Test equipment: AEMC’s GroundFlex® Field Kit includes the GroundFlex® Adapter Model 6474 and Ground Resistance Tester Model 6472. This is the ONLY system on the market capable of testing ground resistance of individual power transmission tower legs, as well as total resistance without disconnecting the overhead ground wire – this alone is a huge time and money saver, not to mention a major safety improvement.
Key features include testing both ground resistance of tower legs (individually and total) and overhead ground wires. This system tests leakage current through the tower legs and tests at frequencies up to 5kHz to profile impedance, which is important to characterize for lightning strikes.
Tower testing with the Models 6472 and 6474 consists of four main steps:
1. Check the placement of the instrument’s test electrodes.
2. Check the integrity of the tower’s ground connections.
3. Perform active measurements on the tower's footing impedance and overhead ground conductor.
4. Verify the measurement results with a 4 pole earth impedance (lattice network) test.
The first two steps must be completed successfully (including making any required adjustments to bring measurements within the suggested ranges) before you can perform active testing on the tower.