Signalogic Systems


Elegant Switch Control for any Model Railroader


Whether you are a casual model railroader or an intense operations driven model railroader, a common thread to all model railroaders is switch control.  Whether this requirement comes from the need to control hard to reach switches or the desire to have a dispatcher route trains across your empire, switch control is required.

Signalogic Systems provides a unified solution for switch control needs of all model railroaders.  These solutions are designed with the purpose of providing a starting point for signal system interfaces, but can be used as a stand-alone product, only requiring 12VDC.

Although actual switch machine technology differs, modellers should not need to worry about different controls for each of these devices.  Signalogic Systems provides simple to use solutions with the following functionality:

Twin Coil Solenoid Control

TCSC: Twin Coil Switch Controller.

TCSC Twin Coil Switch Controller

Twin-coil switch machines have been around for more many years.  They are a reliable means of moving switch points electrically.  The TCSC controller combines the power of capacitor discharge circuitry to ensure proper throwing forces to the switch by discharging an amplified voltage from a nominal 12VDC input.  Without any additional switch contacts, the TCSC can determine the position of the switch, even if moved by hand!!  This removes any uncertainty about whether a switch is in the position expected. 

The following features are included:

TCSC Installation and User Manual

Circuitron Tortoise Switch Control

TSMSC: Tortoise Slow Motion Switch Controller.

TCSC Twin Coil Switch Controller
TCSC Twin Coil Switch Controller

The Circuitron Tortoise provides realistic motion of switch points similar to a power switch machine. Contacts on the Tortoise can be used to indicate position of the Tortoise for panel lights, signalling and frog power routing, however, these contacts are not prototypical for signal purposes.  The TSMSC provides positive indication of the switch position once the Tortoise has achieved its final position. 

The following features are included:


Simplified Crossover Operation

Two  TCSCs and two TSMSCs or one of each can be paired together to control crossover switch pairs with one control and indication line.

TSMSC Installation and User Manual

Fascia Mountable Control Panel

SCP: Switch Control Panel 
TCSC Twin Coil Switch Controller
TCSC Twin Coil Switch Controller
TCSC Twin Coil Switch Controller

The SCP is designed to provide an elegant control interface to the TCSC and TSMSC boards.  A single low-profile button key is provided to throw a switch or crossover to the opposite position.  LEDs indicate the current position of the switch.

SCP Installation and User Manual


What do they do?.  Switches, or turnouts, provide a means of allowing trains to travel onto different tracks.  In many locations, particularly on mainline, switches can be moved remoted by 'switch machines'.  Different technologies exist to allow this to happen.

Switch Machines

Power Switch Machines.
Most typically used in CTC and other electrically controlled interlockings, switch machines provide a number of functions to ensure the safe movement of trains.  Switch machines are responsible for moving switch points to the position required to route a train, but in addition, the switch machine must also provide adequate mechanical locking to ensure the points are held in place with the enormous forces of a train.  The switch machine must also continuously monitor to ensure that the switch points are actually positioned within the required tolerance to allow a train to pass.

Power-only Switch Machines.
This type of switch machine can only be moved by a signalman or interlocking controller (dispatcher in CTC).

Dual Control Switch Machines.
This type of switch machine is similar to a power-only type machine but can also  be placed in a hand operation mode.  This mode allows a crewman to operate the switch points with a long handle lever.  Once operated, the mechanical locking force on the switch points is diminished until the machine is operated by power once again.  A switch machine will report the switch in neither position to a signal system once operated in hand control, thus making valid permissive signal aspects impossible over the switch.  The signal system will not receive an indication of position until the machine is operated successfully by power to ensure full mechanical locking forces are present.

Switch Control

About Switches

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