Hello, after many years of not being able to dive into N Scale I finally bought myself a Kato starter set. I'm quite excited to get the show on the road and I'm slowly buying all the parts for my planned layout. While testing out my V3 siding set I kept on having the track stutter while going over turnouts, I tried it again on a flat surface and the problems didn't come back but it got me thinking about polarity which is something I partly understand. If I plan to make the layout below, is it possible to run a train on the outside loop and one on the inside with DC? Also where would I place insulated and terminal joiners? Sorry if this is too many questions.
Yes it is. But I have been doing DCC so long I do not recall how to do it in DC. You will have some fun with that, but it will be addicting and want to get larger.
The double crossover already has internally isolated sections in it. So for your layout I think you can just connect it up and not have to put any isolated joiners in.
You have to ensure there is power at all four corners of the crossover. Kato switches are power routing, so if you have a switch down the line that is switched to another track and that leg is “dead” then the crossover may give you troubles. Recommend putting a feeder at each corner of it.
On DC ? As long as both trains are going the same direction it should not be a problem. The double crossover will result in an electrical fubar if the track directions are running opposite directions and a train tries to crossover. Its not a problem when running DCC.
Often, the safest thing to do, electrically, is to construct two different single crossovers with four separate turnouts. You then use insulated rail joiners on both rails at each crossover. The drawback to this can be track alignment changes that carry their own set of problems.
This is not an auto-reversing situation. The OP just wants to be able to run the outer loop, in the opposite direction from the inner loop. The double crossover's continuous outer rails will not matter in this layout, because they are each part of different loops. Really, this is good old DC block wiring, but if either of the "power packs" is or will be DCC, then you cannot use the "common ground" technique with SPDT (Single Pole Double Throw) switches, that is often used with DC-only layouts. Instead, you have to use DPDT switches, which switch both rails together to the selected power source. Again, you wire the two power sources to opposite-end terminals (one power source on each end) of the switches, and the rails to the center terminals of the switches. Since you only have two power sources and two blocks, only two DPDT (Double Pole Double Throw) switches are needed. Remember the switches select which power source powers their respective, attached track (block), not the other way around. This way, you can never have two power packs connected to the same track (which might not end well...)
