Until recently, providing power to the tens of thousands of stands built every year at the National Exhibition Centre (NEC) was a complicated, time-consuming and labour intensive process involving thousands of metres of temporary cables being installed by an army of electricians. That has now changed, thanks to a fully automated control system designed and installed by Gloucestershire-based Severn Controls.
Severn proposed controlling the entire power supply via a SCADA (Supervisory Control and Data Acquisition) system using bespoke software that would provide greater flexibility and allow many more functions to be automated. The system will eventually allow the NEC to switch power on and off, allocate single or 3-phase current, limit supplies and monitor power consumption. Indeed, the new electrical infrastructure, called ‘Plug & Play’, started to provide power to NEC exhibitions earlier this year, and is part of the centre's £40m venue improvement programme.
Setting up manually used to take up to two weeks and only then could carpets be laid and contractors begin to think about building up the stands. Prior to the exhibition opening, the contractor needed to enter subways beneath the halls to insert fuses and turn on power to the stands. These supplies remained live until the mains team moved in to isolate the services at the end of each day. Apart from the expense of mobilising teams of electricians in this way, energy was also being wasted while the electricians made their way back to the subways to isolate the supplies. At the end of the exhibition during stand break-down, the cables had to be disconnected and put into storage, ready for a repeat procedure at the beginning of the next exhibition.
Contrasting the old with the new not only highlights the significant advances in control technology since the 1970s when the NEC was built, but also demonstrates the enormous potential of a SCADA installation. Using PLC and SCADA packages supplied by Mitsubishi Automation, Severn Controls created a fully automated system, including a bespoke booking/configuration utility written as a vb.net web application (SQL 2005 Database).
The entire NEC is now pre-wired. Sixty-five electrical distribution panels are installed within the subways and almost four thousand 63A sockets permanently fixed in the various ducts. The sockets are hardwired back to the distribution panels and their locations indicated on the SCADA screens. Pulling points are provided in the floors of the halls to facilitate power connection to stands via extension cables.
NEC mains teams are enthusiastic about the new system. It is far more flexible than the old because fixed sockets are so much easier to locate, and faults are easier to find and rectify. Moreover, both the NEC and its customers benefit from the greatly enhanced functionality of the system and the vast amount of information it is able to provide.
For example, it is now much easier, and therefore quicker, to identify power supply problems, even on individual stands. Previously, faults reported to the exhibitor helpdesk were passed to the mains section and, if confirmed, an engineer was despatched to the subway to check the supply and, if required, change the fuses (the most likely cause of a breakdown). Now, even before the exhibitor can contact the helpdesk, the operator knows what the problem is and may already be making arrangements to remedy it, which all adds up to quick and efficient power restoration.