The Network Rail Welsh Independent Feeder from Newport to Cardiff was successfully designed and Installed by Enable Infrastructure and Enable Powers Systems.
25 February 2021
The Network Rail Welsh Independent Feeder from Newport to Cardiff was successfully designed and Installed by Enable Infrastructure (formerly known as BCM Construction) and Enable Power Systems (formerly known as BCM Powers systems).
The final pressure test was completed over the weekend, allowing Network Rail to energise and determine if the application under SOAK testing can sustain the continuous load.
Enable Infrastructure collaboratively with Enable Power Systems successfully designed (GRIP 5 Detailed Design), installed, terminated, and tested the new 15km, 25KV High Voltage Independent feeder 8501. This includes 14500metres of cable management route from St. Brides Auto Transformer Feeder Station (ATFS) to Canton ATFS. The project formed part of the Great Western Electrification Programme (GWEP) where Enable Infrastructure self-delivered and acted as the lead Tier 1 Principal Contractor.
This is now the second Independent Feeder Commission Enable Infrastructure have constructed using our in-house capabilities throughout GWEP. The original feeder being Network Rails largest HV Feeder route in the UK from Royal Wootton Bassett ATFS to Thingley Junction ATFS totalling a distance of 23km.
The key objectives of this project were to provide independent feeder cables from National Grid Supply Point sites to the remote ATFS locations. In this instance, St. Brides ATFS has a local National Grid Bulk Supply Point (BSP) and Canton ATFS is the remote ATFS. Enable Infrastructure were also part of the civils installation to St Brides ATFS substation and all associated construction of the access Haul Roads into site.
The Welsh independent feeder cables distribute bulk power at 50kV without the requirement for the contact system to be energized. The independent feeder cables shall be operated as a 2phase, +25kV, -25kV supply, switched by double-pole switchgear at both ends. Neutral is provided by the common bonded AC traction return earth.
The installation consisted of:
- 6188m TTS 200 Ground Route
- 6585m Arco raised route Post Route.
- 4no. Under RRAP Crossing
- 2no. Four road under track crossings
- 1no. One road under track crossing
- 1no. Over track crossing gantry
- 29900m 1-core 630mm² Cable
- 118no. Sheath Testing undertaken
- 66no. Inline Joints
- 34no. Shield Break Joints
- 19no. Link Box Installations & Surge Voltage Limiters (SVL)
- Pressure Testing
- 19no. Spider Plates
- All associated bonding
Planning the delivery was essential as the works took place simultaneously with the OLE installation works by others, working around new piling and stanchion works had to be coordinated in both installation, methodology and design integration.
With the installation of the Catenary also going ahead, Enable Infrastructure had limited access throughout the length of the route. With this constraint, all cables were installed with the use of RRV working between OLE team worksites.
Enable Infrastructure also introduced a new Link Box to be used on this project and worked with Network Rail in getting the PADS approval. This product allows better access for maintenance and is purpose-built for 2 phase HV systems rather than the adaption of 3 phase link boxes.
We have also carried out training to the local NR maintainer on the new Link Box and Surge Voltage Limiters regarding both installation and maintenance.
The design, plant and materials of this project formed part of our in-house Enable Consortium reinforcing quality control (Design: Enable Design (formerly known as Equate Design), Plant: Enable Hire (formerly known as CHS) Materials: Enable Infrastructure). This resulted in the successful delivery of the multidisciplinary Tier 1 project.