Siding thrown over to locate main track signal between main and siding

C & 0 Has Good Ideas in CTC

Sheet-metal houses not only at switches but also at interme­ diate signals and use of hold-out signals are features of this project. Well organized construction requires no work trains.

TO INCREASE TRACK CAPAC­ portant freight line. Numerous Windsor, Ont., and Blenheim, Ont. ITY, facilitate train movements industries , including large, automo­ Previously no signaling was in and reduce operating expenses, the bile factories, are located at Plym­ service on the single track between Chesapeake & Ohio has installed outh , Flint and Saginaw. Also the Plymouth and Kearsley interlock­ centralized traffic control on 55 Plymouth-Saginaw section is part ing at Flint. Two tracks extend miles of single-track between Plym­ of an important route to and from north from Plymouth 1.0 mile to a outh, Mich., and Mount Morris, Ludington, Mich., which is the port power switch which is included in Mich. This project connects with for C&O car ferries, operated all the new CTC. At Wixom there are CTC previously in service on 24 year, across Lake Michigan to and two sidings with power switches miles between Mt. Morris and from Wisconsin ports of Milwau­ included in the CTC. Other sidings Saginaw, Mich., the entire 79 miles kee, Manitowoc and Kewaunee. with power switches included in between Plymouth and Saginaw the CTC are at Clyde and Newark. now being controlled from a ma­ Twenty Trains Dally These sidings were lengthened to chine at Saginaw. hold 112 and 133 cars respectively . This project is complete CTC Fourteen freight trains are sched­ The turnouts at the ends of these with power switches and full com­ uled daily, with extras as required, sidings are No. 16 with 32-ft points, plement of three-aspect signals for totaling 14 to 20 trains daily. Eight so that trains can enter or depart directing train movements from of the scheduled trains are on this at speeds up to 30 mph . Each sid­ siding to siding, with intermediate Plymouth-Saginaw section at night ing is equipped with a track circuit, signals generally spaced about 2 between 9:30 pm and 7:00 am. In which not only controls a track­ miles to 3 miles apart for following addition to the Plymouth-Mt. Mor­ occupancy lamp on the track dia­ trains in each siding-to-siding ris CTC discussed here, CTC is gram of the control machine , but block. Thus every provision is also being installed for operating also enters into the control of the made for maximum utilization of trains in both directions, on 17 signals governing train movements track, and for minimum spacing miles of two main tracks between into the sidings. between following trains . Plymouth and Detroit. Also, CTC With a siding unoccupied, if the No passenger trains are operated is under construction on 68 miles dispatcher reverses a switch and on this section, but it is an im- of single track of the C&O between sends a control , the entering signal

RAIL WAY SIGNALING and COMMUNICATIONS FEBRUARY1958

Digitized by Google - - - - . - ---- Abov_..ew small-111:ecl backgrounds 15 In. In diameter are new standard on part of this prolect and the next

Right-In house at an Intermediate slgnal the plug-In type relays are on a hinged bracket that swings out

will display red-over-yellow-over­ ing is protected by a manually­ patcher positions his levers and red, and the approach signal will controlled interlocking . Plans are sends out controls to hold the four display yellow-over-green, so that being considered to control this in­ hold-out signals at Stop. This es­ the engineman has proper informa­ terlocking from the GTW machine, tablishes protection for the switch­ tion to bring his train up to and somewhat the same as the one at ing in the area between the two through the turnout at the speed Wixom. pairs of signals, and allows the for which it was designed. This dispatcher to clear a signal for a saves precious time when making Hold-Out Signals Save Time through train to proceed from the meets, compared with conventional next siding toward Grand Blanc. practice which includes no track At Grand Blanc, seven miles If, before the allotted time has ex­ circuit on the siding and only a south of Flint, the C&O serves a pired, the switch engine clears single yellow on the approach large automobile factory, the con­ the main track, this is shown by signal. If a siding is occupied, the nection to the main track including the corresponding track-occupancy entering signal cannot be cleared four single switches and two cross­ lamp on the dispatcher's machine. for a second train to enter. overs, in a distance of about one He can then clear the holding sig­ Previously a manually-controlled mile. In order to permit switch en­ nal for the through train to proceed electric interlocking was in service gines to work back and forth be­ on through Grand Blanc without at Wixom, where the C&O crosses tween the main track and the in­ stop or delay. All main track hand­ a secondary line of the GTW. dustry tracks, for maximum time throw switches in this territory are When installing the CTC, the con­ without delaying through trains, equipped with electric locks, con­ trol of this interlocking was in­ lever-controlled hold-out signals trolled as part of the CTC. cluded in the CTC machine. were located at both ends of the The switch machines are the At Holly, the C&O crosses the Grand Blanc area . type 5D with dual control. The single-track line of the GTW be­ When switching is to be done for biased type controllers are in the tween Detroit and Durand, which an authorized time on the main switch machine housings. The is equipped with CTC. This cross- track at Grand Blanc, the dis- switch motors are rated at 24 volts

