Wires And Controls

Wiring your first train set is so simple, of course, that it is really not wiring at all—just hooking a couple of things together. Even when you add switches and a dozen other accessories and have a maze of wires that looks quite for- bidding, wiring is still not a difficult task to understand or perform, especially if you attach one new thing at a time and test it before going on to another. All you need to do is follow the manufacturer's instructions and remember that electric current flows out from the transformer along one wire and back again along another—and never the twain shall meet except at the terminals of an object it is supposed to work. And even then they don't meet where you can see, for the terminals are always separated and insulated from each other. In thinking of this flow of elec- tricity, consider the two rails of your track as just extensions of the wires, with the pickup wheels of locomotive or tender as the terminals of the object to be worked by the electric current.

The control lever on the transformer is like a faucet that shuts off the flow of current when closed, allows the current to flow when it is opened, and allows more and more to flow the farther you turn it. A poor wire connection or loose joining of rails is like a leaky or clogged pipe. A com- plete break or gap in the circuit anywhere, in either wire ' rail, stops all flow of current everywhere, because cur- rent must move through the entire route from trans- former to working object and back to transformer again; otherwise it will not go anywhere.

Some gaps in the circuit are intentional, some are accidental. A switch, for example, is a gap in the circuit that is meant to be there. When the switch is open the current will not flow. When the switch is closed, the gap is closed and current flows. When you push a button on some of your accessory controls, you just close a gap and allow current to go to the accessory and back to the transformer.

Accidental gaps occur when a wire comes loose or when a rail connection comes open. When a light bulb burns out, the current stops flowing only if the lights are wired in series, which means that the main line runs through the bulb. Most Christmas tree lights are wired this way, but usually the lights on your train set are not. They are wired with branch lines; even if the burned-out bulb stops the flow of current in the branch line, nothing happens in the main line because there is no gap there. It by-passes the bulb, in effect.

In working with wiring on your train you should be care- ful but not fearful, for the strength of the current has been drastically reduced by the transformer. The 110-volt supply of your house is something to treat with great respect, for it can hurt you seriously. With your train set, however, the only place at which you deal with 110 volts is from the wall outlet through plug and wire leading to the transformer. After that, the voltage has been reduced to a mere15 or 18 volts. If you touch two wires or both rails with the current on, you will feel a sharp tickle and nothing more. You don't need to worry about short circuits because you probably have a circuit breaker on your transformer which shuts off the flow of current when a short occurs. Most transformers today are built with circuit breakers in them; if yours doesn't have one, buy a separate circuit breaker and connect it to your line according to the in- structions that come with it.

Despite the absence of danger with the current for model trains, be careful in the electrical work you do. As a mat- ter of general principle, everyone should handle with care a potential force as great as electricity, even when represented in one of its milder forms. In addition, careful wiring will give better performance and will last longer. There's no point in installing leaky or clogged pipes.

With a circle or oval of track, all you must do is attach the track terminal to the track at the most convenient spot. It clips on easily. Then connect a wire from one clip of the track terminal to the base post of your transformer, another wire from the other clip to the variable-voltage (7-15 or 7-18) post. The terminal itself has lettering to tell you which clip is which. Until you get some accessories, you do not use the fixed-voltage post (15 or 18 volts) on the transformer.

If you have disassembled the track frequently, it is a good idea to test it before running a train. While you're at it, you can test the transformer, too. (See Fig. 75.) With transformer plugged into the wall outlet, turn the control lever halfway on. Take the ends of the two wires from the posts on the transformer and brush the bared ends lightly together. If there is a spark, the transformer is all right. Current is flowing through it, as shown by the spark of a brief short circuit you intentionally caused.

Now to test the track (Fig 76). Again take the bared ends of the two wires from base and variable-voltage posts; hold one against one rail firmly and brush the other against the other rail. In this case a spark means trouble; it means that there is a short circuit somewhere along your track, and you must find it. The most common causes of shorts are metal objects lying across the tracks somewhere—nails, screwdrivers, locomotive, a piece of equipment. Sometimes, after long use, the gray fiber insulation between a tie and its rail will shift its position. If you find such a spot, pry up the tie clamps, slide the insulation back in place, tighten clamps again. If you still cannot locate a short, test each piece of track, each switch and crossing, separately in the same manner as before. It is an extremely rare occurrence, however, that comes only when track has been used a long time and not used well.

