Common grounding refers to the practice where a system's functional (working) grounding, equipment protective grounding, and lightning protection grounding share a single grounding electrode system. Alternatively, it may mean that grounding conductors from multiple electrical devices are connected. Common Grounding is the interconnection between the grounding system of different electrical systems, devices, and machines that provides a common path for all to flow the fault current to the ground. This common grounding. Say I want to have one 2 gang box that has a 120V 20 Amp circuit and a 240V 20 Amp circuit present. For safety, and convenience I would run a 3 phase breaker for these 2 circuits. Whether you're a seasoned pro or just starting out, this comprehensive guide will give you practical. A common ground refers to a single point in the circuit where multiple components, such as switches, lights, and appliances, are connected. This point is typically the ground wire, which is connected to the earth or a grounding rod for safety reasons.
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