Ross Engineering Corporation has developed and manufactures a line of Electrostatic Discharge (ESD) testers. One model is designed for explosive proof testing per MIL-I-23659C, Paragraph 4.4.3.2 static discharge test. It incorporates high voltage electro magnetic or air pressure operated relays to safety ground, charge, and dump capacitors into the appropriate device under test. This ESD tester is a portable system utilizing 120V AC power. It is a high reliability device capable of many thousands of cycles.