Your electrical panel is a labeled map of every circuit in your home. The main breaker at the top tells you your service size (100A, 200A). The numbered switches below it each protect one circuit — 15A for lights, 20A for outlets, 30A–50A for heavy appliances. 5 feet (≈ 2 meter) high in front of the panel. These two sizes typically account for 60-70% of all breakers in a standard home electrical panel, with 15 amp breakers protecting general lighting circuits and breakers. It's usually the largest switch in the panel and should be labeled “Main” or “Service Disconnect. That number tells you how much electricity your panel is designed to. The wires within the switch are connected to the home's consumer unit and light fitting through electrical cables hidden in the walls and ceilings.
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