Conduit for streetcar operation

1775 views
25 replies
1 rating 2 rating 3 rating 4 rating 5 rating
  • Member since
    June 2002
  • 16,114 posts
Conduit for streetcar operation
Posted by daveklepper on Tuesday, October 24, 2017 11:18 AM

Did not know I had done such a thorough job of photographing features of the Washington, DC, plowpit I visited in Autumn, 1947, age 15+, courtesy Richard (?) Ellis, a Capitol Transit supervisor and a fellow ERA member.  (He was also a practicing Methodist Minister who gave a good invocation-welcome at the start of every ERA Convention banquet.)  The photos due explain a lot about how the counduit worked.  He later move to employmenet as a full-time cleric in Pittston, PA, midway between Scranton and Willksbarre, so we met-up again railfanning on my Wednesday days off as a 18-year-old summer-camp photography counselor at Camp With-a-wind, Honesdale, PA, in 1950.

Look forward to your additions.

Tags: Conduit
  • Member since
    September 2010
  • From: Parma Heights Ohio
  • 3,390 posts
Posted by Penny Trains on Thursday, October 26, 2017 7:41 PM

Ok.  I've been looking at these for 2 days and I still don't know.  What is it?

Big Smile  I'm Cuckoo For Choo Choo Stuffs!  Big Smile

  • Member since
    August 2010
  • From: Henrico, VA
  • 8,955 posts
Posted by Firelock76 on Thursday, October 26, 2017 7:53 PM

Becky, that's the below-street-level electrical conduit system that Washington DC's trolleys ran on.  Overhead wires were prohibited in the District so the trolley's got their juice from channels in the street. 

At least I'm sure those are the pictures David's posted.  I'm sure he'll correct me if I'm wrong.

And oh yeah, corrosion was a problem.

And David, if you're looking in...

Good Lord sir, aside from the moon is there anywhere you haven't been?  You continue to amaze me!

  • Member since
    April 2015
  • 319 posts
Posted by Enzoamps on Thursday, October 26, 2017 11:08 PM

Look in the center of the track, there is a metal slot centered between the rails.  You can see it where the men are working.  A shoe from the car truck went down through that slot as the car rode along.  COntacts on eitherside of that show rubbed agains the metal strips in the little tunnel.  In one of the photos you are looking sorta back down the beginning of that tunnel,  the two contact strips are seen emerging from the tunnel and spreading a little.  the shoe went in between them.

The pickup shoe was of course wider than the slot, so there was a small covered pit in the center where the changeover occured.  They dropped the shoe into the pit, then returned the cover and rode off.

  • Member since
    June 2002
  • 16,114 posts
Posted by daveklepper on Friday, October 27, 2017 12:55 AM

The explanaition was correct except for changeover.  The double-contact shoe (one side positive and one negative, polariity not imiportant and not consistent) was slid off horizontally by the man in the plowpit and then put on a shelf to be inserted in the carrier under the truck bolster of an inbound car, the pit spanning the width of two tracks.  The photo showing the front of the PCC above the end of the slot at the pit is for the outbound track, the inbound shows the the beginning of the conduit for the inbound track, since it is possible that the carrier was not accurately centered when the plowman inserted the plow into the carrier.

I believe that Third Avenue's practice was only slightly different, in that both tracks were treated like iinbound tracks regarding the end of conduit, in case there would be a need for single=track operation.  Not certain about this.  Am certain the a somewhat wider side-to-side movement of the plow was possible.

The street scene shows maintenance people removing an oject that someone had dropped into the slot.   It is not at a changeover point.

Two men regularly manned plowpits on busy lines, one in the pit and one on the street to handle the trolley poles. On lighter lines, the operator did the pole movement.   But then starting in 1948 or 1949, Capitol Transit started motorizing trolley poles so they could be railsed and lowered by the operator at the controls, on PCC cars and the 20 pre-PCCs, if my memory is correcgt.

  • Member since
    May 2020
  • 2 posts
Posted by Dot-connector on Monday, May 4, 2020 2:59 PM

Hello David,

I am working on an exhibit for the National Capital Trolley Museum and was wondering if you have any photos of the carrier the conduit plow rode on. These here are amazing, and I would like to draw an image showing just how the conduit plow rode on the carrier. I am only using images for reference, and would not reproduce them.

Thank you so much for your helpful information so far. You are amazing!

  • Member since
    June 2002
  • 16,114 posts
Posted by daveklepper on Monday, May 4, 2020 6:12 PM

These are all the pjotos related to the subject that have scanned and fixed so far.

The plow did not ride on the conduit, but was suspended from a carrier attacvhedtp the  truck bolster (In DC and NYC, London carrier attached to car body), and was guided by the sirface conduit rales and depressed positive and negative current rails.  Carriers allowed side-to-side movement.

