DAP1-NS Infra-Red Model Railway Semaphore Signal Controller

About the Product

The BLOCKsignalling DAP1-NS is an automatic model railway semaphore signal controller with built-in infra-red train detection, designed specifically to automate compatible Dapol semaphore signals. When a train passes over the sensor, the module automatically operates the signal without requiring track switches or modifications to the rolling stock.

The built-in sensor projects invisible infra-red light upwards towards the underside of passing rolling stock and detects the reflected light. The sensor is installed beneath the track through an 8mm hole and requires only around a 2mm gap between the sleepers, making it suitable for N gauge and larger scales.

The DAP1-NS connects directly to the signal's four wires. It shares the signal's power supply and automatically replaces the manual switching action normally performed by briefly connecting the two yellow signal wires.

The module works straight out of the packet with no programming required. Train-clear time, the final delay before the signal returns to its original position and sensor sensitivity can all be adjusted if required.

Key Features

• Automatically operates compatible Dapol semaphore signals.
• Built-in infra-red train detection.
• No modifications to locomotives or rolling stock required.
• Sensor mounts beneath the track through an 8mm hole.
• Suitable for N gauge and larger model railway layouts.
• Only four signal wires to connect.
• No programming required for normal operation.
• Adjustable train-clear time.
• Adjustable delay before the signal returns to its original position.
• Adjustable infra-red detection sensitivity.
• Remembers the signal position when power is switched off.
• Operates from the same power supply as the semaphore signal.
• Compatible with 9–12V DC or 12–16V AC supplies.
  

Infra-Red Train Detection & Installation

The sensor is installed through an 8mm hole between the sleepers. As a train passes overhead, reflected infra-red light triggers the module and causes the semaphore signal to operate automatically.

Automatic Semaphore Operation

In its default mode, the semaphore signal normally remains at Danger. When an approaching train crosses the sensor, the DAP1-NS changes the signal to Clear. Once the complete train has passed and the programmed delay has expired, the signal automatically returns to Danger.

Gaps between individual carriages are ignored using an adjustable train-clear timer. The default train-clear time is 4 seconds, while the default final delay before returning the signal is 5 seconds. Both can be changed if required.

Dapol Semaphore Signal Connection

The DAP1-NS has four terminals:

• GND: AC supply connection or negative connection when using DC.
• ACIN/V+: AC supply connection or positive connection when using DC.
• SW1: Connects to one of the signal's yellow wires.
• SW2: Connects to the other yellow signal wire.

The two yellow wires can be connected to SW1 and SW2 either way around.

Adjustable Settings

Although no programming is required for normal operation, the DAP1-NS allows several settings to be customised to suit the layout.

The train-clear time can be adjusted from 1 to 255 seconds, while the final delay before returning the signal can also be changed. Infra-red sensitivity is factory set to 5 and can be adjusted from 1 to 10.  

Electrical Requirements

• Supply voltage: 9–12V DC or 12–16V AC.
• Recommended supply: 12V DC.
• Signal compatibility: Compatible Dapol semaphore signals.
• Train detection: Built-in infra-red reflection sensor.
• Installation hole: 8mm.
• Minimum sensor gap between sleepers: Approximately 2mm.
• Signal connections: Four wires.

A 12V DC supply is preferred when available. When using DC with the Dapol signal, the positive supply should connect to the signal's red wire for its lamp to illuminate correctly.

Documentation & Support

For full installation instructions, signal wiring, programming, sensitivity adjustment and troubleshooting, please refer to the product instruction manual:

Product Instruction Manual