Signals at West Buckland Railway

Signals for West Buckland Miniature Railway

The purpose of the signalling system is to promote safer running of the railway.

To that end we have devised and agreed 'The Moving Parts Rule'

There are a number of 'Moving Parts' on the railway of concern to the Signalling System.

The signalling system needs to 'know', with certainty, the physical positions of items including semaphore signals, track turnout parts, level crossing gates, traversers, and maybe other items.

The MOVING PARTS RULE

"An assembly including any 'Moving Part' is to include a pair of position sensors, each with a single electrical logic switch output. This pair of electrical signals (a 2 bit binary code) provides sufficient information for the signalling system to read the status of the moving part as being in one of four possible states : -

In safe position 'A'

In safe position 'B'

Not in safe Position 'A' and not in safe Position 'B'

Faulty or missing"

This minimal interface will be sufficient to return unambiguous confirmation of position of single moving parts such as a gate, a semaphore signal etc.

Where mechanical locks or interlocks are used, these are in themselves separate 'moving parts' which will need to comply with the Moving Part Rule.