Indian railways is using single section axle counters in absolute block for last vehicle check for which overall MTBF is less than 2000 hrs for most of the axle counter makes. We use preparatory reset for this application and hence first train in the block goes on manual authority and not on signals, this causes detentions to trains. I am looking at MTBF figures of axle counters in various countries and what measures have been taken to improve their reliability.

Thanks.

Akhilesh Yadav,
Director Signal,
RDSO Lucknow, India.
Link removed

After some early hiccoughs the UK axle counters are now starting to approach the reliability of the track circuits that they have replaced. In some areas they far exceed it. I can probably find you a contact in Network Rail who can give your more precise figures.

What are the main reasons for the failures of your axle counters?

Peter Sheppard
Ebeni Limited

-------------------------
Peter Sheppard
Chair IET Transport Sector
Member Transport Policy Panel

Thanks Peter,

It would be great if you can provide me a contact in NR who can give me reliability figures and, probably, also help us by telling about measures taken that have resulted in improved reliability.

Most cases of failures here are of "failed after a train, reset & restored" type. We are looking at many things like:
1. Communication media which may get disturbed by some transient we have not taken care of .
2. Power supply ripples causing malfunction
3. wheel profiles variations or other part of some locomotives disturbing axle counter
4. we also have many engineering push trollies which have to be rejected by axle counters. This is achieved by desensitizing the sensor for smaller and spoked wheels. This is not foolproof but works most of the time. This is also one of the causes of failures.

Thanks again for the help.

Akhilesh