Catenary Issues Update

Catenary Issues Update

By Roger Heid

 

Some time ago, I published a blog dealing with overhead catenaries. This blog is meant to be a follow up and update to the previous dissertation.

Since then, there were quite a few questions and some confusion regarding overhead catenary issues. One of the main concerns seems to be the question if overhead catenaries can be or should be powered in a digital environment.

It can be done, even though the majority of modelers advise against it. It is said that the connection between the pantograph and the catenary wires is not as reliable as picking up the power from the tracks. This depends on the quality of the catenary material used and on the tightness of the connections at the masts. Of course, it also depends on your craftsmanship.

Some catenaries tend to corrode or they are just too sloppy, in so many words. The configuration of the individual pantographs also comes into play. To make a powered overhead catenary system work reliably can take a lot of patience and some troubleshooting when things go awry. It can be quite tedious, indeed.

During the analog days, it was nice to be able to run two locomotives simultaneously on the same contiguous track. One would be a steamer or a diesel, the other one would be an electric locomotive getting the power from the catenaries. It was necessary to employ a second power transformer. Nowadays, on a digital layout, all this is not needed anymore. The catenary system can be used just for show only, thus making the set-up and the wiring much simpler.

Ernest has written a Blog about ‘Electrification and Modeling’. You should refer to this blog. In it he explains the ways the pantographs are used in the real world. There is more to it than what you initially thought or knew about this subject.

Currently, there is a model railroad industry trend whereby the pantographs on an Electric Locomotive are no longer wired to pick up electricity from overhead catenaries. This obviously follows the trend among model railroaders who have either gone digital or started out that way to begin with.

In addition, some of the newer electric locomotives allow you to raise and lower the individual pantographs via digital remote control, thus emulating real world operation. See Ernest’s blog.

title_EEE_31120_194_108_03   title_EEE_31033_151-018_03

ESU Models E 94 (left) and BR 151 (right). Both features remote pantograph raising and lowering.

He also explains that under certain conditions both pantographs are lowered on purpose. One situation would be if cars need to be coupled or uncoupled. The shift yard workers take a quick look at the pantographs. If they are down they know it is now safe to go about their business without the danger of being electrocuted.

Under certain other conditions, an electric locomotive may just coast for a stretch with both pantographs in the down position. Now imagine you have your catenaries powered. As soon as both catenaries are lowered you will lose control over the loco as it no longer receives the digital signal. It will just sit there, doing nothing until you manually raise at least one pantograph. This seems to defeat the purpose of the feature, don’t you think?

No, you will NOT supply the power to both, the track and the catenary system. Doing so can open a can of worms you would much rather keep closed. You could inadvertently apply double the voltage to the system which is something your decoders will not appreciate, at all, to say the least. Don’t try it. Theoretically, it can be done, but the complications do not justify the purpose.

Now that you have read all this you should be able to come to your own conclusions and make your own choice.

Please, do not post questions in the Blog System. Go to the Forum under the ‘Technical Corner’ topic. Thank you.

Happy Railroading!

One Response to Catenary Issues Update

  1. James R says:

    Right at the present time there are locos with more than one pantograph so that they can operate across different systems and voltages. How do they do this you may ask? They have battery backup to power the operating system and the correct pantograph to match the geographic location (GPS)

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