Ground frame query

[Max Legroom]

Hi all

 

On my layout, Jamaica Road, I'm installing a ground frame to control the exit from the up platform road to some sidings. Here is a pic which hopefully makes things clear.

 

 

The sidings are off to the lower right and the nearest siding forms the head shunt. The ground frame will be near the foot crossing. Each of the two points will have a lever on the frame but my question is will either of the points need an additional lever to lock the points? The exit from the up platform road is via a trailing point.

 

Any advice much appreciated.

 

Max

[The Stationmaster]

Assuming normal directin running the ground frame will on;y needa single lever as the running line point is trailing for passenger train movements.  That single lever will work bothe the point in the running line and the point in the sidings which forms a crossover with teh running line point and acts as trap point for the sidings.

 

If the Up line is used by passenger trains  in both directions then it would additionally need a Facing Point Lock (FPL) which would need an additional lever - painted blue - in the ground frame.   But why use a ground frame for the siding connection - there is what appears to be a facing crossover immediately next to it in teh running lines which would nevitably be worked bya signal box of some sort or are you using modern signalling with remotely controlled points and colour light signals?   If the latter is the case then you might even need a third, red, lever in the gorund frame to slot a position light signal but that varied with Regional practice. 

[Max Legroom]

Hi Mike

 

Thank you for your help. The scenario is that the signal box has been demolished and the mainline is controlled remotely with colour light signals and point motors. The ground frame was installed just to control access to the sidings. So just one red lever should do the job based on  your advice. I guess the staff on the ground would need the key to unlock the frame and permission from the power box. This is a fascinating area that I've never bothered to look into before.

 

Best wishes

 

Max

[Titanius Anglesmith]

10 minutes ago, Max Legroom said:

The scenario is that the signal box has been demolished and the mainline is controlled remotely with colour light signals and point motors. The ground frame was installed just to control access to the sidings.

 

There's a similar situation at Upminster, where there's a ground frame giving access to sidings from the bay platform, despite Upminster IECC being literally a stone's throw away.

[The Stationmaster]

2 hours ago, Max Legroom said:

Hi Mike

 

Thank you for your help. The scenario is that the signal box has been demolished and the mainline is controlled remotely with colour light signals and point motors. The ground frame was installed just to control access to the sidings. So just one red lever should do the job based on  your advice. I guess the staff on the ground would need the key to unlock the frame and permission from the power box. This is a fascinating area that I've never bothered to look into before.

 

Best wishes

 

Max

Precisely what you need depends to some extent on the period and BR Region involved because different Regions did things in slightly different way.  The ground frame would be electrically released by the remote signal box usually via a j key release instrument which released teh key which would be used to unlock the lever frame itself.

 

The pictures below are na preserved line but use basically Western region equipment and show two different ways of doing the same thing in terms of position of the key release on teh ground frame as well as a key instrument..

 

 

Key re;ease on FPL lever

 

 

 

Key release in teh more common place at base of levers.

[russ p]

Southminster  is similar has a combined release lever / facing point lock , a black point lever and two red signal levers