I know DCS like legacy can control conventional engines via varying the voltage to the track (duh, I know). This is where my lack of knowledge is going to be obvious. I went through the DCS manual, and here is what I got out of it:
1)If you want to run command only, use fixed input on TIU w 22 v into it, then connect the fixed output to the center rail via star wiring (ground obviously goes to outer rail)
2)If you want to run command and conventional (and this I am not too clear on), you power the variable input and the wire from the corresponding variable output goes to the third rail. First question: Do I need to bring voltage to the fixed input? My guess is no, but there is mention at one point of bridging between the variable and fixed input, hence my question. If running in command mode would I need to make sure that the variable output is at 22v?
One rub on this: So as I currently plan to wire it, I am going to wire a conventional transformer to blocks, with a toggle to select between A and B handle (ZW transformer), it may be a while before I have DCS in house for a number of reasons.
If I later want to use a TIU, would I put the output from Handle A into var input 1 and B into var input 2, and then put var output 1 onto the A side of each block toggle switch and var output 2 into the B side of each toggle switch? If you imagine two loops of track, I could envision running conventional engines on both loops, and I assume var output 1 would control 1 loop and var output 2 would control the other (with the toggle switch selecting for each block var 1 or var 2 and would address either variable output to control the voltage.
If I am right about this, then let's say I wanted to run conventional on 1 loop and command on the other. So loop1 is var 1, you vary the voltage. If I want to run a command engine on loop2, will the command base "see" the engine on there via var2 output channel, and I can just leave var 2 at 22 volts, and control the engine via command?
Hopefully this isn't too convoluted, in a nutshell the layout will be wired for standard block wiring using A/B selector switch and two handles of a transformer, but later on I want to wire DCS to run conventional (using both var channels on the tiu) and also allow conventional operation via either var channel, depending on where the engine is on the layout (no, I don't plan on having conventional and command on the same loop, if running command will be 22v full output, makes no sense to me otherwise).
And oh, yeah, this is just conceptual, when the time comes I fully plan acquire a copy of Barry's book (I think I actually have a copy on one of my machines) before attempting to hook it up or do any other foolish thing
