C14

Proximity Sensor

Abstract: 4 channel real-time proximity sensor controller.

Specs

Similar to the C33, this module provides I2C interfaces for four P16 proximity sensors (VCNL4040) to monitor track occupancy. In addition, an EDG bus bridge is included for accessory connections.

Features,

  • HDX interface (2Mb, half duplex, RS-485 differential)
  • 4x I2C bus for proximity sensors
    • true real-time sensor reporting over the HDX bus
    • software configurable detection range [0.5cm-20cm]
  • 1x EDG bridge with
    • up to 1000mA (using a step-down converter)
  • firmware update over the bus

Each sensor is connected via a dedicated I2C bus to minimize electrical interference. However, the individual I2C bus segments should be kept as short as possible. Each bus segment should be a maximum of 100 cm long. 50 cm has proven to be a very robust setup.

For current and Railcom sensing please refer to C13.

Examples

Up to 4 proximity sensors can be connected to the C14 module. Within the management system, the sensors appear as normal track occupancy feedbacks. Signaling occurs in real time with a guaranteed response time, allowing sensors to be used for time-critical loco control.

The example shows proximity sensors used as STOP sensors in a marshalling yard to ensure the detection of rail vehicles regardless of whether they are drawing power or not.

C13 and C14 sensors can be mixed as desired in the layout.

CLI interface

The sensor data appears as occupancy sensors, but reporting the object distance detected, as opposed to track current with the C13. The reported distance is in ‘ticks’ and has no unit. The higher the tick, the closer the object.

O:\rtb>rtbclient --proximity -v
Cnt   Proximity IF                  Detect  Heartbeat  T[C]   Edge[A]  Ch-3  Ch-2  Ch-1  Ch-0  Occ
  1 * 000dc140-506c972d73b0414a   12:58:50   14:12:15    18     0.000     0     0     2     2  00000011
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