(VSD) in a multi- drive configuration and built for driving one dual pinion ball mill of 9500 kW (2x 4750 kW) Plus 150% starting overload or one min. The overall footprint of this VSD is very compact (LxWxH) 5200 x 1400 x 2700 mm, compact footprint of VSD leads to that the electrical rooms will be reduced in size. This VSD is also designed with pressure Relief Ducts, the by-products of arcing will be directed away from the front of the enclosure and will be expelled vertically through arc vents located at the top of the enclosure.