 

 

 

  • Member since
    May 2012
  • 4,060 posts
Posted by rcdrye on Monday, May 4, 2020 6:58 PM

Assuming Maine ever reopens I'll try to get under DC T 1304 this summer to get a photo.  The plow hanger is still there even after the car went to GE for propulsion equipment experiments.  The shop guys at Seashore have a pretty good idea how to fix a troublesome electrical problem, so it's hoped 1304 will be "live" by the end of the year.

Some of DC Transit's slot-equipped trackage was originally set up for cable traction, but all of it was eventually rebuilt with a deeper slot.  New York's Broadway and Third Avenue lines were converted from cable to electric under traffic - at least the slot rails were installed that way.

Some or all WB&A interurbans had the plow hangers mounted to the car body.  It was preferred to operate with the plow on the rear, to make coasting through switches and crossings easier.

  • Member since
    June 2002
  • 16,114 posts
Posted by daveklepper on Tuesday, May 5, 2020 3:16 AM

All my pit pictures were taken at the Georgetown Pit on the Cabin John ("20") line.

Third Avenue had only one operating pit after the 125th Street - Willis Avenue (Bronx) line was convereted to buses before WWII to permit consdtruction of the Tri-Boro Bridge.  That closed pit was at 1st AVenue and 126th Street.  The remaining Third Avenue pit, in use until August 1947, was at 145th Street and Lenox Avenue, used by the 149th Street Crosstown X  and until June 29 1947 by the Broadway-145th Street every-45-miniutes one-car franchise line, that changed from conduit to trolley-pole just to reach its trailing crossver to reverse.

The last Manhattan all-conduit lines, the "K" Kingsbridge-Broadway-125th Street line, with put-in pull-out moves down 3rd Avenue to the 65th Street main carhouse and shop, quite 29 June 1947.   The Bronx saw streetcars until the 1952 closure of the Yonkers lines that entered The Bronx to reach the subways (on existing elevated structures) at Woodlawn (Yonkers "4"), and B'way-242-Van Courtdland Park (Yonkers 1, 2, 3).  PCCs  in Broolyn till 1954, QBridge 1957.

Shore Line Trolley at East Haven has a conduit plow on display in a display case.

I think the plow carrier was remvoed from operating 629, originally a conduit-only 1939-home-built 59th Street Crosstown car, used Sundays on 42nd Street and November 1946-March 1947 on Thrid and Amsterdam Avenue, either by Third Avenue or when it was operated in Vienna 1948-1967.

  • Member since
    May 2012
  • 4,060 posts
Posted by rcdrye on Tuesday, May 5, 2020 6:28 AM

daveklepper
I think the plow carrier was remvoed from operating 629

I'm pretty sure sister 631 is also missing a plow hanger.

  • Member since
    June 2002
  • 16,114 posts
Posted by daveklepper on Tuesday, May 5, 2020 2:08 PM

 

and 631 was also originally a 59th street car.   626-645

646 - 685 poles fot The Bronx

  • Member since
    May 2020
  • 2 posts
Posted by Dot-connector on Wednesday, May 6, 2020 4:15 PM

Thank you for the offer! Actually, I imagine Maryland will open about when Maine does, and I will again have access to #1101, which also still has its plow bracket. I have a picture of a plow installed under a similar PCC car, but can't quite make out what is bracket and what is truck. I have another image of a conduit plow in the museum's collection, which I added to this image for comparison. I wanted to show the folks here so I could ask intelligent questions. If I ever figure out how to submit pictures to this blog, I can post it. Apparently, a link to GoogleDrive does not work. I may have better luck with a Flickr link.

  • Member since
    May 2012
  • 4,060 posts
Posted by rcdrye on Monday, May 11, 2020 6:24 AM

The hatches in the street allow access to the slot contactor supports.  The spacing - roughly 15 feet apart on straight track - is a remnant of Cable conduit construction.

  • Member since
    May 2012
  • 4,060 posts
Posted by rcdrye on Monday, May 11, 2020 6:41 PM

Both positive and negative conductors were in the slot - polarity does not matter with series wound motors. 

  • Member since
    September 2011
  • 4,687 posts
Posted by MidlandMike on Monday, May 11, 2020 8:52 PM

Why didn't they use a single conductor/wire like the trolleys?

  • Member since
    May 2012
  • 4,060 posts
Posted by rcdrye on Tuesday, May 12, 2020 6:58 AM

MidlandMike

Why didn't they use a single conductor/wire like the trolleys?

