Farncombe to Petersfield Resignalling Projects (GRIP 6-8)

The challenge

Originally built over 150 years ago to carry passengers between the capital and the south coast, the line between Waterloo and Portsmouth has historically been one of the UK’s busiest routes, carrying more than 40,000 passengers per day during its pre-Covid peak. Despite falling passenger numbers, it remains one of the area’s most important transport arteries, with a huge amount hanging on its ability to support a fast, efficient, and reliable train service.

Standing in the way of this, however, is the sheer age and condition of a large proportion of the route’s signalling and power infrastructure (most recently upgraded in 1974), with a rise in equipment failures and subsequent increases in both costs and maintenance requirements taking an unacceptable toll upon Network Rail, the local economy, and rail users.

The solution

Following a competitive tender process, Amaro was awarded a contract to carry out the cable installation, termination and testing works associated with the decommissioning of the end-of-life signal boxes at Farncombe, Petersfield, and Haslemere, including all necessary LV works, and the wiring, testing and commissioning of new DNOs, PSPs, feeder cables, feeder pillars, and FSPs.

Part of a much larger project to introduce digital signalling technology to the area, the role of these three signal boxes were to be centralised within a purpose-built Rail Operating Centre in Basingstoke; a state-of-the-art hub, ultimately intended to control all rail movements within the Wessex region over the next few decades.

Whilst Amaro was tasked with the procurement of the relevant power and communications cable, Alstom took responsibility for supplying all of the key signalling and E&P components, from DNOs and PSPs, to feeder pillars and FSPs. Once ready for installation, specialist lifting solutions provider, Radius Group, delivered these to site, lifting them into place and carrying out preliminary installation works in preparation for the arrival of our team.

Installation of Cabling

• The installation of new SWA/FGT cabling into existing cable trough routes as per the supplied drawings, schedules, and specifications, pulling them into place by hand or by means of an electric winch, assisted by cable rollers positioned along the route. Once installed to the desired position, the cables were then cut to the appropriate length, fitted with temporary identification tags, and sealed before being temporarily secured to the trays or laid within the troughing routes. Once all cables within a specific group were installed, the tie wraps were then used to permanently secure them, with the cables then being connected up to the relevant piece of equipment.

Testing and Commissioning

• All new accessories (e.g. DNOs etc.) were terminated in accordance with the manufacturers’ recommendations. Once complete, the associated cabling was tested for resistance and continuity in accordance with BS7671 with the results being recorded on the NICEIC schedule and within the appropriate ITP. Working in accordance with our own safe isolation procedure, any cables or accessories that were not ready to be brought into use immediately had an isolation applied, with all new supplies from the existing distribution boards being labelled in accordance with BS7671. All testing was carried out as per the requirements of Network Rail’s Site Acceptance Testing Schedule.

Site Walkout and Snagging

• Following best practice, not to mention Amaro’s policy of taking a belt and braces approach to all installation works, a site walkout was carried out in each location, inspecting the installation of new DNO, LVAC, and TX equipment prior to handover.

DNOs, TX, FSPs and Power Pillars

• Amaro was charged with carrying out new cable terminations and testing within FSPs, joint boxes, DNOs (including service transfers) and transformers from various LVAC panels and DNO supplies. The cable terminations consisted of FGT and SWA cables from the power pillar to the FSPs, from the DNOs to the FSPs, and from the LVAC panels to the 400-650v transformers and, from there, to the power pillars. All works were carried out in accordance with SIH standards NR/L3/SIG/11303 modules 1D15 and 1D20.

LVAC Alterations

• All LVAC alterations were completed as per the AFC design with any alterations taking place within the substation location falling under the supervision of a level A operative supplied by the client.

Signal Box Works

• Prior to the full decommissioning of the three signal boxes, a programme of ‘tag and trace’ was implemented in order to provide a detailed understanding of the existing circuits.
• Hand traced by a team of Amaro electricians and with each circuit then being labelled, the designer was provided with a detailed picture of all circuits in readiness for decommissioning and enabling.

Basingstoke ROC

• A programme of cabling, upgrades and modifications was also required relating to the ROC itself, including but not limited to the equipment room, operating floor desk, and simulator room.

The outcome

Whilst works were initially due to come to an end in January 2024, this estimate has since been revised to October 2024. Having impressed the client with the accommodations and flexibility of our team, not to mention the quality of the works delivered on site, Alstom has entrusted Amaro with a significant uplift in our scope of work, increasing the remit and value to the business by more than 50%.

This project case study will be updated at project completion.