Signal areas controlled by NX panels

[Annetts key]

Based of locations I formerly worked the scope of the LCP was limited. Whilst in 'normal' operating mode they had control of signals protecting level crossings, the routes could be overridden by the respective controlling PSB.

However, when 'local control' was taken, it gave the signaller at that location control of loops and crossovers, without any intervention by the controlling PSB, though you then signalled trains at their direction. The usual instruction, when switched-in, was to work straight up and down unless advised. Each location was eexpected to take 'local control' for an hour or so each Saturday, for knowledge retention. You could be asked to switch-in at other times too.

For the LCP or 'emergency ' local panels that were on the area where I worked, the actual facilities varied, depending on the design. The rest of this post describes the two that I knew about. Both now removed.

Normal operation was that the main PSB controlled everything, the only thing that worked on the local panel was the indications and the on/off switch for the indications.

When in local mode, the main PSB had no control over any of the signalling controlled by the local panel. But the main PSB would continue to have valid indications if the remote control system (TDM) was operational.

On these local panels, only minimal circuitry was provided to try to avoid conflicting routes from being set. Unlike the far more complex circuitry at the main PSB which was designed to prevent stupid mistakes. So the signaller operating the local panel had to be more careful. The interlocking in any case would not allow a signal to show a proceed aspect unless it was safe.

On one emergency panel (W-s-M), a telephone concentrator and handset was provided so that all the SPTs and other lineside direct phones could be switched over.

One of these was at Weston-super-Mare, the other was at Filton Abbey Wood.

The W-s-M panel actually took control from the mechanical signal boxes in the area that were being replaced, before Bristol PSB A panel was ready. Only at a later stage of the resignalling did the PSB take control (I think it was only a couple of weeks).

 

[MarkyT]

If my dates are correct, that’s when panel 7 extended its control down the Arun Valley line to fringe with Arundel Signalbox. Although in recent history panel 5 has had it’s FDM equipment replaced between Keymer Junction and Preston Park and new Bi-directional signalling between Copyhold Junction and Balcombe tunnel junction, although I forget the exact dates now.

ISTR panel 7 was provided new in 2005 for Horsham resignalling. I assume it was built long enough from the start to accommodate the subsequent Arun Valley extension.

 

[Sunset route]

ISTR panel 7 was provided new in 2005 for Horsham resignalling. I assume it was built long enough from the start to accommodate the subsequent Arun Valley extension.

Not so, the original panel has been extended in length and modified quite a few times since it was installed.

 

[Krokodil]

Didn't Filton Abbey Wood have some kind of temporary panel during the latest resignalling?

 

[Annetts key]

Didn't Filton Abbey Wood have some kind of temporary panel during the latest resignalling?

The history of the area:
1970s - Bristol PSB took control of Filton Junction, Filton West and Patchway. Each junction area had its own interlocking, each in a red brick relay room building.

The interlocking at Filton Junction contained the TDM (Time-division multiplex) remote control system for the other two interlockings. None were provided with any local panels. Instead Filton Junction had a full selective override system and Patchway had a limited selective override system. No emergency facilities were provided for Filton West.

When Filton Abbey Wood station had a new additional platform line added, signalling alterations were required. Rather than modify Filton Junction Interlocking, a brand new route relay interlocking was provided next to Filton Abbey Wood station.

This replaced the interlocking for the Filton Junction area. But not the non-safely PO (Post Office) type relays for the Patchway and Filton West areas that were in the same relay room or the TDM.

The new Filton Abbey Wood interlocking had its own new TDM system and now controlled the Filton Abbey Wood and Filton Junction areas. It's this interlocking that had a local panel inside the REB that contained both the local panel and the new interlocking.

On this web site (Signalling Photos - The Railway Signalling Photo Archive) there is a photo showing the Filton Abbey Wood part of the Stoke Gifford / Bristol North / D position panel in Bristol PSB, this photo having been taken in 2007 some time after the new interlocking was commissioned - link to page with photo (can't copy the photo here due to the web site's restrictions). And a later, but clearer photo here.

Now, I can't remember if it was during these signalling works, or during the earlier works around Stoke Gifford / Bristol Parkway (in connection with the then new Royal Mail terminal) but because extensive alterations were required to the Stoke Gifford / Bristol North / D position panel in Bristol PSB, a temporary panel was provided in Bristol PSB. Once the alterations were complete, the temporary panel was removed.

Later on, when TVSC took control of the area, all the existing relay based interlockings were decommissioned, including Filton Abbey Wood and it's local panel. The panel had already been taken out of use due to an operational decision.

During the various stages as TVSC gradually took control, there were various temporary alterations to the panels in Bristol PSB. But no temporary panels anywhere in the PSB or in any Interlocking controlled by the PSB.

 

[Port Road]

I wondered about it, but it’s an OCS (One Control Switch) as opposed to an NX.

Right enough it's not NX at all (It was OCS until the 90's but I think it's actually 2 seperate 'turn & push' type panels now).

 

[Annetts key]

There's some photos of Weston-super-Mare emergency panel also at the same web site that I linked to above, click here. Again, due to restrictions, I can't copy them here.