 

The "Electric Railway Handbook" doesn't say.  My working guess is that there was local opposition in both Washington and New York to using the rails as the negative return to avoid electrolytic action on pipes and and such - no small consideration when gas pipe is run in the same street.  Having a power rail on each side also kept the Plow centered. K controllers had variants used for non-rail return - also used in Cincinnati.  Where cars moved between conduit and non-conduit track the G lead was connected or disconnected from the frame as needed.

  • Member since
    May 2012
  • 4,060 posts
Posted by rcdrye on Tuesday, May 12, 2020 5:28 PM

According to Richey and Greenough's monumental "Electric Railway Handbook" (McGraw-Hill 1915):

"The distribution system is identical for positive and negative sides and is controlled at substations by double-pole double-throw switches, which make it possible to reverse the polarity if necessary on account of gounds on different sides of different circuits."

  • Member since
    September 2011
  • 4,687 posts
Posted by MidlandMike on Tuesday, May 12, 2020 8:25 PM

Did conduit systems use reversing loops at the end of the line.  It seems they would have the same problem as a 2 rail model RR.

  • Member since
    May 2012
  • 4,060 posts
Posted by rcdrye on Wednesday, May 13, 2020 6:13 AM

MidlandMike

Did conduit systems use reversing loops at the end of the line.  It seems they would have the same problem as a 2 rail model RR.

 

Just leave a gap to coast through.  Since polarity doesn't matter it's not a problem.  Same using a crossover for double ended cars.

  • Member since
    June 2002
  • 16,114 posts
Posted by daveklepper on Wednesday, May 13, 2020 9:23 AM

The Third Avenue System, Manhattan, The Bronx, and Westchester County, had only two loops, at 129th Street and 3rd Avenue for pole cars from The Bronx, track in through summwe 1947, but service stopped around 1938 because of one-way traffic on 3rd Avenue bridge (The elevated's was at 2nd Avenue.) and Classon Point on Long Island Sound in the very-far-east mid-Bronx, whch was bussed in the 1st post-WWII Bronx conversion in March 1947.  All Third Avenue and New York Railways equipment was double-end, and single-and double-track terminals were used throughout the system.

The ends of all Washington, DC, lines excep the single-track, single-car Belltsville-Branchville shuttle, had loops, and all its PCCs were single-end, as were some of its older deck-roof cars.  Some short-turn (cut-back) points, including a few in conduit territory, has simple trailing crossovers, and this required the retention of some double-end cars.  Brooklyn was a mixture, but all its 100 PCCs were single end, and no conduit was used in Brooklyn after Third Avenue withdrew its Manhattan Bridge service around the time of WWI.

You can send me conduit-related photos, davekleppper@yahoo.com, and I'll gladly post them.

  • Member since
    January 2019
  • From: Henrico, VA
  • 4,181 posts
Posted by Flintlock76 on Wednesday, May 13, 2020 10:26 AM

MidlandMike

Why didn't they use a single conductor/wire like the trolleys?

 

I could be wrong on this, but they didn't want overhead trolley wires in Washington DC due to the "eyesore" factor.  

Anyone feel free to correct me if I'm wrong.

  • Member since
    June 2002
  • 16,114 posts
Posted by daveklepper on Wednesday, May 13, 2020 4:07 PM

Correct

  • Member since
    January 2019
  • From: Henrico, VA
  • 4,181 posts
Posted by Flintlock76 on Wednesday, May 13, 2020 6:46 PM

Whew!  

Thanks David!

  • Member since
    June 2002
  • 16,114 posts
Posted by daveklepper on Friday, May 15, 2020 4:43 AM

answering a questiono to my email box.   N-S street is Broadway

"C" to B'way & 263nd St.,  NY-Yonkers Line

"K" to 125th ST. and 3rd Ave., plus Bronx pull-ins and put-outs, Kingsbridge Carhouse at B'way 215th St., south end of this overhead wire.

Tracks on W. 225 used by "C" and Bronx pull-ins and put-outs

 

  • Member since
    June 2002
  • 16,114 posts
Posted by daveklepper on Saturday, May 16, 2020 5:33 PM

I lived in Manhattan, but Jack May lived in The Bronx.  So, his memry of Marble Hill is better than miine, as proven by my own photos.  So a major correctioin has been made:

  • Member since
    June 2002
  • 16,114 posts
Posted by daveklepper on Wednesday, May 27, 2020 4:03 PM

Posting  Dot-Connector's provided photo of the installation of the plow carrier under a PCC car's truck in the Georgetown Carhouse.  The orange stripes are the rails supporting the plow that allow it to move side-to-side.

SUBSCRIBER & MEMBER LOGIN

Login, or register today to interact in our online community, comment on articles, receive our newsletter, manage your account online and more!

FREE NEWSLETTER SIGNUP

Get the Classic Trains twice-monthly newsletter