Catenary

In looking through the Märklin catalogue, you will notice that several locomotives have unusual devices on their roofs pressing up against overhead wires. These devices are called pantographs, and the overhead wires are called catenary.  Together, they allow you to operate two Z-Scale locomotives on the same track circuit.

Take a look at the locomotives first. Somewhere on the roof, you will see an opening which has a straight slot screw head below it. This screw head can be turned to one of two points (many times marked U and O in small lettering).  Turning this one direction or the other determines whether the locomotive will operate from both rails or from the overhead and one rail. If you place the electric locomotive on the tracks, both the catenary and track transformers will operate the locomotive; if you turn the locomotive around 180 degrees, and if the overhead switch is set correctly and the pantographs are raised, only one transformer will control the engine.  You may be confused at this point, but I think that things will become clearer as we go on.  The catenary can be, well, fussy when you are installing and maintaining it, so you will need some patience with it. Don't let this scare you, since the system's design makes it easy to install once you understand what it does.  The elements of Märklin’s catenary system are:

Catenary Components

  • 8911 Basic Mast - This is the basic mast used with the Märklin catenary.  The mast is made of plastic with a wire loop and a wire hook which hold the catenary wire itself.
  • 8912 Feeder mast - Similar to the 8911, this mast provides electrical connection between the transformer and the overhead wire.
  • 8913 Bridge Mast - Also similar to the 8911, the 8913 is designed to attach to the Märklin bridges and ramps.
  • 8914 Support Mast - The 8914 is a tower mast, designed to be used in pairs,  which supports cross span wires.
  • 8922 Wire Section - This wire is 165 mm in length, used over both straight and curved track.
  • 8923 Wire Section - This wire is adjustable in length between 150 mm to 180 mm, used over both straight and curved track.
  • 8924 Cross Span - This wire piece is attached to two 8914 masts and spans up to 5 tracks.
  • 8925 Cross Span - This wire piece is attached to two 8914 masts and spans up to three tracks.
  • 8921 Catenary Insulators - These pieces are used with the Cross Spans; each package contains 8 white insulators (for joining two wires) and 2 gray insulators (for joining three wires).
  • 8926 Separator Clips & Connecting Springs - These are used at to join three  wires together at a turnout.  The clip can be used to create an isolation section in the catenary, with the spring being used if this is not desired.
  • 8927 Catenary Terminal Clips - these are used for feeding power to catenary sections if the 8911 cannot be used.

Installing the Catenary

Installation of the overhead system involves some trial and error, so patience is a real virtue. I prefer to start at a turnout.  Locate the mast base a short distance from the single end of the turnout, then take the mast and slide it into the base.  If you want, you can drive a spike into the base to hold everything in place. Spiking your track only partially, proceed down the straight track away from the turnout a distance approximating the length of overhead wire.

The basic mast is the 8911.  This mast has a metal base, plastic mast structure, and metal hangers. The base is installed at the same time as the track.  I suggest that you initially drive your spikes only halfway when installing the track so that the spikes can be removed easily if it is necessary to adjust the position of the mast base.

8911, Courtesy Märklin

Note that a small portion slides over the edge of the crossties of the track as well, giving you an extra measure of rigidity.  The mast hangers are spring wire; the lower one has a loop arrangement, while the upper hanger has a hook.

Courtesy Märklin

Courtesy Märklin

With the mounting plate located under the track, the mast is fitted into the base and gently pushed toward the track.  The base of the mast fits over the top of the crossties.

8912, Courtesy Märklin

Courtesy Märklin

The 8912 mast, which appears to be identical to the 8911 is the feeder mast and connects to the transformer; note that this mast has a brown wire, an important point in understanding catenary operation.

The 8913 mast allows you to attach the overhead wire to the Märklin bridges. Faller offers an attachment for their bridges that allows you to set up the Märklin catenary, using an 8911 mast that has been modified by cutting its base.

8913, Courtesy Märklin

Span Wires

If you have double track sections or yards with overhead wire, you need the 8914 mast.  

The 8914 mast does not have hangers on it; rather, you place the masts on each side of the tracks with either an 8924 or 8925 Cross Span wires mounted between them.

8914, Courtesy Märklin

The 8924 span wire will serve up to 5 tracks; the 8925 span wire will serve up to 3 tracks.  Note the small hooks at the top corners of the span wire, which fit into the tops of the 8914 mast.  The small protrusion on the side fits into the side of the mast.

8924, Courtesy Märklin

8925, Courtesy Märklin

The span wire is then fitted into two 8914’s.  Once the span wire is in place, 8921 clips are fitted into the span wire and the catenary wires are connected.

8921

Courtesy Märklin

Then, 8921 hangers are twisted into the span wire, over the rails (1). The white hangers hold two wires, while the gray pieces hold three wires. Once the insulator is placed, the wires are placed in the insulator (2) and the latch of the insulator is folded over and clipped shut to hold the wires securely in place (3). Note that these hangers can slide sideways in the cross span, allowing for adjustment over the various track centers. Also note that a large span may sometimes be used even with only two tracks, such as in a station.

Courtesy Märklin

Catenary Wires

There are two types of overhead wire. The 8922 is 165 mm long, while the 8923 adjusts from 150 to 180 mm. Both pieces have loops at each end which are attached to either the wire hangers of the 8911, 8912, and 8913, or to the lugs cast in the 8921 hangers.

