Here is a basic wiring diagram that shows how:
The attached drawing is a general depiction, so let me elaborate a little.
Note each handle of the Z4000 feeds one fixed TIU input.
Note if you are using a Z-4000, the ammeters and voltmeters are not needed, as the Z-4000 already has these.
Nor do you need to add the inline fuses at the Z-4000 or any modern day brick, because they already have a 10 amp CB on each output.
You should definitely install the TVS's though, right across the outputs as shown. They are PN 576-1.5KES36CA and have a clipping level of about 30 volts; available through Mouser electronics; about 45 cents a piece.
Wire the transformer to the TIU, red (hot) to red, black (common) to black using #14 wire as shown.
Wire the TIU outputs to the distr’n blocks using #14 wire, red to red, black to black. You can use the MTH 50-1014 distribution blocks as shown, or barrier type terminal strips as desired.
It is best if your distribution blocks are located roughly in the center geographically of the power district that each serves.
Wire the track feeds from the distribution blocks as shown using #16 wire, red to center rail, black to outside rails, for runs up to 25 feet long.
The bulbs shown can be attached right at the TIU output posts. 18 volt bulbs such as #432 or #1445 work well here. They provide DCS signal enhancement. It doesn't get much easier than this.
For your yard sidings, run one wire from the hot (red) side of a distribution block to one terminal of the first toggle switch. Jumper this wire to one terminal of each of the other toggle switches as well. You now have a common hot to one side of each switch.
Now run a hot wire from the other terminal of each switch to the center rail of each siding.
Insulate the center rail of each siding from the main track, right at the switch.
Wire the outside rail feed from each siding back to the common side of the distribution block.
The feed wires to the track feeds do not need to be the same length; only the length required in each case. But they should be wire pairs; a hot and a common wire to each feed.
The size of your loops will determine the number of feeds.
Usually a feed every 15 feet of track, or every 10-12 track joints is adequate.
Each TIU channel can feed up to about 150 feet of track total, and still get good DCS signal strength.
If your loops are small and there will only be 2 or 3 track feeds, you can use wire nuts in place of the distribution blocks.
Rod
