Rappers are utilized to dislodge material from the collecting surfaces, discharge electrodes and gas distribution plates. Improper rapping can lead to spark-over and a reduction in power levels, high resistance grounds and dead short conditions, reentrainment of collected material, damage to ESP internal components and distortion of gas flow. Coils are wound from class (160) copper wire. The Migi is capable of delivering strong shearing forces to remove even the most tenacious of dusts from collecting curtains and rigid mast designed high voltage systems.