Number 90 posted:
* With the Alco-GE PA series, the two mechanical shutdowns would stop the train's progress, but the ground fault might not do so. The high voltage ground would be worked around by resetting the ground relay and using the traction motor cutout switch -- something the EMD unit did not have (or need) -- to cut out either the No.1 or No.2 truck, whichever had the grounded traction motor, by trial and error. If each truck had been independently cut out and the ground condition was not found by doing so, then the ground would be elsewhere in the system and any of the three en route failures would leave the PA and its train stopped, awaiting rescue.
Are you suggesting that the E unit engineer did NOT have the ability to reset or isolate traction motors or trucks? This does not seem right to me, could you expound further?
