Rail mounted sensors
Rail mounted sensors
This is one for Alex I suspect.
Recently spotted at pilning and Bathampton small flat square items bolted to inside of one rail, usual a pair side by side with wire running off to the trunking. I guess some kind of new axle / train sensor. The one at Bathampton is only connected to a drum of cable.
Secondly, why is there every so often a length of cable running in center of sleepers for a fair length which then finnishes and re-appears again a way along track. Does it pick up head code from transponder and sent to signal panel to show which train is where.
Recently spotted at pilning and Bathampton small flat square items bolted to inside of one rail, usual a pair side by side with wire running off to the trunking. I guess some kind of new axle / train sensor. The one at Bathampton is only connected to a drum of cable.
Secondly, why is there every so often a length of cable running in center of sleepers for a fair length which then finnishes and re-appears again a way along track. Does it pick up head code from transponder and sent to signal panel to show which train is where.
- stumpytrain
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Re: Rail mounted sensors
Hi,nickt wrote:This is one for Alex I suspect.
Recently spotted at pilning and Bathampton small flat square items bolted to inside of one rail, usual a pair side by side with wire running off to the trunking. I guess some kind of new axle / train sensor. The one at Bathampton is only connected to a drum of cable.
Secondly, why is there every so often a length of cable running in center of sleepers for a fair length which then finnishes and re-appears again a way along track. Does it pick up head code from transponder and sent to signal panel to show which train is where.
Sorry, I haven't been paying enough attention to this forum recently!
There's a Hot Axle Box Detector in the Pilning area on the Up Tunnel, that could be what you've seen in the Pilning area. However, there isn't one of these at Bathampton. Could you provide a photograph? I might be able to tell then!
The length of cable running down the centre of the 4' sounds like an ATP infill loop. You can probably find more information elsewhere on the internet but basically it updates the train's ATP before he gets to the signal allowing the driver to power up sooner.
Alex
- Rich_Eason
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Re: Rail mounted sensors
"I think" I have seen a treadle on the up line next to the exit of the loop, perhaps this is what you have seen?stumpytrain wrote: There's a Hot Axle Box Detector in the Pilning area on the Up Tunnel, that could be what you've seen in the Pilning area. However, there isn't one of these at Bathampton. Could you provide a photograph? I might be able to tell then!
These are grey boxes typically 6x6inches with a wire poking posistioned so that the wheel flange depresses the paddle.
Perhaps used for clearing the signal at the end of the up loop?
- Rich_Eason
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Re: Rail mounted sensors
"I think" I have seen a treadle on the up line next to the exit of the loop, perhaps this is what you have seen?stumpytrain wrote: There's a Hot Axle Box Detector in the Pilning area on the Up Tunnel, that could be what you've seen in the Pilning area. However, there isn't one of these at Bathampton. Could you provide a photograph? I might be able to tell then!
Blown up from a much larger image

These are grey boxes typically 6x6inches with a wire paddle poking out positioned so that the wheel flange depresses the paddle.
Perhaps used for clearing the signal at the end of the up loop?