When is a bond required for electrical equipment?

A bond is required for electrical equipment primarily to reduce the risk of electrical shock. Bonding refers to the practice of connecting all metallic parts of electrical systems together to ensure that they are at the same electrical potential. This is crucial for safety because it prevents any metallic component from becoming energized during a fault condition, which could lead to an electrical shock hazard for individuals who come into contact with those components.

Proper bonding helps create a low-resistance path for fault currents to flow back to the source, allowing protective devices such as circuit breakers to operate effectively and disconnect the power. By doing so, it enhances overall safety within the electrical installation, minimizing the risk of injury.

In contrast, other options such as the presence of unbalanced electrical loads, ensuring perfect current flow, or the presence of static electricity do not directly relate to the primary purpose of bonding, which is safety against electric shock. Unbalanced loads may have their own implications, but they are not the reason bonds are specifically required for equipment. Similarly, achieving perfect current flow is not a function of bonding, and while static electricity can pose risks, bonding is focused primarily on mitigating shock hazards from fault conditions in electrical systems.