Catenary on your layouts

hmm, that hadn't initially occurred to me. I'll have to think about that one. it might be possible to make a simple circuit that would only let the electricity flow the right way. My dad is an electrical engineer for spacecraft, i'm sure he has an idea.

green_elite_cab wrote:hmm, that hadn't initially occurred to me. I'll have to think about that one. it might be possible to make a simple circuit that would only let the electricity flow the right way. My dad is an electrical engineer for spacecraft, i'm sure he has an idea.

Yea, its called adding diodes. Even still that could be a bit trickey and would make the operation a bit more difficult as engines would still have to face one way to operate.

ApproachMedium wrote:

green_elite_cab wrote:hmm, that hadn't initially occurred to me. I'll have to think about that one. it might be possible to make a simple circuit that would only let the electricity flow the right way. My dad is an electrical engineer for spacecraft, i'm sure he has an idea.

Yea, its called adding diodes. Even still that could be a bit trickey and would make the operation a bit more difficult as engines would still have to face one way to operate.

In addition to diodes on Double pantograph Locos You could wire the Pantograph in reverse to the other pantograph. When the Loco is reversed you switch pantograpghs or for single pantograph locos install a physical switch (hands on approach)

ac0catenary wrote: Hey I remember you ! How are u doing ?
Well that is a yes and no question. On my railroad all the main running (4)tracks are insulated from each other.(reason: when I was on a Analog system I could used the catenary as a common to control individual tracks with individual powerpacks) YES it is possible to isolate a track and power it for a diesel or steam loco but for them to operate on the same track, NO it wont work. I use both rails for return power and that would short circuit out power for the diesel or steam loco

I'm fine. I see you're doing well

I've always had my track set up for block operation even though I run mostly DC (reason being; I actually switch back and fourth between DC and DCC operations based on what locomotive is assigned and whether it has a decoder or not).

I should have been a little more clear as I didn't expect the two to work on the same track. Would it be a simple matter of wiring the catenary powered lines and track powered lines like I would a DC and DCC system to an Atlas selctor switch? That's what it sounds like but I wouldn't be surprised if there were more to it.

I'm SO tearing this down to replace it with a better system, but i also only built it to gain experience. There are some kinks in the wire, and thats because a lamp i was using to take photos fell apart onto the wire, but its otherwise intact.

I have finally acquired some of those brass structural shapes to make some real nice scale catenary, but now i'm not so sure i want to. even if i do make it look good, does my little 4x8 justify catenary? I'm not so sure i could re-use any pieces i make, so i'm not sure if it's really worth it.

I'm also trying to build a 4-track NEC diorama thingy.

here are some pictures of what I've been working with.

The NEC one is far from complete, but i have some trains staged on it just for fun. there will be at least one more bridge in the back. I'm also using it as a way to learn how to "wire" intlockings and such. I'll be adding a crossover to the two middle tracks, and experimenting with building the box catenary and such.





On my layout-

A more costly approach to the problem is... instead of using diodes, can't you use DCC to control the direction of travel?

diburning wrote:A more costly approach to the problem is... instead of using diodes, can't you use DCC to control the direction of travel?

No because you still need a common rail neutral rail and the DCC signal/power rail. One has to go to the catenary and one needs to go to the wheels at one side or both. If you end up with the loco backwards you now could potentialy put double the voltage into the decoder and fry it.

ApproachMedium wrote:

diburning wrote:A more costly approach to the problem is... instead of using diodes, can't you use DCC to control the direction of travel?

No because you still need a common rail neutral rail and the DCC signal/power rail. One has to go to the catenary and one needs to go to the wheels at one side or both. If you end up with the loco backwards you now could potentialy put double the voltage into the decoder and fry it.

No, i think he means if you could use a the decoder to detect the direction of travel for the power going down the pantograph, and shutting off/switching it appropriately.

I really dont understand with my vast knowledge of DCC how that would work. Decoders dont detect directions of travel. They respond to packet information from a command station or respond to DC power of either positive or negative to provide a direction of movement in DC mode. If you ran DC from the catenary and did a positive or negative that way you would still have to have a rail setup that would hold the other end of the DC polairty and you could not run a DCC train on thouse rails. You also couldnt run a DC train on thouse rails unless the pantograph operating locomotives still, faced one way at all times!

ApproachMedium wrote:

diburning wrote:A more costly approach to the problem is... instead of using diodes, can't you use DCC to control the direction of travel?

No because you still need a common rail neutral rail and the DCC signal/power rail. One has to go to the catenary and one needs to go to the wheels at one side or both. If you end up with the loco backwards you now could potentialy put double the voltage into the decoder and fry it.

Well, If you weren't doing catenary, the DCC system would be hooked up on to the two rails. Instead of hooking up one of the wires from the command station to the rail, why not hook one to the track, and one to the catenary? You can run engines in any direction on DCC on the same track with 2 rails. I don't see how this won't work with one side hooked up to the catenary.

diburning wrote:

ApproachMedium wrote:

diburning wrote:A more costly approach to the problem is... instead of using diodes, can't you use DCC to control the direction of travel?

No because you still need a common rail neutral rail and the DCC signal/power rail. One has to go to the catenary and one needs to go to the wheels at one side or both. If you end up with the loco backwards you now could potentialy put double the voltage into the decoder and fry it.

Well, If you weren't doing catenary, the DCC system would be hooked up on to the two rails. Instead of hooking up one of the wires from the command station to the rail, why not hook one to the track, and one to the catenary? You can run engines in any direction on DCC on the same track with 2 rails. I don't see how this won't work with one side hooked up to the catenary.

Okay yes, this works. I know that. One rail, lets say the Red wire/Right rail to DCC RPs is the catenary. The Left rail/Black wire goes then to both of the two rails. Now, thats it all you can do is run DCC trains via catenary. You cannot have one rail be the black wire and one be the red wire and then the catenry being the red wire too. If you do, you still must keep a loco facing in one direction in order to run DCC 2 rail engines AND run catenary powered locomotives. The DCC only controls the direction of movement NOT the phsyical direction that you can place the catenary locomotive on the tracks. A DCC locomotive always has a right rail and left rail pickup to work and will always have a native forward direction. So double cab electrics would be fine in this situation.

If you just keep the two rails as the black wire as mentioned and the catenary as the Red wire then you can place the DCC catenary engines in any direction you so desire and they will run however you like, but as I said the 2 rails will then be the neutral and wont work for anything else other than an engine with pantograph collection.

Now if you want to save yourself of all this discussion just go buy a Marklin trainset. Catenary and non catenary engines can run on the same tracks at the same time even in digital thanks to their "center rail".

Ive discovered that there are many Northeast corridor layouts Lurking around Some with catenary some with out .. check my links page on PRRnortheast corridor.com and check out model memories Page They have added some layouts

New Pictures

ac0catenary wrote:Ive discovered that there are many Northeast corridor layouts Lurking around Some with catenary some with out .. check my links page on PRRnortheast corridor.com and check out model memories Page They have added some layouts

Thanks for sharing the pictures! Very cool stuff!

Here's the fixed link: http://prrnortheastcorridor.com/

Ive been hard at Work on the Layout .. Heres Some New Pictures of 30th street station and the High Line in Phlly
I only have one more Branch track to electrify. Ive been thinking about expanding to the Reading Railroad side of catenary through Broad Street Station Via a commuter tunnel to Wayne Junction since I take that route to/from Work. I have actually started on the commuter tunnel

I've finally got some of that better brass Structural shapes, but i have been stalled with putting it up. I'm not clear on a good way to make an assembly jig.