converting 1122 switch to constant voltage

[steveflash]

I have seen reference made to Bob Nelson's advise in the forum on converting 1122 switch from track voltage to constant voltage but I can't find it.  Anyone know where I can find it?   Thanks.  Steveflash

[webenda]

For a Type S transformer Lionelsoni said, "Connect terminal U to the outside rails, A to the center rail, and C to the center wires of the controllers. Don't connect anything to the center terminals of the turnouts. This will give you 10-19 volts for the train and 19 volts all the time for the turnouts."

Reference: http://cs.trains.com/ctt/f/95/t/192167.aspx?sort=ASC&pi350=2

Other Lionelsoni posts on 1122 constant voltage wiring: http://cs.trains.com/ctt/f/95/p/187663/2050689.aspx#2050689 http://cs.trains.com/ctt/f/95/p/166790/1833122.aspx#1833122 http://cs.trains.com/ctt/f/95/p/192167/2097609.aspx#2097609 http://pictures.olsenstoy.com/cd/swt/stc1121a.pdf

Lionel LLC described the internal rewiring of 1122 switches in their Lionelllc blog: http://lionelllc.wordpress.com/projects-and-tips/wiring-your-layout/preparing-switches-for-constant-voltage/

There is also a video on youtube: Wiring Lionel Switches for Fixed Voltage: http://youtu.be/_0McntbmQ9I

Hope that helps.

[lionelsoni]

Thanks for digging up all those links, Wayne.

Let me add a warning that it's risky just to convert those O27 turnouts without other precautions.  The problem is that they lack the electrical switches that shut off the solenoids after the switch has thrown, which are present in the Lionel 022 turnouts, K-Line turnouts, and others.  So, if a train stops on the turnout, the anti-derailing feature will keep the solenoid on indefinitely, burning it out.  Powering the switch from the track voltage at least gives you a good chance that this will not happen.

There are two fixes.  One is simply to disconnect the control rails from the solenoids and do without the anti-derailing feature.  The other, which I use, is to power the switch with DC through a simple capacitive-discharge circuit, comprising a lamp and a capacitor.  This provides all the energy needed to throw the switch, but only for a very short time, nowhere near long enough to do any damage.