You do not need to test track or transformer when your train is being used regularly, of course. It is a good idea only when everything has been put away for a long time and you have just set it up again.

With transformer and track okay, track terminal and wires hooked up properly, you can run a train. If you have a large layout, you may find that the locomotive slows down perceptibly at some point far away from the track terminal. Perhaps it slows down because your floor or table is uneven and it has to climb a steep hill at that spot, but if the track is level, you are getting a voltage drop. The rails are extensions of wires, carrying current, but since they are not made of low-resistance copper, they do not allow the current to flow as readily and easily as wire; it loses some voltage as it moves through a good distance of rail. In small or medium-sized layouts the loss of voltage is  so slight as to be imperceptible, but on large pikes it may cause trouble. The trouble is easily remedied in about two minutes. Attach a second track terminal to the faraway spot on the tracks where the train slows down. Run wires from the first track terminal to the second, making certain that the two like posts are connected.

With this method, some current flows directly through copper wire to the far side of your layout and you get no voltage drop, no slow- ing down of the locomotive.

The first addition to a model railroad that most people make is a pair of switches along with a few sections of track. If they are manual switches, no wiring is necessary, of course. If they are electrical, remote-control switches, they must be wired, but the manufacturer has made this job easy enough for an eight-year-old. (See Fig. 77.) With the switches you will also get a small control box with two levers and four lights. One lever, one red light, and one green light are for each switch. Except for dead-end sidings, switches are usually installed in pairs, of course, so they are connected to a single control box.

From the control box extend two long cables, each consisting of four wires of different colors. These go to the two switches, where you attach the red wire to the red post, green wire to green post, and so on. From the other end of the control box two wires lead to the transformer, one to the base post and one to the fixed-voltage post, which handles the operation of most accessories. You will probably place the control box outside the ovals of track, near the transformer. This means, if you are running your trains on the floor or a table top, that you must slip the cables leading to switches beneath the track. See that they are flat and do not bend or curl up near the track so as to interfere with passing trains. Lights on both control box and switch show at a glance which way the switches are thrown—green for straight ahead, red for a turnout.

Next, you will probably add a remote-control uncoupler so that you can disconnect a car and leave it on a siding or an inner loop while the rest of your train pulls away to travel around the outer loop. It is a simple device that clips under a section of track anywhere you want to place it, as shown previously in Fig. 37. It has a control box, of course, as all remote-control accessories must have. This box, too, you will want near the transformer. From the control box there are two wires; one leads to the base post of the transformer, the other to the uncoupler. A third wire leads from the fixed-voltage post on the transformer to the uncoupler. It is as simple as that. Press the button on the control box as a car is passing over the uncoupling section of track and the car following will be detached from the train.

By this time you are accumulating a good deal of wire on the floor or train table, and you've barely started operations! You will want to get them out of sight and out of the way in some neat and orderly fashion just as you would want to if all the wires leading to fixtures and outlets in your house were exposed. With a table or train platform, you can do it easily. Drill small holes in the trainboard and run the wires underneath, to come up again through small holes beside the accessories they supply current for. This works all right so long as you have few accessories, but when your pike really begins to look like a railroad, the underside of your table will be a confusing maze. It need not be confusing if you use the "bus bar" system of wiring. This is really just a method of extending two posts of your transformer under the table, where they will be convenient for all accessories, no matter where you place them on your layout. You will appreciate having your posts lengthened, in effect, because they will have become so filled with clusters of bare ends of wires that you can't be sure they are all connected.

The two posts you will extend with the bus bars are the base post and the fixed-voltage post, which operates most accessories. The wires for bus bars should be considerably heavier than those on most of your accessories since they will  carry the heavy load of many electrical devices. Small wires set up resistance to the flow of current and cause voltage loss. The size of the wires depends upon the number of accessories you are likely to attach to them. If you plan only a few, No. 18 or No. 16 wire will do; if you will eventually have a big pike with many additions, use No. 14 wire, which is the size of cable in a great many houses. Buy single strands of wire in two colors. You need single strands so that you can splice into each easily. You need two colors so you can always tell, without tracing back, which bus- bar wire goes to the base post and which to the fixed-voltage post; black for base post, white for fixed-voltage post is customary.

