was SEPTA’s first tour of the system for its first Siemens ACS-64, putting its existing electric engine fleet on definitive notice of a short remaining life.