Partial earth bonding resistance with single flex clamp method

Industrial installations

Some locations need particularly thorough protection from outside disturbances, and Faraday cages are amongst the most effective types. Lightning protection on buildings with Faraday cages or other metal shields is connected to the conductive construction of the building. It must be tested periodically to check the connections the whole way from the lightning rods to the grounding nets.

Conductive paths through the building must evenly dissipate power of the lightning strike all the way down to the ground. This way the voltage drops during lightning discharge throughout the building will then be low enough to protect living beings and inbuilt equipment.

The testing is executed using a high current. The power is controlled by using a pulsed waveform for safety of the operator and any bystanders. The current in each leg of the is measured using a flex clamp, using multiple loops if necessary, to achieve high resolution. The partial current is measured during the generated pulse. The test leads must be firmly attached to the measured surfaces using robust G-clamps that can puncture colour or rust to conduct the current pulse well. Additionally a measurement of touch voltage can be done using a body resistance simulator. It adds a measure of danger to human life.

High current dR 300A testing with MI 3144 Euro Z provides enough power while still being small and portable enough to be easily brought to any roof or part of industrial platform. External flex clamps can be wrapped around any metal leg or construction with high cross-section. Partial currents through building’s construction, metal straps or cable screens can be evaluated.

Synchronized testing of voltage drops in the building’s surroundings during the generated high current pulse shows potential risks in case of a bad connection to the grounding net due to aging, corrosion or mechanical damage.

Flex Clamps measure selective currents to the ground during generated pulse.

Robust G-clamp connects the test leads through colored or rusted surfaces to conduct hi test current to grounded paths. 

Portable protected travel case to transport all the necessary equipment to the test site.



MI 3144 Euro Z 800 V