How much wire do you need? If you have a 4' x 6' table, it will take six feet of wire to run down the center, plus a few more to reach the transformer—say eight or nine feet, If your table is 4' x 8' you will require two feet more of each wire. On wider layouts you may want to run the wire completely around the underside of the table, about a foot in from the edge, so as to put all accessories within easy reach. In a table only four feet wide, however, bus bars own the center are easily accessible.

You have probably located your transformer in a permanent spot on your table. Drill two holes in the table top below the base post and the fixed-voltage post on your transformer, so the bus-bar wires can lead from them to the underside of the table. If you have placed the trans- former on a shelf or separate stand off the trainboard, drill the holes in the apron or frame around the trainboard. If your board is a folding or hiding type, all you need to do is disconnect the two wires from the posts when you put the trains away.

The two bus-bar wires should run under the table a few inches apart (Fig. 78). Drill holes through supporting crosspieces, preferably, or staple the wires to the cross-pieces. It is best not to staple them to the bottom of the trainboard itself, as this makes them difficult to reach and work with when you must splice in accessory wires. The crosspieces may support the wires sufficiently, without their sagging, but if not, you can get insulated wire hangers from your hardware or electrical supply store.

Run the wires the length of the table—or around the edge for wide layouts—and tape the ends with friction tape. Do not connect them to each other or to anything else. You now have electric current beneath your table wherever you want it. How you connect accessories to the wires depends upon the nature of the accessories themselves. One basic principle can be established here, however. Wherever the instructions with an accessory say to hook a wire to the base post, you can splice it to the black bus bar instead.

When you are told to attach an accessory wire to the fixed-voltage post, you may attach it to the white bus bar instead. Accessories that have no remote-control boxes are the simplest to connect, as they have just two wires, one for each bus bar. This includes devices that merely light bulbs, such as some stations, floodlights, aircraft beacons, signal towers, and street lamps. Place the accessory in the desired position on the table, drill two small holes for wires to lead from its terminals to the underside of the table. There, splice the wires into the proper bus-bar wires. To make a good splice (Fig. 79), cut away an inch to an inch and a half of the insulation on the bus-bar wire and scrape it until nothing but clean, bare metal shows. Cut away and scrape for about the same length the ends of the smaller wires from the accessory. Now wind the end of each accessory wire tightly around the bared part of the proper bus bar wire. You must make this connection as tight as pos- sible in order to avoid setting up resistance to the flow of current. It must be secure enough to withstand the vibrations set up by running the trains.

The best splices, of course, are soldered, so if you have or can get a small soldering iron—the new gun type is easy to handle in small places—solder all electrical connections, using resin-core solder and flowing on just enough to encase the connection in metal. Most model railroaders do not have soldering irons, unless they've been at their hobby a long time. You can make good electrical connections without solder, but do the job carefully, saying to yourself that you will make each splice as tight as it would be with solder.

After the wires are spliced, wrap friction tape carefully around the connection to insulate it. If you wish, put some rubber splicing tape down first, then cover with friction tape. The new plastic electrical tape is excellent, and insulates perfectly, lies tight and flat; it is more expensivethan friction tape but on most model railroads you will use so little that the cost should make no difference.

Some accessories are made to function by the train itself rather than by remote-control buttons—such as crossing gates that lower when a train approaches, highway flasher warnings, and semaphore train signals used at switches or for making dead-block systems. The train can even be made to throw switches. Work of this kind is done by a pressure-type track trip, which looks something like a track terminal with three clips and a small adjusting wheel. The track trip is slipped under the track but is insulated from it, and it can be attached to either straight or curved sections. Two or three sections of track on either side of the trip must have their nails removed so they may rise a fraction of an inch. Inside the track trip is an electrical connection that is made when there is some pressure on the track, broken when there is no pressure; thus the track in that spot must be able to rise slightly and break the connection when no train is on it. As the train passes over, its weight depresses the track, makes the connection, and actuates the accessory to which it is attached. The little wheel can be adjusted so that the entire traineven the lightest car—will actuate it, as with crossing gates; with a different adjustment only the locomotive will make contact, as should be the case with semaphores and switches.

An example will show how the track trip is wired (Fig. 80). If you want it to actuate a crossing gate, place the track trip under the track about two feet to one side of the gate.

