Switchmaster and Frog Wiring

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Allan Gartner and others:

I am taking your suggestions and am using Pilz Elite turnouts and Switchmaster machines w/RIX mounting blocks.

I wish to have facia mounted micro DPDT w/LED's to activate switch machines and to identify routing. Too, as per your Elite turnout wiring diagram, a toggle switch is required to provide a power routed frog.

1- With track power bus/feeders (10/18) and a switch machine power bus/feeders (18/22), is it possible to combine one toggle w/LED's to power switch machine and to activate power routed frog? If so, how?

2- Under Suggestion #14-6, you state "the Rix mounting block provides a convenient mount for your micro switches". Please help a DCC inexperienced HO railroad buff understand what this means and how accomplished.

To Allan and the many others who have contributed their DCC experience and skills by writing on the Web, I thank you. Your devoted efforts are indeed appreciated.

In advance, thank you for your response(s) to the above questions.

Bill Gaver

-- Bill Gaver (gaver@worldpath.net), November 11, 1998



Question 1. Wiring one toggle for switch machine and power routing. Yes. If you use a DPDT toggle, you can use one pole for the switch machine with the LEDs in series for activating the swithc machine and the second pole of the same switch is used for rounting the track bus connections to the frog. This works great if the frog is fully issolated as per recommended DCC friendly practice.

Question 2. The micro-switches are those little on off switches with the metal sprung levers that do the activation. They are sometimes used on doors for alarm activation etc. You place one each on the actuator arm bracket to the linkage on opposide sides. These allow for the actual turning motion to control the frog power and/or any signaling actuation. When you used N.O. (normally open) switches, the frog is powered only on the extended linkage arm at the final end of the travel. This method works for those non-DCC modified switches where the frog and closure rails follow the switch points (NOT recommended).

I prefer the DPDT method and fully DCC friendly switches for myself. But you can combine the methods and use the micro-switches as additional control and indicator contacts. -ed mccamey-

-- Ed McCamey (emccamey@cheerful.com), November 11, 1998.


The control panel / fascia mounted toggle switch has one purpose and that is to energize the the switch machine.

The power feed to the frog and the indication on the control panel MUST FOLLOW the action of the switch machine, not the action of the toggle switch.

A good machine, either a twin-coil type or a motor-drive, really should have @ least the following sets of contacts:

1) Large enough contact set to carry the track current to the frog. 2) A set of smaller contacts to energize the LED / light bulb at the control panel / fascia. Note: some of the older twin-coil types (Kimtron, Halmark) have two sets of smaller indication contacts plus the large frog power contacts.

By placing both the control of the frog power and indication at the toggle switch, you never really know if the switch machine actually moved.

Of course, the the linkage between the machine and the points must be realiable, no matter the case.

The use of additional micro-switches instead of switch machine contacts to provide indication adds another layer to the turnout setup (mounting, adjusting) and requires that some of the energy of the machine be waisted for moving the micro switch. The switch machine contact motion IS included in the design of the machine; the micro switch application may not be.

Personally, I use the twin-coil type switch machine, only the machine contacts and hinged points. I run the the machines at only 12 VAC.

No matter the choice between DC or DCC, I would recomment the use of a switch machine that comes with with frog power and indication contacts.


-- Mansfield (gofigure@zianet.com), November 18, 1998.

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