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hen utilised to monitor a HXP-3 track circuit, the condition monitoring data-feed between the HXP-3 rack and the in-situ monitoring PC is intercepted. If an existing S-LX device is in-situ monitoring the VHLC crossing, then both S-LX devices may share a power supply, and the HXP-3 S-LX device does not require a modem. It can be networked to the VHLC S-LX device.
What data is available?
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Receive level, and received phase is available as a real-time data stream for both tracks. The "Ring Status" is a series of (undocumented) bits which can be seen to change as the predictor changes state. It should be possible to label these by comparing the VHLC data and the predictor data.
Real-world sample data can be seen on the graph below.
- The data is known to be untidy (the glitchy section shortly before the track clears) at the point where the train is "on-top-of" the predictor.
- The vertical section in the trace during clearance is due to the line section being artificially shorted with a block joint (upper track, see blue ring in diagram). Track diagram:
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