(If trains travel in both directions on this track, place one trip on either side.) One wire from the track trip goes to the fixed-voltage post on your transformer or, if you have a bus bar, to the proper wire beneath the table. A second wire from the track trip goes to a terminal on the crossing gate. The second terminal on the gate is connected by a third wire to the base post of the transformer, or to its bus bar beneath the table. Finally, the adjustment wheel is set so the entire train will close the circuit.

Now, when you send your train around the track, the gate will lower across the road as the train approaches, and will stay down until the last car has passed.

Never allow a train to stand for any length of time on a section of track with a track trip, even if the lever controlling your train is off. With the switch in the track trip closed by pressure of the train, current will continue to be fed into the accessory.

The wiring of all accessories using track trips is essen- tially the same; instructions that come with each are easy to follow. Even wiring track trips to switches is simple (Fig. 81). You need two track trips, one for the straight section, one for the turnout, so that trains coming in either direction will throw the switch if it happens to be closed against them. Wires lead from track trips to the switch and to the fixed-voltage post or its bus bar. On small layouts, track trips for switches are neither necessary nor desirable.

You can readily watch a small number of switches and throw them by hand or your remote-control levers. Only on large and complicated layouts being operated by one person are some switches likely to be forgotten or over- looked. In such cases track trips are advisable and helpful. On small layouts, moreover, the track trip is actuated so frequently by trains passing over it that switch coils may become overheated.

Finally we come to the type of accessory which is actu- ated by remote-control levers or buttons—switches, uncouplers, loading devices, action cars, talking stations, operating water tanks, whistles. (A whistle, incidentally,can also be made to work from a track trip so that it blows as a train approaches a station or crossing.)

More wires are involved in accessories using remote-control boxes because connection must be made not only be-tween the accessory and the power sources but also between accessory and control box. It is still a simple operation, however, as can be seen from the hookup of the uncoupler already described. Even switches, with more wires than any other accessory, present no problems to the beginner. With switches having selector buttons for Regular Opera- tion and Two-Train Operation, two trains may be run on
one track layout.

Another method of operating two trains at once, and one that gives you greater control, is to sectionalize your layout. As your pike becomes more extensive, you will no doubt want to install this system, by which different sections of track may be made to receive current or not, as you desire. This means that the different sections of track must be insulated from each other; fiber pins replacing the metal pins in the inside rails do this effectively. You can get fiber pins from your train store or manufacturer.

When you have insulated a section of track from the main line, you must see that it receives current directly from the transformer, which is done by a wire and a track terminal attached to the insulated section. But along this line you should place a switch that will allow current to flow to the insulated section or not, depending on how you throw the switch. Place another switch between the trans- former and the track terminal on the main line and you can control the flow of current to both sections of your track.

The simplest example of sectionalizing may be shown byan oval of track within another oval, the two being joined by switches forming a crossover  (Fig. 82). In the middle of the crossover you must replace the metal pin of the inside rail with a fiber pin. Attach a track terminal to the outer oval of track, making sure that the base-post terminal fits against the outside rail.

Run a wire from the base post of the transformer to this terminal. Run another wire from the variable-voltage post to the other clip on  the track terminal, but interrupt it at a convenient spot with a single-pole, single-throw switch—the simplest kind of toggle switch will do. A second wire, also with toggle switch, runs from the variable-voltage post to a single track terminal on the inner oval of track, making connection with the inside rail of that loop. Now both ovals have  common base rail but separately powered inside rails, each controlled by a switch. When both switches are on, current flows to all tracks. When the switch leading to the inner oval is turned off, no current flows to that oval but it still flows to the outer oval. Thus you can send current to both, none, or either one as you throw the switches. You can have trains traveling on both ovals or on only one.

If you have two transformers, or a transformer with twin controls, you may hook up one to the inner oval, another to the outer oval, and run two trains at different speeds.

But you will still need a fiber pin, as before. And you must make certain that your two transformers are correctly phased. Remember that, with alternating current, the current is continuously changing its direction of flow. Since each transformer is plugged into a different outlet, it is possible that you'll get the current moving one way in one transformer, the opposite way in the other, and both continuously changing to work contrary to each other. If you get a spark when the train passes from one oval to the other, merely reverse the outlet plug of one of them and both transformers will be in the same phase of current alternation.

Sectionalizing your track may be extended as much as you wish and, as your pike increases in size, you will per- haps make numerous sections, or "blocks." A long dead-end siding, with or without subsidiary sidings that make up a freight yard, is a good part of your layout to sectionalize.

