Switching between DCS and conventional

Use a sturdy single pole double throw center off toggle switch for each track segment you want to control.  Wire the track to the center tab and the DCS power to one outside tab and conventional power to the other tab.  If you want indicator lights for power to the track wire one light tail to the track center tab and the other light tail to the common/outside rail.  It's easier to see the circuit if you draw your own diagram with the switch in hand.

The metal boxes in front center switch 8 of my divisions as described.  The indicator lights tell me when one of the PTC Resettable Fuses trips so I can clear a fault and reset the power.

I did this for TMCC/Legacy so am assuming it will work for DCS. I like you tend to like using the transformer for conventional control of locomotives.

I have the Z4000 transformer. I have one tap connected to a TPC400 then to a terminal bus that goes to various parts of the track. I have an extra pair power/common wires connected to the terminal bus that sits next to the second tap on the transfomer but not connected to it.

When  I want to run conventional I disconnect the power/common connection at the transformer that goes to the TPC400 and ?ground? wire to the Legacy command base, plug in the power/common wires for conventional control to the second tap (you can use the first tap also) and go. The wire to the command base must be disconnected so that command control engines can also operate in conventional mode.

I assume that the only difference between TMCC and DCS is the The TIU is in place of the TPC. As long as you don't have the TIU connected directly to track but through a terminal bus you can do the same thing.

Joe

I don't use a switch at all, no need. Place command engine on track, set transformer for 18v, pick up remote and run train.  Place conventional engine on track, run with transformer. Wires run from transformer thru fixed 1 on tiu, then to track. Works great, been doing it for 5 years...

That's the way I do it too.  Works perfectly.  That's what the fixed channel means: power in equals power out.  Vary the input, the output varies also.  Perfect for conventional trains, they don't even know the TIU is there.

There are days when I just don't want to deal with that remote.  The feel of that big transformer handle takes you back to being a kid again.

Thank you all for the replies.

I thought of just powering the TIU with a transformer and then using it to throttle the conventional,  However I was worried about any potential damage to the TIU using the transformer to vary power.   Since you all have been dong just that for a while I guess there is no problem with the TIU.  

Does it make any difference in what order you power everything up?  Do you power the TIU, then the transformer, etc?

Again, I am not an electronics guy and given the price of these things I am always a little leery of trying something unless I know it will work and not cause a problem.

Thanks,

Ed

I'm no expert either, I'd be interested to hear what Barry or Dave or Rod or one of the other experts have to say about harming the TIU.  I don't see how it could - fixed channel, power in equals power out.

It does mean putting running time on the TIU "unecessarily": it is sending DCS signal to the tracks when it is not needed by the conventional engines.

My TIU and Z4000 are plugged into an outlet that is controled through a wall switch, so they come on simultaneously.  With transformer throttle handle down at 0, obviously.

 I'd be interested to hear what Barry or Dave or Rod or one of the other experts have to say about harming the TIU

That's no problem at all.

The fixed channels appear to just go through a relay for switching, the only problem I see is if you're powering the TIU from that channel.

Why get all fancy when you can just toggle the transformer handle a couple of times and the engine will come up in conventional

Yup, I use the Remote 4000 to do it this way as a walk-around throttle.  Works well.  One can also use the DCS handheld to do the same ... it's in Barry's book I think.