REV2 Universal DC/DCC Model Railway Autoreverser with Points Control

About the Product

Key Features

• Automatic track polarity switching for reversing loops and complex track arrangements
• Compatible with conventional DC, DCC and Hornby™ HM7000 systems
• Infra-red train detection switches polarity before the train reaches the conflicting section
• Automatic control of compatible solenoid point motors
• Suitable for single loops, double loops and central reversing sections
• Supports automatic train routing without manual switching
• Different wiring configurations available for DC, DCC and HM7000 layouts
• Two supplied infra-red sensors for automatic train detection
• Additional sensors can be used for bi-directional central reversing sections
• Sensor detection range up to approximately 25mm
• Optional external LEDs can indicate normal and reverse point states
• Optional push-button inputs for manual point operation
• Five-second sensor clearing period helps prevent repeated point switching while a train passes
• Remembers the previous point and polarity state when powered back on
• Reverse-polarity protected power input
• Suitable for a wide range of model railway scales including TT120, OO and HO
  

DC, DCC & Hornby™ HM7000 Compatibility

One of the main advantages of the REV2 is its ability to operate with several different model railway control systems.

Conventional DC

On a traditional DC layout, the REV2 maintains the appropriate track polarity for the direction in which the locomotive is travelling. When a train approaches a section with opposing polarity, the REV2 detects it using the infra-red sensors and corrects the track polarity ahead of the locomotive.

DCC

On DCC layouts, the REV2 can switch the track feeds as required without affecting normal decoder operation. DCC locomotive decoders adapt to the changed track feed, allowing the polarity to be switched while locomotives are operating.

Hornby™ HM7000

The REV2 is compatible with HM7000 locomotives operating with either a DCC track supply or a 15V DC track supply and Bluetooth/App control.

The exact wiring arrangement required depends on the type of track power being used.

Automatic Points & Polarity Control

In addition to changing track polarity, the REV2 can automatically operate a solenoid point motor.

When a train is detected by Sensor 1, the module operates the points to the NORM position and sets the corresponding track polarity. When Sensor 2 detects a train, the points are operated to the REV position and the track feed is switched to reverse polarity.

This allows the points and track polarity to be coordinated automatically, making it possible for a train to travel around a reversing loop and rejoin the main line without the operator manually changing either the points or track polarity.

Typical Layout Applications

The REV2 supports several different reversing arrangements, with the appropriate wiring depending on the layout and whether DC, DCC or Hornby™ HM7000 track power is being used.

Single Reversing Loop

A single reversing loop can be completely automated using the REV2. Infra-red sensors detect the train as it travels around the loop, allowing the module to automatically set both the points and the required track polarity.

In the primary wiring arrangement, the track outside the loop has its polarity controlled by the REV2. This configuration can be used with DC, DCC and Hornby™ HM7000 layouts.

This arrangement allows the REV2 to automatically operate the points and control track polarity as the train enters and leaves the reversing loop.

For DCC and HM7000 layouts, an alternative arrangement is also available where the polarity of the loop itself is changed rather than the main layout. This alternative is not suitable for conventional DC locomotives.

Double Reversing Loops

The REV2 can also automate layouts with a reversing loop at each end.

One sensor is positioned on each loop and the locomotives travel around the loops in a predetermined direction. The direction can be altered by changing the point motor wiring and repositioning the sensors.

The primary arrangement controls the polarity outside the loops and is suitable for DC, DCC and Hornby™ HM7000. An alternative configuration for non-DC layouts can instead switch the polarity of the loops themselves.

Central Reversing Section - Bi-Directional

The REV2 can control a central reversing section on DCC and Hornby™ HM7000 layouts, allowing trains to travel through the reversing section in either direction.

Additional sensors ensure that a train approaching either end of the reversing section is detected before reaching a track gap. The REV2 then automatically changes the track polarity as required so the train can continue without creating a polarity conflict.

The section between the two central sensors must be longer than the longest train that will use the layout. Additional sensors are required for this bi-directional arrangement.

Additional Layout Wiring Diagrams

The REV2 instruction manual also includes wiring diagrams for alternative single-loop and double-loop configurations, as well as a unidirectional central reversing section.

Infra-Red Train Detection

The REV2 uses compact infra-red sensors containing both an emitter and detector. The sensor reflects infra-red light from passing rolling stock, allowing the module to detect the train without requiring mechanical switches or additional electrical connections to the rails.

The sensors are normally installed beneath the track bed but can also be mounted alongside the track. Detection range is up to approximately 25mm from the face of the sensor.

After a train is detected, another detection is prevented until the sensor has been clear for five seconds. This helps prevent repeated points operation while the remainder of the same train is still passing over the sensor.

Sensor Wiring

Correct sensor connection is important for reliable operation of the REV2.

Sensor 1 connects to terminals A1, C1 and G1, while Sensor 2 connects to A2, C2 and G2. The sensor wires can be extended where required using suitable small-gauge cable.

This diagram identifies the emitter and detector connections and the correct orientation of the supplied infra-red sensors.

Sensor Installation

The infra-red sensors are normally installed below the track bed so that they detect reflected infra-red light from passing locomotives and rolling stock.

They can be mounted through an approximately 8mm hole in the baseboard. Alternatively, the sensors can be positioned alongside the track where this is more convenient.

The maximum detection range is approximately 25mm from the face of the sensor.

Optional Push Buttons & External LEDs

External LEDs can be connected to the LED1 and LED2 terminals to provide additional indication of the point setting.

LED1 indicates the NORM points output, while LED2 indicates the REV points output. The LEDs remain illuminated between point operations.

Optional push buttons can also be connected to PB1 and PB2. Pressing PB1 operates the NORM points output, while PB2 operates the REV points output.

This provides a convenient way to manually operate the points when required while retaining the REV2's automatic functionality.

Power Supply Requirements

• Power Supply: Regulated 12V DC
• HM7000 Supply Option: 15V DC HM7000 track supply when applicable
• Recommended Power Supply Rating: 1A to 2A
• Module Current Consumption: Approximately 0.5A
• Power Input Protection: Reverse-polarity protected
• Train Controller Accessory Outputs: Do not use unsuitable accessory outputs

When using Hornby™ HM7000 with a 15V DC track supply, the same 15V DC supply can also be used to power the REV2.

A separate regulated supply is recommended for other installations. Auxiliary accessory outputs from conventional train controllers may be insufficiently regulated and could result in unreliable operation or damage.

Documentation & Support

For complete installation instructions, all supported layout wiring arrangements, sensor connections, setup information and troubleshooting guidance, please download the latest REV2 instruction manual:

Product Instruction Manual