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Switch Wiring Question

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Posted by lionelsoni on Monday, January 16, 2006 8:17 AM
A single-pole-double-throw electrical switch for each block, which can be mounted on a simplified map of the layout if you like. Each switch connects the center rail of its block to one or the other of the transformers, which have a common return connected to all the outside rails. A center-off switch will also let you shut off a block completely.

To ron between blocks, you simply set both blocks to the same transformer and drive safely across the gap. Even with only two loops, it can be handy to divide each loop into more than one block so that two trains can swap loops without interfering with each other. For more than two transformer controls, you can use pairs of simple switches (one SPDT and one DPDT, for example) or rotary switches with more than two positions. It is even possible to handle as many as eight transformers with sets of three readily available toggle switches (one SPDT and two 3PDT).

Bob Nelson

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Posted by Anonymous on Monday, January 16, 2006 5:22 AM
What's the "simple alternative"?
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Posted by lionelsoni on Sunday, January 15, 2006 9:35 AM
Having the same common and being "phased" (in phase) are not the same thing.

Running between blocks powered by different transformer controls is very popular but can be dangerous. If the voltages are different between the blocks, as has been recommended above, a fault current will flow through the pickups as you cross the gap. This is no different from the fault current that would flow through a short circuit from a transformer set to a voltage equal to the voltage difference. If you are using two different transformers, the circuit breakers probably will not have time to trip. If you are using two controls from the same transformer, they will never trip, no matter how much current is drawn. This is of course dangerous if the fault persists for any length of time.

It occurs to me that the numerous complaints that are posted about modern locomotives with fried electronics might have something to do with this practice, since intermittent short circuits are an excellent way to generate the voltage spikes that are probably zotting them.

There is a simple alternative.

Bob Nelson

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Posted by Chris F on Saturday, January 14, 2006 11:22 AM
As a starter, here's a copy of the manual for current Lionel O-22 switches:
http://www.lionel.com/products/productnavigator/InstructionManuals/71-4062-250.pdf

Note that the manual indicates the two transformers have the same common (i.e., they are phased). Do a search on "phasing" and you'll find plenty of info here.

You also will need insulating pins for the center rail where the two switches are connected.
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Posted by Anonymous on Friday, January 13, 2006 6:32 PM
I will be using the 022 Lionels.
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Posted by phillyreading on Friday, January 13, 2006 11:06 AM
Before I can help you, what kind of switches are you using? Lionel, Ross Custom, GarGraves, K-Line, MTH? Make ure to use insulating pins on the center rails for sure!!
Lee in South FL
Interested in southest Pennsylvania railroads; Reading & Northern, Reading Company, Reading Lines, Philadelphia & Reading.
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Posted by Anonymous on Tuesday, January 10, 2006 4:14 PM
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Posted by Anonymous on Tuesday, January 10, 2006 4:13 PM
...
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Posted by Anonymous on Tuesday, January 10, 2006 3:25 PM
I've wired switches 'back to back' to enable crossing to another track. As the earlier post commented, insulate i.e. isolated the switches well. The real problem will appear when you run stock over the rails and switches. The derail feaure in the 022 may surprise you. So....wire the switches to posts so that you can easily change polarity. Don't wire adjacent switches in tandem, the derail feature may not like that! The bottom line, adjacent switches behave in strange ways (to me) so be prepared but don't give up!
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Posted by otftch on Sunday, January 8, 2006 4:13 PM
I've done this a few times.Just insulate the rails(I insulate all three) from each other.You have to make sure the transformers on both tracks are at approximately the same voltage to avoid runaway trains.This is one of the joys of "three railing".the e-units will not cause the problems you have in two rail track systems.I usually try to set the transformer on the track that is receiving the train set at a lower setting.You can always speed up later.Try putting a least a short section of track between the switches so if you use the de-railing feature you have room to work and don't have to modify the switch itself.I also run wires to all the ground (outside rails) on both sides of each track to prevent dead spots.
NOTE: make sure you use two different crossovers so you get back on to the track you started from.
Ed
"Thou must maintaineth thy airspeed lest the ground reach up and smite thee."
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Posted by Anonymous on Sunday, January 8, 2006 7:52 AM
Ooops. See this is already covered in another recent post. And,.....it's stil making my head hurt. Guess I will wait for the 'new' wiring book to arrive. I bought one but failed to look close enough and turns out it's an HO two rail book for the most part.
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Switch Wiring Question
Posted by Anonymous on Sunday, January 8, 2006 7:45 AM
In my planned layout I will be running two loops with one train in each. I plant to use 2 switches in-line (one in each loop) to permit the trains to cross from one loop to the other. I plan to power the switches with separate power (not track). What kind of insulating or other electrical considerations should be made here?

Thanks

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