mine are unpowered. I planned on powering them someday. I found that so far, the engines have no problem running over them unpowered. Maybe I will leave them that way?
If the layout is controlled with DCS it is no harder to power the frogs with DC than with AC track power. The hard part is insulating the frog area and soldering the power lead. The frog power is fed through a relay actuated by the same LCS signal that operates the Tortoise turnout machines.
My 2 rail layout is Legacy and LCS controlled. Track power is AC from a pair of ZW-L's. Many of the older Legacy and TMCC engines are not compatible with DC track power.
Am I correct that you use the combination of DC power and DCS command on your two rail layout? If so -- if and when you auto power route your frogs how will you accomplish it? Bet others considering that combination will be interested in your solution while choosing between DCS and DCC.
bob2 posted:I run straight DC, with Variacs, big capacitors, meters, and circuit protectors on input and output. And a big red light to remind me to turn it off.
I realize that no self-respecting model railroader can live without a reversing loop. I envy those with that kind of space - a 14 foot square chunk of basement just to turn a train? A dogbone is my dream layout - four tracks. Takes 14 x 30'. No desire at all to reverse train direction.
Right now it is four ovals. Still takes a lot of room.
I am going battery power in 2020. Still won't need a reversing loop.
I have often thought about using a Variac. I assume you are also using some petty hefty power resisters or do you just have a Variac followed by a bridge rectifier then a capacitor bank and do not go above 12 Volts on the variac for max power?
No - it turns out that a 12 volt step-down transformer must be fed with the Variac's 132 volt tap, and even then you only get 12 volts out of the bridge rectifier.
No need for resistors or transistor throttle - speed control is all reactive, and very smooth.
I am surprised and impressed that you have good speed control. Do you use a Pi filter (capacitor choke capacitor) after the bridge? What is the rating of capacitor/s? What is the current rating of the step down transformer; I surmise about 4A?
I'm running AC power from Lionel PH180 w bricks for my 2 rail loops. I bought 2 more and I've been too lazy to hook them up!
Fun? I suppose so, if you like that sorta thing. 
Bruce
Its kinda fun what happens when one asks a 2 rail question on a really good 3 rail forum! For all things relating to 2 rail DC control please contact Dallee Electronics and download their really well done wiring diagrams. Their boards are built like military grade electronics, some of my boards are over 40 years old or more. This includes their DC reverse loop controller (Trak-DTRL). They even use screw terminals for hooking up wires, what a concept! 
And just to feed the fire, ALL model railroading is fun, 2 rail, 3 rail, Z, N, HO, O, G, live steam outdoors, all of it is FUN! Russ
