DCS / 2 Power Blocks (DCS) Isolate or Not?

First, as someone who also uses realtrax, I’m going to assume you’re using a lot of 30 inch sections and soldering track sections at the Center tab and/or wires connecting the center rail from section to section(after scraping off the black coating underneath)- time consuming yes but it really helps with the signal

regarding isolating districts: with DCS the TIU channel signal and power are intertwined b/c the DCS signal goes through the Center rail. So when isolating, you should consider both power and if you are using another TIU channel.

Instead of using the realtrax isolated section, I’d use a normal small straight but regardless is you use the Realtrax Isolated track piece the following approach works just as well. let’s assume you have two loops and they are connected by two Switches with the isolated track in between and you haven’t removed ANY wires from the isolated section . Also, even with the advice above implemented(I.e. soldering to decrease the number of track sections)- having that many sections would be too much for a single channel to transmit its signal. Thus, you should isolate the loops both in terms of POWER and CHANNEL output. Fixed 1 is powered by one handle of your Z4000 and Fixed 2 by the other handle. Use separate power for the switches. For that isolated section, bend the Center tab back on ONE side and put electrical tape over it to be safe, then hook it up between the switches. By doing this, you’ll have isolated the power sources from each other AND because you kept all wires in place and only blocked that section off on one end, it will continue to safely receive power from the other Z4000 handle. This eliminates both a dead spot in terms of power and signal. Further,  you’re keeping the DCS channel outputs from overlapping as the Center rail is only physically connected to one of your loops.

On the other hand, you don’t always have to do the above. I advise it only when you have 10 to 12 SEPARAtE sections of track(aka- 3 straight sections just put together are 3 separate sections, but if you solder the tabs between each section and run a wire on the middle rail between each section- you now have a single section of track).

Further flying in the face of everything I just said, on my main loop I have a switch going to an industrial yard area that has three Spurs. The yard is it’s own district(I guess?- it’s controlled by 2 toggle switches from the terminal board) but is on the same TIU channel and gets its power from the same 180w brick. It just doesn’t always need to be on

hope that helps

Can't quite count exactly from your photo, but it looks like you have ~30 Realtrax lock-ons and turnout controllers.  If those are with the stock incandescent bulbs, they draw about 1 WATT of power per bulb at 18V DCS track voltage.  So that's 30 Watts!  There have been a few OGR threads discussing LED replacements for the bulbs used in the MTH lock-ons/turnouts.  You should get between 5-10x power reduction going to LEDs.   As to whether (or not) 400 Watts of Z-4000 power is enough to power 10 engines is a matter for discussion.  All I'm saying is burning up ~30 Watts of Z-4000 power "just" to light up the lock-ons/turnout bulbs might be something to consider...

@StevefromPA posted:

First, as someone who also uses realtrax, I’m going to assume you’re using a lot of 30 inch sections and soldering track sections at the Center tab and/or wires connecting the center rail from section to section(after scraping off the black coating underneath)- time consuming yes but it really helps with the signal

regarding isolating districts: with DCS the TIU channel signal and power are intertwined b/c the DCS signal goes through the Center rail. So when isolating, you should consider both power and if you are using another TIU channel.

Instead of using the realtrax isolated section, I’d use a normal small straight but regardless is you use the Realtrax Isolated track piece the following approach works just as well. let’s assume you have two loops and they are connected by two Switches with the isolated track in between and you haven’t removed ANY wires from the isolated section . Also, even with the advice above implemented(I.e. soldering to decrease the number of track sections)- having that many sections would be too much for a single channel to transmit its signal. Thus, you should isolate the loops both in terms of POWER and CHANNEL output. Fixed 1 is powered by one handle of your Z4000 and Fixed 2 by the other handle. Use separate power for the switches. For that isolated section, bend the Center tab back on ONE side and put electrical tape over it to be safe, then hook it up between the switches. By doing this, you’ll have isolated the power sources from each other AND because you kept all wires in place and only blocked that section off on one end, it will continue to safely receive power from the other Z4000 handle. This eliminates both a dead spot in terms of power and signal. Further,  you’re keeping the DCS channel outputs from overlapping as the Center rail is only physically connected to one of your loops.

On the other hand, you don’t always have to do the above. I advise it only when you have 10 to 12 SEPARAtE sections of track(aka- 3 straight sections just put together are 3 separate sections, but if you solder the tabs between each section and run a wire on the middle rail between each section- you now have a single section of track).

Further flying in the face of everything I just said, on my main loop I have a switch going to an industrial yard area that has three Spurs. The yard is it’s own district(I guess?- it’s controlled by 2 toggle switches from the terminal board) but is on the same TIU channel and gets its power from the same 180w brick. It just doesn’t always need to be on

hope that helps

First - Thank you for taking the time to respond.  I'm sure this is so super simple that I'm being an idiot. 

The Z4000 is basically two transformers.  I've seperated the total track footage about 50 / 50 between two terminal blocks.

I want to power terminal block one from TIU fixed output one and Z4000 Track one // terminal block two from TIU fixed output two and Z4000 Track two.

Does there need to be isolation between the two sections powered by terminal block one and two or not?  If so is it total isolation? or just the center rail?

No problem! Just passing it forward- follow the advice/guidlines on how to keep the signal strong and, as with anything else, the more you utilize the system the more you understand it. once you get it down DCS is great. And, if you haven't already, definitely get Barry\s DCS Companion, 3rd edition- extremely useful

When you say "power terminal block one from TIU fixed output one and Z4000 Track one// terminal block two from TIU fixed output two and Z4000 Track two." does the bolded portion refer to the Z4000 transformer's own remote control track control system? If it is, while I am unfamiliar with how using the Z4000 track control feature and DCS together works, I do know that they can work together and you can create "Z4K" tracks on the DCS remote. But that's all I know, sorry, man. However, If you are not referring to that feature....

.....and are just referring to the Z4000's two main variable outputs controlled by the handles, then I can help. Happy you're using terminal blocks- helps keep things organized and is great for wiring a DCS layout.

Simple answer to your question: You just need to isolate the center rail you DON"T NEED TO/SHOULDN'T isolate the outer rails.

Explanation: Totally isolating the ground and hot isn't just unnecessary, it can also create problems with the non-derailing features of the switch, possible performance issues when engines crossover, and definitely wouldn't be advisable if you run TMCC/Legacy.

Hope that helps! Keep us posted on how things go!