Wiring Conundrum

[pdxtrains]

I'm a sucker for gates, and just picked up pw 152 and am hooking it to my inner oval.  I'm using an insulated track, but just using the clip on doesn't give me enough volts unless the loco is flying down the tracks, which is too much.

I'm using an old KW, and the track variable A-U as usual.  I've tried connecting the gate as so: insulated clipon 2--> to the device, 1from device only, not the clipon, and into the transformer. I connect to the 14 volt fixed it's not enough juice, if I connect to the 20 volt fixed it SLAMS the gate down. I could connect to B, and use variable voltage, but I'm running a second train (A-B).

Here's my question: could I use an additional transformer for my line from device to transformer, and connect to a variable transformer connection (like A on the new transformer.)? It would look like this:

insulated track: clipon port #2 (which is fed by transformer 1) connected to device; no wire to clipon 1, but a wire from 1 to transformer #2, for variable voltage that I can set.

Would this blow up the planet, or is it possible?

Many thanks,

 

Thom

[lionelsoni]

Wire one terminal of the accessory to the insulated outside rail (the "control rail") that you want to activate it.  Wire the other terminal of the accessory to the voltage supply that you want to use to power the gate.  That power supply can be the center rail of the track.  It can also be a fixed voltage that shares a common return with the track.  If you have a suitable fixed voltage on the same transformer that powers the track, you can use that.  With a KW transformer using U as the common (connected to the outside rails generally) you have a choice of 6 volts at terminal C or 20 volts at terminal D.  (The KW has 14 volts available between terminals C and D, but not between either of these and the common terminal, U.  That 14 volts is therefore unavailable for any accessory operated by a control rail.)

If you use a separate transformer to power the accessory, connect its common to the layout common (the outside rails) and connect the second terminal of the accessory to the second transformer's terminal that gives you the voltage you want.

(Ignore advice to "phase" the transformers.  It doesn't matter.)

[gunrunnerjohn]

However, phasing the transformers in use on a layout is never a bad idea.

[lionelsoni]

Not a very bad idea; but, for an accessory transformer, it actually makes things a tiny bit worse, since out-of-phase return current from the accessory cancels some of the return current from the train, reducing the possible voltage drop in the outside rails.

[gunrunnerjohn]

Well, in that case, the thing to do would be to make sure they're "not" phased.

[lionelsoni]

It's usually not a big deal, either way.