Computer controlled, portable, robust and designed for use on the shop floor. These units test Electrical Earth Bonding circuits, Structural earth bonding, and ground bonding Loops.In modern aircraft the requirement for a secure and guaranteed integrated grounding circuit is more important than ever.An ineffective ground circuit can result from incorrect assembly or a material defect at manufacture, and degradation of material and joints through the lifetime of the aircraft.An effective ground circuit is essential in protecting the aircraft from the damaging effects of ; stray currents caused by faulty systems, lightning strike that can cause massive currents to pass from the aircraft fuselage to systems and wiring, and HIRF High Intensity Radiated Fields that can cause voltage transients and malfunction of aircraft systems.In each aircraft there are thousands of bonding points and ground circuits, all need to be tested to ensure a low resistance path.