
February 2011 in Network Rail and Suppliers
Level Crossings
Equipment
Scotland
A reporter is concerned that an audible alarm at Dunkeld signal box, which is for Murthly level crossing, has been out of action for more than six months. The crossing is on the Inverness Line north of Perth.
The alarm would normally alert the Signaller audibly that the automatic half barriers are not functioning correctly. For example, the barriers could 'fail safe' in the lowered position and then not return to the raised position. Frustrated motorists and pedestrians, who have been waiting for several minutes at the crossing, have been known to cross the Line by weaving through the half barriers when trains are approaching. The Line speed here is 80 mph. In the absence of an audible alarm, a temporary solution has been set up with a white light that is not illuminated if the barriers have failed after a train has passed over the crossing. The issue that the reporter highlights is that a Signaller must pay close attention to this light all the time whilst on duty. In contrast, the required audible alarm would immediately alert the Signaller's attention and help prevent an incident if the barriers failed.
Network Rail would like to thank the reporter for bringing their concerns to our attention.
Could Network Rail clarify when the audible alarm will be
fully functional again?
The barrier indication unit was damaged by a lightning storm.
These units are now obsolete with no identical spares available.
The unit was taken out of the signal box and sent to our technical
support team to see if they could repair it as they have done with
others in the past. Unfortunately after several weeks of trying,
sourcing various components as replacements with the ordering time
that it takes, the unit was declared un-repairable due to the
obsolescence of the remaining components, the best solution we
could offer at the time was the lamp driven from the existing
circuitry as the audible timer was generated from within the unit
itself and we had no way of recreating that. We have now looked at
the circuit diagrams and discussed these with the Level Crossings
Maintenance Support Engineer; an alternative solution has been
reached and arrangements have been made to get an audible alarm
reinstated by the 19 February 2011.
