Clearing Point Violation

Can someone explain what this is, and how I might avoid it? I have vaguely established that setting the points before setting the route at Hilton Jnc prevents this from occuring when I send a train to Ladybank - but I'm yet to workout how to avoid getting this when setting a route into the Montrose sidings - even when there's not a train in sight in either direction, I get a 'clearing point violation' - can someone explain? I've not been able to find anything in the manual or forums that really explains this.

Thanks

So in absolute block world the line is divided into sections, with a signal box at the start (signal box A) and a signal box at the end (signal box B). Signal box B will of course be at the start of the next section to signal box C and so on.

The section is the line between the last stop signal controlled from one signal box, and the home signal (the first stop signal) controlled by the next signal box.

In absolute block, signaller A offers the train to signal box B, by sending the appropriate is line clear?

Before signaller B can accept the train, they must make sure the line is clear up to and including the clearing point -- which is defined as the point up to which the line must be clear before a train can be accepted. If the distant signal is a colour light signal, the clearing point is usually 183m (200yd) beyond the home signal. If the distant is a semaphore, the clearing point is extended to a point usually 400m (440yd) beyond the home signal. They must also ensure that all points within the clearing point have been set for the safety of the approaching train, that no conflicting movement has been authorised that will cross or foul the line within the clearing point and that no train has been accepted from another direction that requires a portion of the same line within the clearing point for acceptance,

Once signaller B has accepted that train by acknowledging is line clear they cannot allow the line to be obstructed within the clearing point for that train until the train has been stopped at the home signal or has passed beyond any points or crossings that signaller B wishes to use within the clearing point. This applies unless signaller A sends cancelling (3-5) or the train has failed.

So

Before you the SimSig player send a train from one signal box to the next you have to make sure that the line is clear up to and including the clearing point (183m or 400m beyond the next signal, depending - exact locations can be found in the link hap posted) and that all the points within the clearing point are set for the safety of the train (so make sure a proper route is set all the way for a train, with no trailing points incorrectly set) and that you haven't signalled a train from another direction which also requires a part of the same line to be clear.

And then you cannot obstruct the clearing point and you must maintain a complete 183m/400m portion of line with all points within it correctly set until the train comes to a stand at the next signal. At Montrose, if you set the route into the sidings, you've destroyed the clearing point for the train.

And then you cannot obstruct the clearing point and you must maintain a complete 183m/400m portion of line with all points within it correctly set until the train comes to a stand at the next signal. At Montrose, if you set the route into the sidings, you've destroyed the clearing point for the train.

TUT in post 118118 said:

And then you cannot obstruct the clearing point and you must maintain a complete 183m/400m portion of line with all points within it correctly set until the train comes to a stand at the next signal. At Montrose, if you set the route into the sidings, you've destroyed the clearing point for the train.

Thankyou - that's very clear, (I think!) - so - is it even possible to route a train through to Montrose head-shut siding without causing this 'error'? I've ensured that the track is all clear in both directions, that that the points are set into the sidings and waited for the train to come to a halt at MS15 before setting the route, and the train proceeds, but as soon as it leaves the track section directly behind MS15, I get a violation penalty.

An excellent explanation, and may well reflect current practice. But back in the day the different companies (and their successor regions) varied in whether they allowed clearing points to be changed after accepting a train and before it came to a stand. The GWR was very strict in that regard; once you accepted something you were locked up until it stopped or passed, unless there was a specific exception in the Signal Box Special Instructions (AKA 'footnotes'). I have a feeling that way of working tended to be used where 4-track lines were paired by direction (such as the GNR), and certainly I've heard of an inspector who was ex-GN challenging a Midland line signalman who swung a junction with a train on the block (in fact, at Finchley Road, the train was almost certainly in the section). It would make sense that where lines are paired by use (such as the Midland or the LNWR), it would be considered aceptable to swing the clearing point - provided the new clearing point was properly unobstructed etc. There was even a provision in the General Appendix, of all places, that if points were to be swung ahead of an approaching train, the signalman must satisfy himself that it was safe to do so, having regard to the position and speed of the approaching train.

In other words you cannot have the points set for the siding when you signal the train up to MS15. You have to wait for the train to come to a stand at MS15 before setting the route into the siding (including moving the points). That should then work.

...In other words you cannot have the points set for the siding when you signal the train up to MS15. You have to wait for the train to come to a stand at MS15 before setting the route into the siding (including moving the points). That should then work.

TUT in post 118227 said:

...In other words you cannot have the points set for the siding when you signal the train up to MS15. You have to wait for the train to come to a stand at MS15 before setting the route into the siding (including moving the points). That should then work.

Ah - then something is definitely up - my train is stopped at MS15. The violation only happens after I've set the points and the train has passed MS15 into the siding.

Thanks for the background - very enlightening!

Dave

kbarber in post 118129 said:

An excellent explanation, and may well reflect current practice. But back in the day the different companies (and their successor regions) varied in whether they allowed clearing points to be changed after accepting a train and before it came to a stand. The GWR was very strict in that regard; once you accepted something you were locked up until it stopped or passed, unless there was a specific exception in the Signal Box Special Instructions (AKA 'footnotes'). I have a feeling that way of working tended to be used where 4-track lines were paired by direction (such as the GNR), and certainly I've heard of an inspector who was ex-GN challenging a Midland line signalman who swung a junction with a train on the block (in fact, at Finchley Road, the train was almost certainly in the section). It would make sense that where lines are paired by use (such as the Midland or the LNWR), it would be considered aceptable to swing the clearing point - provided the new clearing point was properly unobstructed etc. There was even a provision in the General Appendix, of all places, that if points were to be swung ahead of an approaching train, the signalman must satisfy himself that it was safe to do so, having regard to the position and speed of the approaching train.

Really interesting, thank you!

I looked through the rule book, but to be honest, I couldn't find anything explicit about changing the clearing points. It probably is still down to local instructions I would have thought? The rule book doesn't seem (as far as I could find) to explicitly address changing the clearing point from one acceptable clearing point to another acceptable clearing point. But, whatever the weather, a clearing point must be maintained, whether or not it's the same one throughout. And at Montrose, for example, the points can't be set into the sidings when the train is accepted or on the line.

Seems odd, also if the first route you set in a new sim is MS15 to US12, this is not a CPV.
After getting CPV for US5 to MS30, then MS15 to US12 is a CPV.

Can confirm I just had those violations too in a multiplayer game, looks like a recently introduced bug (maybe with the last sim update?) as there would've been mention of them further up in the thread if this bug had existed when NEScot came out.

Peter, please can you confirm if CPVs should only occur when the 'mechanical' option is ticked?