... fly start again without impact. Flying start[OPTIONAL FUNCTION]. Main circuit is connected to the controller by optical fiber, which make ... over voltage, over current, low voltage, phase loss, over load, over heat, earth fault, and short circuit. The failures of VFD include ... fan, Bag house fan, Raw mill fan, Lignite Mill Filter Fan, By Pass Filter Fan, Kiln. Mining: Conveyor, Lift, Pump. Water: Pump. ...