What characteristic should protective grounds have?

Protective grounds should have low resistance to ensure that any fault current is effectively and safely diverted to the ground. This characteristic is crucial because a lower resistance allows a quicker and more efficient path for the electrical current to flow into the earth, minimizing the risk of electric shock to workers and reducing the likelihood of damage to equipment. The low resistance helps to stabilize the electrical system during fault conditions and allows protective devices, like circuit breakers, to operate correctly, ensuring the safety of linemen working on or near energized systems.

Having high insulation, high voltage, or low energy consumption would not provide the necessary safety or effectiveness in grounding practices, as these characteristics do not contribute to the efficient management of fault currents in electrical systems.