Different transformers on separate tracks, all running conventional and DCS via Double Pole - Double Through switch.

I have a very similar operation. I don't think you have missed anything.  I would just mention to use the best DPDT switches. I used some from china, and they shorted out my DCS.  Other than that I have/had no operational problems...

These switches are good quality from Grainger.

@RWL posted:

..

Each of these three three power supply bricks will be wired thru a DPDT switch.
One side of the DPDT switch will send power, from the brick, thru its respective transformer controller.
The other side of the DPDT switch will send power, from the brick, directly to and thru a DCS Remote Commander receiver box.

Power will only, ever, be sent to either the Controller or the DCS Remote Commander box, but never both.

How these will be opperated:
1. When running any Lionel conventional, Lionel Lion Chief, or MTH non-DCS locomotives, the DPDT switch will be set to send power thru the transformer controller.

2. When running any MTH DCS locomotive, the DPDT switch will be set to run power thru the Remote Commander receiver box.

..

To be clear, is this the configuration?

That is, one pole of the DPDT switches "hot" and the other pole switches "common".  And the "hot" and "common" outputs of the Controller and the mating DCS Remote Commander are always tied together (e.g., at the track).

If so, when in DCS Remote Commander mode, the track voltage "back-drives" the output of an un-powered Controller.  I'm not saying this is good/bad...just asking for clarification.

Thank you for that information.
I did see that in my original wiring plan, so I made a correction.

My current plan, and this is currently working on a single loop of track, is to run power from the brick directly to bot controllers.
Each controller, is then wired to one or the other outer poles of the DPDT switch.
The center poles run of the DPDT switch, go out the track.

While both controllers would always be powered, only one can ever be connected to the track.

If you take your layout and move the DPDT switch to the downstream side of the controllers, you will have the layout of what I am currently using.

Thoughts?

Right.  Without descending into the technical muck, I'm happier with the revised configuration.

As you say, the penalty is both controllers are powered at the same time.  I measured the idle power some time back.  Memory not so good these days but seems it was just a few Watts a piece.  Do not have a ZW so don't know its idle power consumption.

You can usually find a center-off 3-position ON-OFF-ON DPDT for the same price and form-factor as a 2-position ON-ON DPDT.  This can be handy to quickly disconnect any power from the track without pulling cables or what have you.

Why not just connect the DCS-RC directly to the tracks and run it in passive mode?  You can add a 22uh choke to the center rail feed of the transformer to improve the DCS signal strength if you have issues.  Then there's no switching of power.

Two things.

1. I think it may have been from a scope photo you posted, but I believe at full-throttle the Z-controller puts out a chopped sine-wave vs. a brick's unadultered "pure" sine-wave.  The degradation to DCS signaling may be small but it surely doesn't help.

2. The pesky 22 uH inductor/DCS-choke, if needed, can be a nuisance to find in small quantities.  For a 100 Watt brick you'd want one rated at least 5 Amps...and essentially double that for the 180 Watt brick (again, if needed).  By the time you account for shipping, you might be coughing up $5 each.  YMMV.

By The Way, my assumption is this:

While the 180-Watt PowerHoue does put out 180 watts, the voltage stays at a maximum of 18, making it safe to run the PH-180 direct thru the Remote Commander receiver box, as explained above, and to the track, for DCS operation.

Would this be a correct (safe) assumption?

@stan2004 posted:

Right.  Without descending into the technical muck, I'm happier with the revised configuration.

As you say, the penalty is both controllers are powered at the same time.  I measured the idle power some time back.  Memory not so good these days but seems it was just a few Watts a piece.  Do not have a ZW so don't know its idle power consumption.

You can usually find a center-off 3-position ON-OFF-ON DPDT for the same price and form-factor as a 2-position ON-ON DPDT.  This can be handy to quickly disconnect any power from the track without pulling cables or what have you.

The DPDT switches that I am using are good quality 3-position On-Off-On switches, from Grainger.com.
And, yes, the center OFF position is a very handy Power Cut-Off feature.

@stan2004 posted:

To be clear, is this the configuration?

That is, one pole of the DPDT switches "hot" and the other pole switches "common".  And the "hot" and "common" outputs of the Controller and the mating DCS Remote Commander are always tied together (e.g., at the track).

If so, when in DCS Remote Commander mode, the track voltage "back-drives" the output of an un-powered Controller.  I'm not saying this is good/bad...just asking for clarification.

Here is an outside the box question:
When placing the DPDT switch between the power brick and two controllers as shown, the risk would be, as Stan mentioned above, the back flow of current thru the off-switched controller.
This is why my plan is to move the DPDT switch to the 

Would it be reasonable to consider the placement of some sort of directional flow diodes in the two wires coming out of each of the two controllers to the track?

That would allow current to travel only out to the track, and not back to the off-switched controller.

I am a mechanical guy, and am not that well versed in the details of what this might entail, so I put it out there for discussion among those of you who are  much more electrically inclined.

Roger

@RWL posted:

By The Way, my assumption is this:

While the 180-Watt PowerHoue does put out 180 watts, the voltage stays at a maximum of 18, making it safe to run the PH-180 direct thru the Remote Commander receiver box, as explained above, and to the track, for DCS operation.

Would this be a correct (safe) assumption?

