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Wiring a frog with a walthers switch machine Track and electrical/DCC
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Regular poster 335 posts taholmes160 Regular poster 335 posts
taholmes160

Hi Folks:

I have a handlaid switch, that I am planning to install using a Walthers Switch Machine.  The switch machine has 2 switches on it -- push buttons types.  each has 3 connectors from top to bottom.  NC, NO, C -- Normally Closed, Normally Open, and Common.  IM really not sure how to wire the lead coming down from the frog to those switches, to control the polarity of the frog.  Can someone please point me to a proper reference.

 
Thanks
TIM
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Prof_Klyzlr Moderator 7,967 posts
Prof_Klyzlr

Ignore the "normal"

Dear Tim, First up, the "normal" term implies there is a spring or similar which, everything else being equal, forces the electrical switch to a given position. The key here is to "forget normal" (in the electrical sense). There is no "normal", only "is the turnout thrown Straight or Diverging" (I'm deliberately avoiding the railroad term "Normal" as usually means "straight route" or "default routing" to head-off confusion). SO, 1 - In all conditions, the "common" ("C") terminal gets wired to the Frog (preferably with a green wire...why? Well, because frogs are green... ) 2 - When the turnout is physically thrown/aligned to the "Straight" route, Break out the multimeter and confirm which terminal "NC" or "NO" is connected/conducting to the "C" terminal (and thence to the frog) That terminal should be wired to the Curved-stockrail or matching Track-buss wire 3 - Now throw the turnout for the Diverging (Curved) route, and confirm that the Other "Nx" terminal is connected/conducting to the "C" terminal (and thence to the frog). Wire that terminal to the Straight-Stockrail or matching Track-buss wire. If it helps, think of the electrical Switch as being a "2-in, 1-out" situation, where the aim of the game is to select the correct track-buss-wire to connect to the frog at any given moment, as dictated by the physical throw-orientaion of the turnout. NB that you only have to use one of the micro-switches to power the Frog, the other can be left free to trigger signalling, turnout position feedback, or any other task... Hope this helps, Happy Modelling, Aim to Improve, Prof Klyzlr
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taholmes160 Regular poster 335 posts
taholmes160

Thank You

HI Prof:

Thanks a bunch, that makes sense, planning to wire that up this evening -- TIM
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