What is the significance of a low resistance reading on a ground system test?

A low resistance reading on a ground system test is significant because it indicates a good connection to ground. This means that the grounding system is effectively providing a low-resistance path for fault currents to flow safely into the earth. This is vital for the safety of electrical installations, as it helps to prevent electric shock hazards and ensures that overcurrent protection devices, like circuit breakers or fuses, can operate correctly in the event of a fault.

When the resistance is low, typically below 5 ohms, it confirms that the grounding electrodes are functioning properly and are well-connected to the earth, which facilitates efficient operation of the grounding system. This low resistance enhances the system's ability to dissipate electrical surges and faults, thereby providing stability and protection for equipment and personnel.