Re: Unmanned Railway Crossings

["Notagunzel" <notagunzel@bigfoot.com>]

<sgpal@hotmail.com> wrote in message 86ul5n$sjj$1@nnrp1.deja.com">news:86ul5n$sjj$1@nnrp1.deja.com...

> Indian Railways have 26 000 unmanned level crossings, where the road
> buses and trucks have free access to cross the railway tracks, all the
> time.

Not dissimillar to Australia, where there are many rural level crossings
with passive protection.

> There are frequent ugly accidents at the level crossings as the
> road vehicle driver can not hear the whistle of the railway engine, due
> to the masking effect of road vehicle diesel engine.

What sort of Road rules are in force at passively proected crossings in
India?  To road users have to Stop?  US research (start looking at
www.fra.dot.gov) shows a reduction in accidents at passively protected Xings
with a Stop sign, as compared with a Yield or Give Way signs (where the Road
User doesn't have to stop). This is dependent of course on how well the Road
Rules are enfororced.

> It may be possible to equip each level crossing with :
> 1. Two solar panels, one on either side of the track, about 1 Sq m
> area; 2. Two Lead acide maintenance free batteries, fed directly by the
> Solar panels;
> 3. A switch to start a flashing light to warn the road users about the
> presence of a " Railway Crossing ", during the dusk hours;

First I'll describe the actively protected level crossings in Australia.
Apart from a handful of remaining Gated level crossings, which have their
origin with 19th century British practice, all actively protected level
crossings have either Flashing Red Lights, or for urban & busy rural
crossings, Boom Barriers operating in conjunction with Flashing Red Lights.
These generally operate automatically on the approach of a train, giving
20sec. warning for Flashing Lights, or 25 sec. for Boom Barriers.

Australian (which is based heavily on US) practice for Flashing Lights is to
have 1 control cabinet, near the Xing, this contains the control equipment &
the power supply (either a mains AC supply or Solar Panel float charging a
battery).  For simple crossings 2 flashing light masts are used diagnally
opposite, each mast has 2 lights in each direction, alternately flashing, so
the Road User sees 4 flashing lights, except when a train obscures 2 of
them.  (This drawing assumes left hand roads).  Busy & curved roads
sometimes need more masts.

      Track
      |   |
Mast o|   |
------|---|------
      |   |   Road
------|---|------
      |   |oMast
      |   |

Some method is needed to actually detect the train.  This can be a track
circuit, which uses the rails as an electrical circuit, when a train
approaches, it short circuits the track circuit, dropping a relay which
starts the flashing lights.  Well that's the simplified explanation.

Other more exitic ways of starting a level crossing can use axle counters or
predictors.

> Any suggestions to cut down the cost and to improve the reliability of
> the system are welcome.    Dinesh Bansal, Chennai, India

Reliability is the key factor.  Level Crossings in Australia are constructed
to fail safe, when they fail, the Lights/Booms will operate continually.
But the converse is important.  They should be reliable in service, so that
the Road User isn't always finding a defective set of Lights, otherwise this
will 'desensitize' the Road user as to the importance of the warning.  This
of course means active level crossings aren't cheap.  So as well as
targeting active protection to crossings with high road & rail vehicle
numbers, having good signage at passive crossings (with a Stop sign) is
important.

End of lecture. (Hope this didn't confuse you). |-)

--
Mr Notagunzel.
Rail Transportation Connoisseur
notagunzel@bigfoot.com
(Regrets to announce there will be no further moves at
http://www.geocities.com/nota_gunzel
until further notice is issued from this office)