Electrical control and protection board for RealTrax turnouts
This module provides an interface between a MTH AIU/relay panel and RealTrax turnout solenoids. My entire control system is built up from various "modules" that are wired together using custom cable assemblies. All wiring is color coded. The system is a "plug and play" design.
This combination turnout (switch) control and protection board is designed for use with MTH RealTrax remote controlled turnouts. The MTH switch solenoids require a minimum of 10 volts at 1.25 amperes to activate remotely. These solenoids are activated by individual heavy duty relays.
An individual 18 V AUX turnout power circuit is used. Track voltage is NOT used. To protect against a short circuit I have installed limiting resistors and individual fuses for each of these control circuits.
The overall schematic for the turnout control system is attached.
In the event of a single failure (short) the current to each solenoid is limited to no more that 1.75 amperes per solenoid or 4 amperes maximum due to fuse protection. Any fault will not affect any other circuit. The turnout control and protection board (shown) is used with an 8 channel fuse box (shown). An individual 18 V AUX power circuit is used.
