South Wales 'Metro' updates

[MikePJ]

It appears that the December timetable has been loaded up for the Treherbert line.

It is shown with 4tph Mon-Sat (2tph to Cardiff Bay, 2tph terminating at Central) and journey times are unchanged. The spacing is pretty good, with trains at alternating 14 and 16 minute intervals. Trains to the Bay take 1 hour (vs 1hr 6 mins to Central). Sunday remains as 2tph to Central.

 

[Smwrff]

It appears that the December timetable has been loaded up for the Treherbert line.

It is shown with 4tph Mon-Sat (2tph to Cardiff Bay, 2tph terminating at Central) and journey times are unchanged. The spacing is pretty good, with trains at alternating 14 and 16 minute intervals. Trains to the Bay take 1 hour (vs 1hr 6 mins to Central). Sunday remains as 2tph to Central.

Other way around - 1hr to Central - 1:06 to Bay.

 

[snalty]

Any idea what happened to 756001 today? It was supposed to be running my commute home but a Sprinter turned up.

 

[MikePJ]

A brief piece in Modern Railways' September issue drew my attention to the release of the April TfW board minutes which mention that part of the delay to 398 introduction was caused by electrification concerns around the Intersection Bridge just south of Queen St. Quoting the minutes:

A new issue arose with Intersection bridge between Cardiff Central and Queen Street. As a contingency, testing
confirms that operations can proceed temporarily without powered OLE on the Bay Line by extending Class 398
battery usage.
Class 398 entry into service has progressed significantly. The Board were reminded that Class 398 introduction
enables fleet cascade, with the Class 756s moving to the Rhymney line.

Modern Railways asked what the issue was, and it turned out to be precautionary checks to ensure that the CVL electrification was sufficiently isolated from the main line electrification below. This led to a delay in the Bay wires being used for 398 testing, as various people noticed.

 

[5021]

A brief piece in Modern Railways' September issue drew my attention to the release of the April TfW board minutes which mention that part of the delay to 398 introduction was caused by electrification concerns around the Intersection Bridge just south of Queen St. Quoting the minutes:


Modern Railways asked what the issue was, and it turned out to be precautionary checks to ensure that the CVL electrification was sufficiently isolated from the main line electrification below. This led to a delay in the Bay wires being used for 398 testing, as various people noticed.

My understanding was that this was supposedly the reason for the delay in energising the OHL on the Cardiff Bay line rather than introducing 398s. Having said which that didn't entirely make sense as there's a HV cable rather than overhead on the Bay line at the Intersection Bridge and indeed all the way from Butetown stop northwards of course.

 

[AdamWW]

My understanding was that this was supposedly the reason for the delay in energising the OHL on the Cardiff Bay line rather than introducing 398s.

While they did indeed start running on battery on the Bay line, maybe there was a delay while they made sure that this was viable?

 

[MikePJ]

Here’s the technical explanation from Modern Railways, quoting an unnamed TfW spokesperson:

"The bridges are bonded to the main line OLE system and it was therefore necessary to separate them from the CVL electrification system from an earthing point of view, to avoid a fault on either system affecting the other.


'This has been achieved by creating a 'floating section' in the CIB [Cardiff Intersection Bridge] area for the CVL OLE system, which utilises HV cable through the area to provide the earth path for the system. This enables both OLE systems to operate independently of each other.”