Courtesy Märklin

Fitting Catenary Wires

Once you have positioned the first mast, position the second base using a wire piece to help you find an approximate location.  Go back to the first mast and mount the overhead wire piece. The bottom portion of the wire, the part closest to the rails, is straight, while the top of the wire piece is gracefully curved from one end to the other.  The loops at the end of the wire are slipped over the wire hangers of a mast or into a catenary insulator.  A pair of tweezers and an optical magnifier will prove to be of value here.  The tweezers are used to slightly compress the loop end of the lower wire hanger and the lower loop of the wire is slipped over the hanger. As you release the pressure on the loop hanger of the mast, the hanger will grasp the lower loop of the overhead wire.

When adding the next section of overhead wire, the tweezers are used primarily to guide the wire onto the first mast. The wire is gently lifted so that the upper loop of the wire is hung on the hook of the upper wire hanger. Go to the other end of the wire, mount the base, and adjust the distance of the masts so that it corresponds to the length of the wire. If the masts are too close together, the wire will be excessively bowed to one side or the other. If the masts are too far apart, the mast will be bent.

Here, the advantages of the 8923 wire become obvious, since the masts can be installed anywhere between 150 and 180 mm apart.  This is quite useful because you cannot always place the masts in the exact spot you need for the fixed length of wire.  At each mast, the second wire is added in the same fashion as the first, with the lower wire loop being slipped over the loop hanger and the upper wire being hung on the hook hanger.  Notice that the wire system keeps the wire in alignment with the center of the track, and that the wire should follow the center of the track as closely as possible.  The same wires are used on curved tracks and some gentle bending with your fingers will be necessary for the wires to follow the center line of the track. This is the trial & error I spoke about earlier, and the only way to determine if the wire is located properly is to run a locomotive with the pantograph raised.

Masts that are located at turnouts have three wires attached to them, and need a piece of 8926 to hold them together.  The 8926 is then attached to the 8911 catenary mast by means of the two vertical slots in the 8926.

Individual 8926 and connecting spring.

The 8926 piece has two sets of lugs.  Each set of lugs is meant to hold one or two wires.  If you do not want the 8926 to act as an insulator, use the small piece of metal included with the 8926 pieces to electrically bridge the wire sections.

 Once the wires have been positioned in the 8926, the strap segment of the piece is folded over the wires and snapped in place.  The two sets of lugs are not connected, so the 8926 can function as an insulator that divides the overhead wire into different electrical circuits in the same way that insulated rail joiners do.

Certain situations call for the 8927 screw clip:

Catenary Sets

You may also have noticed that, like the track sets, there are sets that contain overhead wire parts. The 8198 overhead system kit for S & E has enough wire to outfit the track that comes with the starter set and with the E expansion set. The 8199 overhead system kit contains enough materials to equip all the tracks of the T1, T2, and T3 expanders.  Although  you may not be building your layout to the design of the track expander sets, the overhead wire sets may prove to be helpful since all the different parts are included in the set.  Even if you run out of a specific part, you will be familiar with which parts you need to obtain.

8198, Courtesy Märklin

8199, Courtesy Märklin

Wiring Catenary

There are distinct advantages to the overhead wire system.  You can run two locomotives on the same track using two different transformers.  The wiring is really fairly simple, with the red connections of each transformer joined together and attached to the terminal of the 8590 feeder track. One transformer connects its brown wire to the other terminal of the feeder track. The second transformer connects its brown wire to the brown wire of the overhead feeder mast. 

In cases of multiple track with span wires, the 8927 catenary wire terminal can be attached to the various catenary wires (but not to the span wires). The wire from this terminal is then threaded along the span wire, and then down the 8914 mast. This is not as clean in appearance as the 8912 feeder mast, but it allows you to establish overhead power circuits where you need them.

It is important to make the proper connections:

Note that the two transformers both are connected to the “red” rail of the track. This is especially important if you are using automatic signals, which use the red rail to control train movement.  In this way, both locomotives can be controlled by the signals.

Obviously, the locomotive using the catenary for its power source has to be an electric, while the other locomotive can be steam, diesel or electric.  In the case of the second electric locomotive, it may have its pantograph touching the wire but it is getting its electricity from both rails.

You may discover that the locomotive which is set to operate from the catenary will run when either transformer is turned on; simply take the locomotive off of the tracks and turn it around 180° so that the proper pickup wheels are on the brown rail.

Pantographs

Finally, the older-style pantograph, when raised, is a box-shaped device, while the newer design of pantograph (also called a Faiveley type) looks like an arm extending up to the wire.  This pantograph, in operation, needs overhead wire which is adjusted to closer tolerances.  Again, a little trial and error will be necessary. Both pantographs rise and fall as the wire height varies.  Real railroads normally operate their locomotives with just one pantograph raised, usually the rear one.  The rear pantograph is used so that if it becomes damaged, the front pantograph remains intact. The front pan (pantograph) can be raised and the train can continue.  Many times, the damage to pantographs results in the pan being ripped from its mounts, and then skittering merrily along the roofs of the train's cars.  Keeping the front collector in reserve allows the train crew to stop, cut the power, remove the damaged pan, turn the power back on, and proceed to their destination. You may want to use both pantographs at the same time, since electrical pickup will be better and operation smoother.

Märklin made a few passenger cars with internal lighting. If you have these cars, you can allow the track voltage to stay on, leaving the cars brightly lit, while the locomotive can be controlled from the overhead wire. Or, with planning, a train can enter a station, and another locomotive can approach the rear of the train to remove or add extra cars. In any case, using overhead wires provides more operator control and interest.  It is worth the extra effort.

By now, it has become apparent that the steps you have taken for quality control are paying off in terms of reliable operation. When the layout support is built well, and the track and catenary installed properly, your own satisfaction is increased.

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