Ever wanted to automate the turnouts on your layout? Maybe you have some that are hard to reach? Or maybe you have a hidden staging yard? Do you model a modern CTC-controlled subdivision and want to give your dispatcher realistic control over the turnouts? Or maybe you have a multi-deck layout and other switch machines are too bulky to sit below the upper decks? No matter what the situation, MRServo is a cost-effective solution!
What is MRServo?
MRServo is a low-cost, low-profile, slow motion model railroad switch machine using small and inexpensive RC servos to control the turnouts on your layout. Three options are available to suit almost any situation. The first, MRServo-1, is the simplest and least expensive. It does its job of controlling the turnout, and does it well, without any bells or whistles. MRServo-2 and MRServo-3 provide extra features in the form of accessory contacts. With two sets of accessory contacts (DPDT form), the MRServo-2 is well suited for simple power routing and integration with signal systems and control panel indicators. MRServo-3 provides a single set of accessory contacts in addition to a set of PowerFrog contacts which intelligently route power to solid frog turnouts. PowerFrog eliminates the need for special current limiting circuitry or frog “juicers” in these situations.
Each kit comes complete with the control board, servo, hardware, throw wires, and a piece of heavy-duty mounting tape. Instructions are also provided in each kit and an installation tutorial can be found here.
As with all Iowa Scaled Engineering products, MRServo is guaranteed for life against manufacturing defects. And for you adventurous modelers, it is an open-source / open-hardware product. Full schematics, design files, and source code are available on the product documentation pages. We encourage you to build your own, improve upon it and, if you so choose, submit your ideas back to us so everyone can benefit.
Available exclusively on the MRServo-3, PowerFrog technology provides a reliable, short-proof way to route power to solid frog turnouts. (Examples: handlaid, Peco Electrofrog™, Shinohara™, and Walthers™ models.) These turnouts will create a short if the points make contact with the opposing rail before the contacts driving the frog switch polarity. Traditionally, the solutions have included additional gaps in the point rails to isolate the frog, various current limiting devices, or active frog “juicers”. With PowerFrog, this is no longer necessary. When MRServo starts to throw the points, it momentarily isolates the frog. Once the servo completes throwing the points, it sets the direction relay to the correct polarity and, after a small delay, re-energizes the frog.
Putting this intelligence in the switch machine has many benefits. First of all, it works with any control system: DCC (any make), pre-DCC command control, traditional DC, 3-rail, etc. Secondly, since the switch machine already knows the position of the turnout, you no longer have to create an intentional short-circuit to signal the frog “juicer” to change the polarity. Third, the overall cost can be significantly less. So, protect your wallet and your investment in turnouts and use MRServo as your switch machine of choice!
Installation of MRServo is straightforward, but please be sure to follow the directions. After you have installed a few, the process goes very quickly. A tutorial on our recommended installation procedure can be found here.
As mentioned above, MRServo is ideal for space-constrained applications such as multi-deck layouts. Both the control board and the servo itself are small, resulting in a very low-profile installation.