VFD s in mining operations are becoming more and more common. EMA has both sold and serviced the mine VFDs. 
EMA has installed and serviced VFDs in mines. (See this recent article about a Toshiba Medium Voltage VFD )
Mine VFDs are used for pumping, for ventilation, for the actual mine process, and for transport. Especially in pumping and air handling applications, VFDs can be significant energy saving devices, allowing a mine operator to keep more of his hard earned profits.
EMA has the highest customer satisfaction rating of anyone in the drive industry, and you can put us to the test by calling 800-848-2504800-848-2504, or just by hitting the contact icon on the bottom right of this page. We both sell and repair VFDs used in mining applications.