Most very large layouts are sectionalized into blocks of different lengths, and switches are thrown for any blocks through which trains pass. With multiple-train operation, this arrangement is almost a necessity.

You can sectionalize your track by having the flow of current to each block handled automatically by track trips that also actuate semaphores. Each block is insulated with fiber pins, but the switch controlling the flow of current to it is actuated by a track trip in the next block (Fig. 83). If a train is in one block, for instance, its weight on the track trip has lowered the stop signal on the semaphore at the entrance to the block and at the same time cut off the flow of current to the block behind it. Any train entering that block will therefore come to a stop.

When the first train passes out of its block, the semaphore moves to Go position and current is supplied, so the stopped train starts up. With the dead-block system, a moving train always keeps the block behind it without current. No train can possibly crash into the rear of another.

When your model pike grows to some size you will probably want to incorporate into it a reverse loop or wye for turning the train around to move in the opposite direction. With a complicated layout you may even find yourself making a reverse loop without recognizing it as such in the maze of tracks. Then you will have a short circuit that you cannot locate or understand. With the installation of a reverse-loop relay, however, at the proper point, the loop will function without any short circuit and will add greatly to your enjoyment of your pike.

Why does a short circuit exist in a reverse loop without the relay or special wiring? If you look at the simplest form ofloop, in Fig. 84, you will see why. The outside rail becomes the inside rail as it completes its turn and enters the switch; this is just like touching one bare wire against an- ather as they come from the electric outlet. Obviously the rails in the loop must be insulated from the rails of the main line, and their polarity changed while the train is running on them.

 

When you plan a reverse loop you know just where it is, of course, and install the reverse-loop relay at the switch. But in a complex layout, you may have difficulty in locating it. In this case, draw a diagram of your layout, using a red pencil for outer rail, a black pencil for inner rail. Whenever you come to a point—it will always be at a switch—where red runs into black, there is the source of your difficulty. A reverse-loop relay must be installed at that switch, then the short circuit is eliminated and your trains will run without difficulty.

With two-rail track, reverse loops formerly had to be wired specially, with double-pole, double-throw switches, but all this has been eliminated by the reverse-loop relay, which handles the change of polarity in the loop automatically. It is a small metal box made to look like a wayside tool box on real railroads. Three wires lead from one side, four from the other, and are attached, as shown in Fig. 85, to track terminals at three points, and to the switch. Fiber pins replace the metal pins in rails of the loop, as shown and the selector button on the switch is moved to Two Train Operation.

Thereafter, your train can enter the loop, and when the switch is thrown to receive it back on the main line again, polarity of loop rails is reversed so the train can be received without a spark or short circuit Complete directions accompany the reverse-loop relay a it comes from the manufacturer.

The same principle applies to a wye, which you can make with three switches and several sections of track, as shown in Fig. 86. Fiber pins must replace metal pins at the points indicated, and the reverse-loop relay must be wired to the bottom switch just as it was wired above.

Long before you reach the point of making reverse loop and wyes you will have accumulated, in all likelihood, a number of switches and control boxes. They will look more orderly, be less likely to have loose wires, and enable you to operate accessories more quickly, if you mount- them on a control panel. Use a piece of Masonite or ply wood for the board, its size depending upon the number of boxes and switch levers you have, and are likely to have in the future. Leave room for expansion, always.

Lay out your controls on the panel, mark their positions with pencil, then drill holes to receive the wires from them. Place boxes in position and fasten with screws to the panel.

Connections are then made on the other side, and the panel can become the lid of a box which hides and keeps clean your electrical connections.

It is a good idea to arrange the controls in some reason- able order—levers for switches that are on the far side of the track at the top of the board, those on the near side at the bottom, controls for accessories on your right at the right side of the panel, and so on, so that controls are placed in more or less the same relative positions on the Panel as the accessories on the layout. The most realistic and professional handling of a control panel—but not an easy job—comes with laying out on the panel board an actual map of your pike (Fig. 87). Where you have a switch on your layout, place on your map the control for that switch. Spot the control for each accessory on your map in the position the accessory itself occupies on the layout.

The map system is particularly helpful if you have section - alized your layout; the switch sending power to each block is actually located in that block on your map. Such a panel is decorative as well as useful.

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