TfGM - Floating Earth Package

Description

The floating Earth package of works covers the City Centre (Metrolink 1CC) and the Bury and Altrincham lines. City Centre Metrolink 1CC was constructed in the early 1990s and the traction return system utilised a diode-earthed negative arrangement and stray current collector mats to collect and guide any stray current back to the traction substation negative busbar. The diodes also provided a low impedance return path for fault current to flow from the earth to negative and therefore operate the electrical protection should a fault occur between the OLE and earth. It was therefore not considered necessary to bond any metallic assets or structures at the time of construction. The purpose of this Market Sounding exercise is; · To establish the appetite and capacity for the package from the marketplace in its currently proposed form in terms of procurement approach, delivery and technical requirements. · To obtain feedback on the proposed procurement and contracting strategy. Participation in this market sounding is voluntary, and this exercise is entirely separate from any subsequent procurement activity. Participation in this market sounding will not affect the opportunity for suppliers to participate in any subsequent procurement and will not form part of any procurement assessment or selection process. Lot 1: The floating Earth package of works covers the City Centre (Metrolink 1CC) and the Bury and Altrincham lines. City Centre Metrolink 1CC was constructed in the early 1990s and the traction return system utilised a diode-earthed negative arrangement and stray current collector mats to collect and guide any stray current back to the traction substation negative busbar. The diodes also provided a low impedance return path for fault current to flow from the earth to negative and therefore operate the electrical protection should a fault occur between the OLE and earth. It was therefore not considered necessary to bond any metallic assets or structures at the time of construction. The purpose of this Market Sounding exercise is; · To establish the appetite and capacity for the package from the marketplace in its currently proposed form in terms of procurement approach, delivery and technical requirements. · To obtain feedback on the proposed procurement and contracting strategy. Participation in this market sounding is voluntary, and this exercise is entirely separate from any subsequent procurement activity. Participation in this market sounding will not affect the opportunity for suppliers to participate in any subsequent procurement and will not form part of any procurement assessment or selection process.