• Power bus bar connector on roof of RDG MU's

  • Discussion Related to the Reading Company 1833-1976 and it's predecessors Philadelphia and Reading Rail Road and then the Philadelphia and Reading Railway.
Discussion Related to the Reading Company 1833-1976 and it's predecessors Philadelphia and Reading Rail Road and then the Philadelphia and Reading Railway.

Moderator: Franklin Gowen

  by chnhrr
I took a trip today to the Railroad Museum of Pennsylvania. One of the displays includes a Reading MU commuter coach. What was the purpose of this device mounted at the front of the roof? It appears that this was unique to Reading Company.
  by glennk419
The device at the roof ends of the original Reading MU's was a power bus bar contactor. The MU cars had bus bars which ran the length of the cars and were connected to the pantographs and the system allowed multiple cars to draw overhead power through a minimum number of raised pantographs. This was designed to save wear on both the pantographs and the catenary. The bus bar system was removed from the cars prior to the opening of the Center City Commuter Tunnel due to clearance issues and the presence of the phase break between Amtrak / Septa power at Girard Avenue.

The cars can be seen with the bus bars / contactors removed here: http://www.thebluecomet.com/rdgWTrent1.jpg
Last edited by glennk419 on Tue Oct 12, 2010 8:01 am, edited 2 times in total.
  by ex Budd man
The bus bars were gone by the time I hired in 1985 but the magnet valves which operated them could still be found on some cars. The car in the photo was equipped with air conditioning as IDed by the grill above the lead truck on the non-pantograph end. The M-G set was replaced with a M-A set which produced the 230 v 3 ph. AC needed for the A/C units. BTW the A/Cs were the same as the units in the SLII and III cars.
  by JimBoylan
The Great Northern Electric locos that the Pennsylvania bought about 1957 and numbered 1 through 7 had almost that same system, but PRR removed them.
  by chnhrr
Thanks all for the information! Jim - after I posted the topic, I thought I had seen a similar device on a locomotive. It dawned on me it was one of the western electrics which was one of the Great Northern boxcabs.

Other roads such as the New Haven, Pennsylvania, South Shore, Illinois Central and Lackawanna etc. who had electrified divisions did not find this devise advantageous. I wonder who manufactured these devices, was it G.E.?
(Photo courtesy D. Ross)
  by chnhrr
I meant to ask this question earlier, call it a delayed reaction. Unlik the New Haven and PRR the Reading MU cars were for the most part all motorized. How was it determined which car would have the pantographs up or down on a run? Or was it that certain cars had the pantograph and it this were the case how many cars would have pantographs per train length?
  by JimBoylan
A Reading Co. electrical instruction book mentioned how many pantographs to be raised per cars in a train. At one time, it was to be just the 1st and last pans, although later the crews would use a few more. A knife switch in a switch cabinet in each power car could cut out the electricity that would open the latch that kept the pantograph down. Since trailer 799 had a pantograph, it also had that switch. I can remember seeing trains freshly coupled together at Reading Terminal, after all the switches were set as desired, lower all raised pans, and then raise only the intended ones.