Ageing bus duct replacement – Parmelia House, 191 St Georges Terrace, Perth

Ageing Bus Duct Scope of Works,

Parmelia House is a 20-story A-grade commercial office building located in the heart of the Perth CBD. The client had identified a requirement to replace an ageing bus duct supplying the mechanical services switchboard located in the plantroom on the 20th floor, which dated back to the original construction of the building and had reached end-of-life. After participating in a competitive tender process Infrared Services was the successful electrical contractor.

The project required that the existing bus duct remains in service for the duration so as not to disrupt building services. A cable tray was installed within a vertical air riser shaft, and eight (8) 300mm2 XLPE cables were reticulated up the shaft originating at the site main switchboard and terminating at the main mechanical services switchboard. The total length of the cable run was approximately 170 metres. All installation work was required to be completed with no disruption to the normal operation of the mechanical plant. When the installation of the cable tray and cabling was completed, a building shutdown was coordinated with the network operator to isolate the site main switchboard and terminate the cabling at both ends. Termination was completed with less than 10 hours of downtime for the site.

Challenges included; significant risk management when reticulating cable lengths weighing more than 500kg up a 100m vertical shaft, carefully operating within a live commercial building while eliminating any disruption to the tenants, coordinating isolations with the network operator, and working to tight deadlines to ensure work was completed in a timely fashion. The total project value was approximately $170k.