Truro East x-over T33

This only happens in 2000 era as T33A&B are not locked normal in 2009 & 2016 eras

I wonder if that's a bug then?

It's a standard principle of Western locking that the route must be set to the second signal and therefore that any points beyond a signal will not just lock the signal immediately protecting them but the signal before that. This enforces the general Rule Book requirement for mechanical signalling not to allow a movement up to the signal immediately protecting a conflicting movement. I would honestly be very surprised if that bit of mechanical locking was ever removed. 33 ought to lock 4 and vice versa. But once 4 goes back there's no reason for 33 to remain locked.

You could put the body of the freighter in platform 2 and run the loco round through platform 3 as the route approaching T28 does not lock T33A&B?

TUT in post 161017 said:

It's a standard principle of Western locking that the route must be set to the second signal and therefore that any points beyond a signal will not just lock the signal immediately protecting them but the signal before that. This enforces the general Rule Book requirement for mechanical signalling not to allow a movement up to the signal immediately protecting a conflicting movement. I would honestly be very surprised if that bit of mechanical locking was ever removed. 33 ought to lock 4 and vice versa. But once 4 goes back there's no reason for 33 to remain locked.

Ah now that's the interesting thing, u say MECHANICAL interlocking but given that T33 stays locked even after T4 has been returned to the frame providing that the TC on the UP line has then become occupied. It would indicate this is not a mechanical lock, rather an electric lock. Hence why I specified the Electric locking chart/conditions for that particular set of points.

rfw in post 161016 said:

You could put the body of the freighter in platform 2 and run the loco round through platform 3 as the route approaching T28 does not lock T33A&B?

I think I may have to! Would be interesting to see if this is a 'works as intended' issue though.

rfw in post 161016 said:

You could put the body of the freighter in platform 2 and run the loco round through platform 3 as the route approaching T28 does not lock T33A&B?

I think I may have to! Would be interesting to see if this is a 'works as intended' issue though.

Could you drop us a screenshot or a save please?

Robyn in post 161018 said:

TUT in post 161017 said:

It's a standard principle of Western locking that the route must be set to the second signal and therefore that any points beyond a signal will not just lock the signal immediately protecting them but the signal before that. This enforces the general Rule Book requirement for mechanical signalling not to allow a movement up to the signal immediately protecting a conflicting movement. I would honestly be very surprised if that bit of mechanical locking was ever removed. 33 ought to lock 4 and vice versa. But once 4 goes back there's no reason for 33 to remain locked.

Ah now that's the interesting thing, u say MECHANICAL interlocking but given that T33 stays locked even after T4 has been returned to the frame providing that the TC on the UP line has then become occupied. It would indicate this is not a mechanical lock, rather an electric lock. Hence why I specified the Electric locking chart/conditions for that particular set of points.

rfw in post 161016 said:

You could put the body of the freighter in platform 2 and run the loco round through platform 3 as the route approaching T28 does not lock T33A&B?

I think I may have to! Would be interesting to see if this is a 'works as intended' issue though.

Quite right, you did, I was responding more to rfw's suggestion that such a lock could have been removed. If it was removed I would be genuinely fascinated to know why.

33 points did have a plunger so they were electrically locked, presumably to provide track locking in the absence of an FPL (which would normally be the lever that would be electrically locked) but the apparent electric locking in the sim holding 33s normal with a train standing at 6 seems, indeed, as you rightly say to be an error, I can imagine no need for that at all. It is possible that when they did make the alterations to that box some sort of timeout was added, but it seems really unnecessary on a set of mechanical points right outside the box which provide a simple mains crossover and aren't fit for passenger moves. But let's say it was provided. Some weird things are provided when a modern mind is invited to start mucking around in a signal box. But it shouldn't never time out.