FEBRUARY1958 RAILWAY SIGNALING and COMMUNICATIONS 35

Digitized by Google power siding to the other end. This cable is supported by a Copper­ weld stranded messenger using a spiral winding made of copper rib­ bon ¼4-in. thick and o/i6 -in. wide Commercial a.c. power being available at every power siding and some intermediate signals, made it possible to eliminate several miles of line wire on the pole line for a.c. power transmission. No Work Trains Materials were assembled at con­ struction headquarters near Plym­ outh. Highway trucks were used to haul these materials to field lo­ cations. Highways and secondary roads were available so that trucks could be driven to nearly all the power switch locations and to many of the intermediate signals. For inaccessible locations, materials were hauled on track motor cars and trailer from the nearest road A lheet-metal h-M, ln,tead of caM,, I• uMd at lntenllfflate 1l9nal, crossing. Thus, no work train serv­ so that relay, and battery are not expoMd to rain during ln,pectlon, ice was required. The use of sectional type sheet­ d.c., supplied by 12 cells of 80-a.h. is attached to anchor bolts in the metal houses, and sectional con­ lead storage battery, which also concrete. The roof, also, is made of crete foundations, assembled at operates the local CTC code equip­ sheet-metal section 16 in. wide. The final locations, was an important ment. At each intermediate signal door is sheet-metal. After such a factor contributing to the success there is a set of 6 cells of 60-a.h. house is erected, plywood is ap­ of eliminating work train service, lead battery that feeds the local line plied inside on the walls and ceil­ which would have been very ex­ circuit and the searchlight signal ings. This is ¼-in. plywood, except pensive on this territory because of operating coil. At places where a.c. on one wall which is l-in. for interruptions of work to let trains power is available to operate recti­ mounting the terminals, arresters, pass. Power equipment such as the fiers, each track circuit is fed by one rectifiers and transformers. The re­ Jeep-A-Trench were used to dig 80-a.h. storage cell. The storage lays are the plug-in type mounted ditches for buried cable, and to aid battery on this project was fur­ in a rack on a framework made of in erecting signal masts. nished by Exide. Fansteel and 1-in. angle iron. This frame has a G.R.S. rectifiers are used to charge hinge to swing out, thus giving New Smaller Shields the batteries. Where no a.c. is avail­ access to the rear. The storage bat­ able, each track circuit is fed by teries are in wood trays on the floor. The signals on this project are two cells of 1,000-a.h. Edison pri­ The signal foundations are the sec­ the searchlight type. On nearly all mary battery in multiple. tional pre-cast concrete type. of this territory these signals have The signal lamps are single­ the conventional circular back­ Sheet-Metal Houses at filament rated at 12-16 volts, 21 ground. However, on a few of the All Locations candlepower, and are burned con­ signals, the new 15-in. circular tinuously as an additional aid to backgrounds are used, and these Sheet-metal houses for relays and men working along the tracks to smaller backgrounds are being battery were installed, not only at warn them of the approach of used on other CTC projects under the ends of sidings, but also at the trains. construction between Plymouth intermediate signals. The reason and Detroit. for using houses, rather than cases, C&O Owns Pole Une This project was planned and is that the equipment is not ex­ constn1cted by signal forces of the posed to rain or snow when equip­ The pole line, which is used for C&O Northern Region under the ment therein is being inspected, communication wires and signal direction of R. W. Margsh, Assist­ and the houses give protection to wires, is owned and maintained by ant Signal Engineer, and A. J. maintainers performing their work the C&O. Only four signal wires Detzler, Supervisor Signal Con­ in stormy weather. extend the length of the project. struction, with headquarters at De­ The houses at the ends of power Two No. 8 copper wires are for the troit, and under the jurisdiction of sidings are 8 ft by 8 ft, and at in­ CTC code line, and two No. 10 T. L. Carlson, Superintendent of termediate si~als 5 ft by 5 ft. Each Copperweld are for the local signal Signals, and M. F. Anderson, Gen­ house is made of portable sections line control circuit, which is for eral Superintendent Signals and 16 in. wide, set vertical to form either northward or southward sig­ Communications, at Richmond, Va. walls. When assembling such a nals in a siding-to-siding block, de­ The major items of signal equip­ house, a concrete slab 6 in. thick pending on direction of traffic set ment were furnished by General is poured in place on a leveled up by CTC control. Railway Signal Company. ground surface. A channel iron, Twelve-conductor No. 14 aerial which forms a base for each wall, cable is used from one end of each

36 RAILWAY SIGNALING and COMMUNICATIONS FEBRUARY1958

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