Normally the neutral-to-ground bond is made in the main electrical panel and not in sub panels, lest grounding conductors end up carrying current during normal operations - a shock hazard. Confusion often arises when connecting the neutral and ground conductors within a breaker box, as their proper handling depends entirely on the panel's location within the electrical system. Floating Neutral conditions in the power network have different impact depending on the type of Supply, type of installation and Load. Mixing neutral and ground wires can result in serious safety hazards: If the neutral and ground wires are shared, it can lead to appliances' metallic parts becoming live (carrying current). When there's a fault, instead of safely directing the current to the earth, the combined neutral-ground. A loss of neutral in the grid, while not always a cause for immediate concern, can have potentially life-threatening consequences in certain situations.
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