First point. If you are doing block sections then you need everything on the same set of blocks. So why not use one of the rails. You could then incorporate a secondary feed (catenary) into the set of block sections to run those locos at, say a different speed, but still function within the one set of block sections. But, is it really worth all the extra wiring. More than likely not.

If you want to run locos via catenary it is the same wiring as with a rail just 37mm higher! That's the only difference.

It is very simple to do block sections. No point having less than 3 block section.

If you want to do it automatically used the Marklin 8599 rail switch (or you could wire in a beam across the track). You can easily add overriding momentary switches on your control panel for each block section.

When the loco goes over the 8599 it briefly closes a circuit. This circuit you wire to a latching relay to "open" the circuit of the previous block and also to "close" the circuit of the latching relay for the block before that block section.

You need a latching relay for each of the block sections. So if you have 7 block sections, you need 7 latching relays. The opening and closing you wire to chase around the loop, easy.

I have set my mine up as effectively plug & play. If a relay were to fail (not likely) I simply plug a new one into a 16pin IC seat. The latching relay I used is double pole double throw, so very easy to wire in both open circuit for previous block section and closed for the block section before that, easy.


This wiring may look complex on the surface. But the only complexity is to make it simple. So if a switch or relay fails, I can simply plug in a new generic unit. All switch wiring is exactly the same. Each of the 1 to 8 switches are exactly the same. A have spares made up.


Knock up a 3 block section test loop to get your head around the wiring. You will eventually see the simplicity. Then whether you have 3 blocks or dozens, it will make sense, be patient, but you will get there.

Thanks for all your feedback.

After some searching, the track design software, in AnyRail in particular, wasn't built-in as catenary requires a lot of fiddling and tweaks - even in the real world.

So I'll take TooSmall's approach and design on paper. This requires having a few physical parts to design with.
Before I make the purchase, I have some catenary pieces that I manually moved around the layout, eye-balled, and penciled in to get an idea of how many pieces I would need to order.
I'll order a few extra for contingency.
The blue pen is track, the gray pencil is catenary.



This pencil layout was then transferred into AnyRail, I've also made the straights longer.



It allows for the train to automatically run from the inner to outer loop and vice versa. Works in both directions.
Max train length would be about 400mm so that there is no potential derailment when the points are switched.
I've marked catenary masts in by hand.
I've also marked the wiring with the coloured lines.
The brown rectangles will be the baseboard support beams.

And here is a mock-up of what the curved turnout section would look like:



BTW: I'm a beginner, just starting a small diorama with working track/switch/section. This catenary layout you see is something to play with/learn about whilst making the diorama - parts will be re-purposed once I get to making a proper layout.

Edited by user 15 November 2022 07:52:05(UTC)  | Reason: Add updates of design

A mock-up of how I did the track bed base and mast base. The white base is only about 50mm wide to allow for greater topography height variation. Plan your topography at the start. It is actually the original elevation which otherwise you will have to spend a lot of effort on with the excavators. Look at the landscape first.