The investigation of ESD charge transfers from charged insulator and the safety electrostatic potential

The ESD charge transfers from a charged insulator are investigated in this paper. Many factors including the electrode diameter, areas of charged insulator and the distance from the charged insulator which influence the charge transfers have been investigated. It has been found that the charge transfers are maximum when the diameter of the electrode is 20 mm, the areas of the insulator is about 200 cm/sup 2/ under the same potential. The relationship between maximum charge transfers and the potential of charged insulator has been found. The results show that the minimum potential of charged insulator which will ignite the flammable gases of minimum ignition energy of 0.2 mJ is about 35 kV.