• PCC Controller

  • General discussion about fallen trolley and interurban lines in North America, past and present.
General discussion about fallen trolley and interurban lines in North America, past and present.

Moderator: Aa3rt

  by farecard
The PCC's allegedly had a XD-323 traction controller controller. I'm seeking further descriptions &/or pictures of such.

Any suggestions?
  by polybalt
There were two manufacturers of traction equipment for PCC cars, Westinghouse and GE. I understand they were quite different. The number you gave is a Westinghouse controller used on early PCC's as far as I know. There were many changes, and changed numbers, over the years. There is a a bench display of PCC-style control in Kenosha, shown at the link below. Not shown is the master controller, which was foot-pedal operated, much like an automobile. Chicago streetcars were the exception, with an odd handlebar-like system allowing operation with hands, not feet.

The drum style controller used on PCC's were typical, but I think the last order of car in Boston used a conventional cam controller with sepaarate resistance grids? And Chicago had hundreds of rapid transit cars with PCC control.

  by farecard

My attempt to find pictures of cam controllers has also been frustrating; you'd a thunk such an widely deployed technology would have many cites, but not that I've found.
  by Gerry6309
The XD323 controller is one of a group of similar devices used on PCC cars and nicknamed "Washtubs" due to their shape. The XD323 was an early version used on air-electric cars. Every version of the Washtub was similar, with a pair of horseshoe shaped copper rings mounted on the inside edge of an insulating ring. Mounted to the inside of the ring are 99 moveable contacts, which are pressed against the ring by a pair of rollers, mounted on a rotation carrier. One mounting bolt for each finger extends outward from the ring, providing a point to which resistance ribbons are clamped. These are set up to create two rheostats, which operate in tandem. The rheostats are wired to give 75 steps of acceleration and 99 steps of dynamic braking. The carrier is driven by a pilot motor, and includes a drum with interlocks to operate field shunts and stop the motor at the end of its travel. Later versions include the XD373, XD423, and XD473.