One problem with the KW is the arrangement of the fixed voltage taps. The 6 volts is reference to U or Common and the 14 volts is reference to the Hot (where A and B go at full power).
This limits it's applications in accessory control. Many Accesories are referenced to Common and require 12 to 14 volts to operate. Using the 14 volt terminal on these applies the full 20 volts. You can use the center taps for 14 volts but then you in essence have one common 6 volts above the track. This could lead to shorts and smoke.
If I were building what you suggest I would use A-U for one main and B-U for the other. I'd pick up a couple of 1033's for yard and accessories and use the CW-80 as a paper weight
Connect the KW's U terminal to the outside rails. Connect the KW's A terminal to the center rail. There are several ways to power your accessories:
From the KW, C-U for 6 volts, sharing a return with the track, not protected by the circuit breaker, probably too low voltage.
From the KW, D-U for 20 volts, sharing a return with the track, protected by the circuit breaker, probably too high voltage.
From the KW, D-C for 14 volts. not sharing a return with the track, protected by the circuit breaker, reasonable voltage for many accessories.
From the KW, B-U for 6 to 20 volts, sharing a return with the track, protected by the circuit breaker, adjustable to the best voltage for the accessories.
From a new-type CW80, A-U or B-U for 0 to 18 volts, sharing a return (U) with the track if you want.
From an old-type CW80, A-U or B-U for 0 to 18 volts, sharing a return (A and B) with the track if you want. )A and B are the transformer common. The two U terminals are not connected to each other.)
For a complete loop of the size you describe, I wonder whether you need any extra feeders at all, unless your track joints are in bad shape.
Bob Nelson
"Lionel trains are the standard of the world" - Jousha Lionel Cowen
I'll be using the KW, and I shouldent really worry about overloading this transformer, since I wont have more than 2 or 3 engines running at the same time, and I wont have passenger cars. As far as i know, the KW has an "A" and an "U" terminal.
Do you think that a postwar KW transformer will be enough to power track for a layout 10ft. x 15ft. with 2 mainlines and a yard?
It's not the size of the layout. Provided you use the bus wire techniques to reduce resistance. What matters is what you're running on the two mainlines and in the yard. And are you running everything together? With KW's And ZW's the ratings (which are optimistic) is the wattage of all terminals. As a kid I ran a Postwar NH EP-5 and a 2026 with a KW. As my layout grew and I added lighted passenger cars, etc. I finally needed to get multiple ZW's.
Generally, the outside rails are a common return for all the circuits, track and accessories. The transformer common connects to this. Transformers with more than one control usually use U for the common. Single-control transformers usually use U for the terminal that connects to the center rail. But there are exceptions. Let us know what transformer you have so that we can tell you what is what.
The lights and accessories do have at least two terminals. If you are running a third wire for constant accessory voltage, so that they do not turn off when the trains stops, connect them to that third wire and to the wire that feeds the outside rails.
If you have an accessory that you want to operate only when the train passes, insulate a short section of one outside rail and connect the accessory to that rather than the main outside rail. The train's wheels will connect that isolated "control" rail to the main outside rail and turn on the accessory. You can buy track sections that are already insulated for this purpose.
The outside-rail common-return side of the circuit is often called "ground". This is not literally true--it isn't really connected to ground unless you connected it. But it is a handy name; and it is at least a model of rails that really would be grounded in a prototypical electric railroad.
Note that the house-wiring cable that you might use has at least three wires, white, black, and a bare wire. You can use all three, one for the outside rails (perhaps the bare one), one for the center rail, and one for the accessories.
(I think it's best not to call the bus wires A, B, C, etc., until we know what transformer(s) are involved, since these letters are used for transformer terminals and mean different things on different transformers.)
("Buss" means "kiss".)
magicman710 wrote: Earl, how do you connect lights with two wires to one? Dont you have to 2 wires, one A and one B?
Earl, how do you connect lights with two wires to one? Dont you have to 2 wires, one A and one B?
One side of my lights connect to the 'C' buss wire. The other side of the lights connect to the ninth wire. A panel switch connects the ninth wire to the 'UC' buss wire. So when the panel switch is on, the ninth wire is connected to 'UC' and all lights are on. When the panel switch is off, the ninth wire is not connected to 'UC' and all lights are off.
Hope this helps...
Earl
So in other words, you can use to wires, one A, one B, and have it go around your layout, and connect the track with it, by connecting the A bus to the #1 clip, and the B bus to the #2 by using feeder wires from the bus, and to do it with accessories, you would do the same thing except with using the accessory posts on the transformer, right? I'm not very framiliar with electrical stuff, but Earl, how do you connect lights with two wires to one? Dont you have to 2 wires, one A and one B?
When I constructed my layout, I ran 9 bare wires from one end of the layout to the other end. Eight of the wires were connected to each of the eight terminals on my ZW. The ninth wire was used for the lighted accessories on the layout and controlled by a panel switch to turn on/off the lights. It was controlled by a panel switch to the UC wire. I used standard house wiring with the insulation removed. The wires made hooking up accessories and drops to the tracks very easy without having to run long wires.
A bus is a wire or set of wires (two in this case) that many things (in this case track) connect to. ("Bus"--not "buss"--is short for the Latin "omnibus", "to all".) I recommend at least 14 AWG, but 12 AWG is better. Anything smaller (larger AWG number) isn't much better than the track itself. If your transformer can put out 15 amperes, you need 14 AWG to be safe anyway, 12 AWG for 20 amperes. The wire can be solid or stranded. A convenient source is the non-metallic sheathed cable used for house wiring, which you can get at any home-improvement store.
The lockon wire I have seen is pretty small. If the distance is short, it doesn't have to be as heavy as the bus, but should not be very much smaller. A good choice for a few inches is 16 AWG.
Ok, i need to clear some things up. A buss wire is a wire that goes under the table to add power to the track every 5-10 feet, right? And you send 2 wires, one A and one B, or do you only send one of these as buss wires? What wire do you use to use as a buss wire? And will the wire that comes with lockons be fine to connect the buss wire to the track?
Thanks,
Grayson
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