||Simple design. Easy to install in good soils. Hardware readily available.
Can be extended to reach the water table.
||High impedance. Hard to install in rocky soil. Step voltage on earth
surface can be high under large fault currents or during a direct
||Can achieve low resistance contact in limited area.
||Most difficult to install. Should be installed vertically.
|Horizontal bare wires
|Low impulse impedance. Good RF counterpoise when laid in star pattern.
||Subject to resistance fluctuations with soils drying. Not recommended
with unstable soils.
|Can achieve very low resistance in certain applications.
||Little or no control over future alternations. Must be employed
with other electrodes, not as sole electrode.
||Straightforward design. Easy to install around existing
facility. Hardware readily available. Very efficient due to volume.
||Problems with asphalt and concrete around the facility?
Not desirable where large rocks are near surface.