Here are a few photos of the visiting historic equipment at the recent East End Shops open house

http://www.railpictures.net/viewphoto.p ... 51&nseq=25

http://www.railpictures.net/viewphoto.p ... 55&nseq=24

http://www.railpictures.net/viewphoto.p ... 47&nseq=26

http://www.railpictures.net/viewphoto.p ... 55&nseq=32

here's 522 pulling a "photo freight" at the 9th St industrial park for a visiting railfan group

http://www.railpictures.net/viewphoto.p ... 94&nseq=50

NS was very supportive of the Roanoke Chapter NRHS mechanical folks during this event. Chapter mechanical personel received assistance with getting 522 FRA certified, and were allowed to use shop facilities for several jobs . For the return trip to Chapter trackage at 9th St, the locos were run back across town under their own power by an NRHS crew with an NS pilot. The guys couldn't have asked for better treatment from NS, and the relationship between NS and the local rail preservation community seems to be greatly improved over past years. Thanks again NS for a great show.

Gee, with that lovely articulated back at the shops, it seems like an awful waste not to simply complete restoration before putting her back in temporary storage!

Nice images of the preserved fleet. Thanks for posting them.

What's the difference between an Alco S1 (or 2) and a T6?

The T6 or transfer switcher could change the traction motors from parallel to series circuit for higher speeds.

The T-6 was also a later production model than the S-1's and used the 251 power plant. The hood was a shorter version of that used on the RS-11's, with notched out number boards. The N&W T-6's were delivered in 1959 and retired the last of the S1 0-8-0's in yard service. 41 is a sweet running locomotive. It is very responsive and will pull just about anything you put behind it. We originally restored it in 1990-91. It has been a "guest locomotive" at Spencer and was in revenue service on the West Virginia Central for several years.

There were still a few T-6's in service during my brief stint with the N&W in the early 80's.

They were generally known as "tea kettles" due to their distinctive sound when idling. Sort of a "blub-blub-blub-blub".

Nifty little engines (for diesels). ;-)

Isn't that backwards? Series would net the motors 300 volts, and parallel 600 volts, thus running at a higher speed.

Bob Kutella

I'm not an electrical engineer, nor have I operated a diesel-electric, but I don't think its so simple. By increasing the exciting voltage, you can still get 600 volts despite having doubled the resistance. And we also have to consider the amperage which is part of the wattage calculation for total power. But I will defer to someone who actually knows how it works. <G>

But going back to the orginial question, it was the ability to switch distribution (transition control) that made the T6 different from the S6 mechanically. Both were equiped with the 251B engine although the T6 was rated with 100 more horse power - 1000 verses the S6's 900 HP.

The traction motors would have been connected in series for starting and low speed. The normal transition sequence on a 50's era diesel would have been series, series-shunt, parallel, parallel-shunt. Diesels worked more or less like this until the SD-50's came along and dispensed with transition (for a while at least) until transition stages were later added to the main alternator to improve efficiency (according to what I was told).

I'd guess that modern AC traction has dispensed with transition altogether (?).