The BPOJ series of flameproof and intrinsically safe combined variable frequency starters for mining applications are suitable for loads such as belt conveyors, emulsion pump stations, and shield machines in coal mine shafts with a rated voltage of 1140V. Each combined variable frequency starter integrates multiple variable frequency circuits and a power frequency starter circuit, enabling centralized control of all motors within the load and providing 127V control power for the control system.