No, the DCS-RC is designed for a maximum of 6 amps through the internal PCB connections. 

@RWL posted:

...

Would it be reasonable to consider the placement of some sort of directional flow diodes in the two wires coming out of each of the two controllers to the track?

That would allow current to travel only out to the track, and not back to the off-switched controller.

...

Problem is AC or Alternating Current alternates the direction of current flow 60-times per second to and from the track so to speak.  It is true that diodes block flow of current in one direction...but to allow AC current to flow to and from the track you need to insert a pair of diodes.  Unfortunately in doing so those same 2 diodes would allow current to flow backwards, i.e., from and to the track.

Separately, getting back to what GRJ mentioned about "passive mode".  I'll elaborate later but here are some quick sketches.

The DCS-RC is rated for 6 Amps maximum current flowing thru it (from the input barrel-coax connector to the output banana jacks).  Isn't it "amazing" how MTH's Z-1000 brick's 100 Watts matches?! 

But a 180W brick could exceed 6 Amps.  Hence the passive-mode configuration.

Passive-mode is shown on the left with and without the controller.  If this is getting too weird just say so.  Otherwise we can continue the discussion!

@stan2004 posted:

Two things.

1. I think it may have been from a scope photo you posted, but I believe at full-throttle the Z-controller puts out a chopped sine-wave vs. a brick's unadultered "pure" sine-wave.  The degradation to DCS signaling may be small but it surely doesn't help.

2. The pesky 22 uH inductor/DCS-choke, if needed, can be a nuisance to find in small quantities.  For a 100 Watt brick you'd want one rated at least 5 Amps...and essentially double that for the 180 Watt brick (again, if needed).  By the time you account for shipping, you might be coughing up $5 each.  YMMV.

1. Connect directly to the brick.  You are correct, all the Z controllers are simple triac power controls. 

2. True, but is $5-6 really a major impediment?  If so, I'm in the wrong hobby.

The passive connection simplifies the connections, no switching needed, the DCS signal is there when you want it.

@stan2004 posted:

Problem is AC or Alternating Current alternates the direction of current flow 60-times per second to and from the track so to speak.  It is true that diodes block flow of current in one direction...but to allow AC current to flow to and from the track you need to insert a pair of diodes.  Unfortunately in doing so those same 2 diodes would allow current to flow backwards, i.e., from and to the track.

Separately, getting back to what GRJ mentioned about "passive mode".  I'll elaborate later but here are some quick sketches.

The DCS-RC is rated for 6 Amps maximum current flowing thru it (from the input barrel-coax connector to the output banana jacks).  Isn't it "amazing" how MTH's Z-1000 brick's 100 Watts matches?! 

But a 180W brick could exceed 6 Amps.  Hence the passive-mode configuration.

Passive-mode is shown on the left with and without the controller.  If this is getting too weird just say so.  Otherwise we can continue the discussion!

 

This is not getting weird at all.
I love to learn, and the answers are very good and clear.
I am also more than happy to continue this discussion, as it has opened up a whole new realm of understanding for me.
Again, this is my first true layout, and I want to build it the beast that I can, within financial reason.

I am very glad to learn about the 6 amp max for the DCS system, and am very glad I asked that question, or I may have caused some severe damage.

So, running in passive mode turns the DCS RC box into a signal entry point only, with power always coming from the transformer and thru the controller. Correct?

My Questions:
1) What does the 22uh choke do?
       Does it keep any of the DCS signal from back feeding to the controller?
2) Do the controllers effect the wave pattern in a negative way with regard to the DCS signal?
3) Do I need to measure where 16 and 18 volts, to the track, is on each controller, so that I can know where to set the controller for either Lionel-Lion Chief or for MTH-DCS locomotives?
4) Is there any way to limit the Amperage coming out of the 180 watt PH bricks?
       Probably not, but I have to ask.

No, passive mode connects ONLY the output terminals to the track, nothing is plugged into the input jack.  This allows the DCS-RC to inject the DCS signal onto the tracks, but no transformer current actually pass through the DCS-RC itself.

The 22uh choke in the transformer lead to the track keeps the transformer from attenuating the DCS 3.27mhz track signal.

The sawtooth waveform is not exactly good for the DCS signal, but many people do run that way.  In addition, when running DCS on the tracks, one would presume you'd be at full throttle, that yields close to a standard sine wave.

You can run DCS and LC/LC+ on up to 19 volts on the track.  No need to do measurements.

You can obviously put a smaller fuse or circuit breaker in series with the PH180 output, but I don't see a reason to do that.

John,

Very cool, so whenever running Lion Chief or DCS, just run the controller close to full power.
Yes, DCS box become just a place to inject the signal.

I have some of these chokes, that I ordered awhile back, for installing in the hot side of the transformer to track wiring, for just keeping the DCS signal clean. I think it is the same issue here, but just want to verify:

22uh 11A choke

Is this the correct choke for this application?
Would this work for both the ZW 180s and the Z-1000?

Correct that is a perfect match, AAMOF it's the one I use.  It will work for any transformer. 

Obviously, a pure sine wave is better for DCS, but if you use just the Z-1000 brick or have the Z-Controller full throttle, it'll be similar to a full-wave.

I guess I am missing something. How is the DCS-RC powered in passive mode?

Back fed from the transformer power in the track.