Leveraging the advantages of a containerised solution, Zest WEG Group company Shaw Controls has provided an optimal medium voltage switchgear solution for the supply of power at a copper mining project in the Democratic Republic of Congo.
The WEG MTW05 MV switchgear, the first to be supplied by Shaw Controls into a mining project in Africa, was installed at the Kamoa-Kakula project in the DRC’s Katanga province, located 25 km west of Kolwezi and 270 km west of the provincial capital of Lubumbashi.
“Our engineers provided an innovative design solution to incorporate the switchgear into a standard 12 metre container, which is more cost effective than fabricating an E-house from scratch,” says Kirk Moss, medium voltage manager at Shaw Controls. “The dimensions of a container make it far easier to transport and to install on site, giving the customer a convenient ‘plug and play’ solution.”
The design was able to fit a 31,5 KA withdrawable metal-clad board into a containerised solution, with innovations that allow back access without compromising on the available space.
“The fully withdrawable circuit breakers and voltage transformers (VTs) make the design ideal for a container, while also improving the ease of maintenance of the circuit breakers and VTs,” says Moss.
The WEG switchgear offers a number of features that are particularly advantageous. For instance, the panel has an arc resistant design with internal arc classification (IAC) of BF ALR 31,5 kA for one second. This is a major safety related feature which not only ensures safer working conditions for personnel but reduces the amount of personal protective equipment they require when working on the system.
“Safety is always paramount in the engineering of solutions by Shaw Controls, and this one is no different,” he says. “In the case of an arc explosion, the gases are vented through an internal tunnel running the length of the board. This way, the gases can be ducted out of the sub-station, further enhancing safety. It also means that little clearance is required above the panel, which saves space.”
The panel also boasts a short-time withstand rating of up to 31,5 kA for three seconds, a considerably high fault level for a panel of this size. The range of WEG MTW05 panels is available in voltages of up to 17,5 kV and currents of up to 2,500 Amps.
The full containerised solution was manufactured at Shaw Controls’ 12 000 square metre facility at Robertsham in Johannesburg, which is manned by a team of skilled technical personnel. A full factory acceptance test was conducted at the company’s premises prior to its dispatch to the mine; with its ‘plug and play’ design, the installation was able to be easily conducted by the mine itself.