Locking problem

AN53 (Liverpool South Parkway down fast starter) locks points 48 both ways. This doesn't seem right and causes delays when a down train from Hut's Cross crosses an up train for Weaver Junction.

The problem existed in the pre-loader V5 version.

Thanks everybody. I should have done more research to see whether Allerton was still a mechanical box.

A note in the manual would be nice.

It may be the Route Holding principle from the old Allerton Junction mechanical interlocking? To quote an old BRB Training Manual on mechanical interlocking

"Levers operating stop signals next in advance of trailing points operated from the same box should, when operated, lock such point levers in either position, unless the locking will unduly interfere with traffic movements for which there is adequate space between the signals and the points concerned"

Hope this helps

A note in the manual would be nice.

CGP in post 128757 said:

It may be the Route Holding principle from the old Allerton Junction mechanical interlocking? To quote an old BRB Training Manual on mechanical interlocking

"Levers operating stop signals next in advance of trailing points operated from the same box should, when operated, lock such point levers in either position, unless the locking will unduly interfere with traffic movements for which there is adequate space between the signals and the points concerned"

Hope this helps

What was the logic behind this? The only benefit I can see is preventing a signaller moving the trailing points under a passing train- but in any case, the points in question are locked by a track circuit? It does seem to add a lot of operational headaches to a layout.

CGP in post 128757 said:

It may be the Route Holding principle from the old Allerton Junction mechanical interlocking? To quote an old BRB Training Manual on mechanical interlocking

"Levers operating stop signals next in advance of trailing points operated from the same box should, when operated, lock such point levers in either position, unless the locking will unduly interfere with traffic movements for which there is adequate space between the signals and the points concerned"

Hope this helps

What was the logic behind this? The only benefit I can see is preventing a signaller moving the trailing points under a passing train- but in any case, the points in question are locked by a track circuit? It does seem to add a lot of operational headaches to a layout.

Exeter west has the same arrangement with 52,53 and 54 points on the down goods which are locked by 122 (the down main section signal) as they aren't track circuited and the system therefore can't prove its safe to move them until 122 has been returned to danger.

As Stephen says, sometimes putting a train out to 122 at danger is the better option if an up train is approaching to prevent delaying it while a slow moving goods clears 122 which is a fair distance away from the box.

Exeter west has the same arrangement with 52,53 and 54 points on the down goods which are locked by 122 (the down main section signal) as they aren't track circuited and the system therefore can't prove its safe to move them until 122 has been returned to danger.

As Stephen says, sometimes putting a train out to 122 at danger is the better option if an up train is approaching to prevent delaying it while a slow moving goods clears 122 which is a fair distance away from the box.

jc92 in post 128868 said:

Exeter west has the same arrangement with 52,53 and 54 points on the down goods which are locked by 122 (the down main section signal) as they aren't track circuited and the system therefore can't prove its safe to move them until 122 has been returned to danger.

As Stephen says, sometimes putting a train out to 122 at danger is the better option if an up train is approaching to prevent delaying it while a slow moving goods clears 122 which is a fair distance away from the box.

This has been bugging me since I bought the Exeter West simulation as it blocks the up passenger lines. It seems ironic in that the down goods train passes directly in front of the box.

I did once find the technique Andrew G describes, but forgot to write it down.