Understanding Your Breaker Panel
The breaker panel (service panel) is the control center for your home's electricity. Knowing what its parts do helps you find outages quickly, avoid overloads and recognize danger signs. The inside of the panel, however, is for qualified electricians only.
- Homeowners
- Renters
- New Home Buyers
- Landlords
What is in the panel
- Main breaker: a large breaker, usually at the top, that shuts off all power in the home. Know where it is.
- Branch circuit breakers: smaller switches that each protect a circuit (a room, appliance or group of outlets). They trip to prevent overheating wires from overload or short circuits.
- Double-pole breakers (two switches joined) for 240-volt appliances such as dryers, ranges and water heaters.
- GFCI breakers: detect small leaks of current to ground and trip to prevent shock, used in wet areas.
- AFCI breakers: detect dangerous arcing in wiring and trip to prevent fires, used on many bedroom and living circuits.
- The panel cover (dead front) covers live bus bars and wire connections. Behind it, the main lugs stay energized even when the main breaker is off in some panels.
Breakers protect wires and equipment from overheating. Only GFCIs protect people from shock. See Home Electrical Safety.
What homeowners can do
- Label every circuit clearly (kitchen outlets, bedroom lights, etc.). Have an electrician or a helper test each breaker to be sure labels are right.
- Reset a tripped breaker by pushing it fully to OFF and then ON. Stand to the side, with dry hands, and look away. If it trips again right away, stop and find the cause. Unplug devices on that circuit first.
- Know why breakers trip: too many devices on a circuit (overload), a short circuit, a ground fault, or an arc fault. A tripping breaker is a warning, not a nuisance.
- Test GFCI and AFCI breakers monthly using their test buttons, and replace those that fail.
- Keep the area clear: codes call for a clear working space in front of the panel, generally at least 30 inches wide and 36 inches deep, with no storage, shelves or water heaters in the way. See Garage Safety.
- Keep a flashlight near the panel and teach family members where it is and how to shut off the main in an emergency. See Shutting Off Utilities.
Don't
- Don't remove the panel's dead-front cover unless you are a qualified electrician. Live parts inside can cause shock, burns and arc flash. See Arc Flash.
- Don't put a bigger breaker on a circuit to stop it tripping. The wire may overheat and start a fire.
- Don't tape or bypass a breaker or leave a tripped breaker held on.
- Don't double-tap (put two wires on a breaker that allows one), or add circuits without a permit.
- Don't spray or wash near the panel, or work on it with wet hands or on wet ground.
Warning signs: call an electrician
- Burning smell, scorch marks or melted plastic at the panel or breakers.
- Buzzing, crackling or humming, or breakers that feel hot.
- Rust or moisture in the panel, or water entering.
- Frequent tripping, lights that flicker or dim when appliances start.
- Breakers that won't reset or feel loose, or fuses that blow often.
- An old panel (over 25 to 40 years), a fuse panel, or certain brands that have had reported failures to trip, such as some Federal Pacific Stab-Lok and Zinsco panels. Ask an electrician to evaluate.
- Adding major loads like an EV charger, hot tub, solar or an addition may require a panel upgrade. See Home EV Charging.
Breaker panel checklist
- I know where the main breaker is and every circuit is labeled
- I reset tripped breakers safely and investigate repeat trips
- GFCI and AFCI breakers are tested monthly
- The area in front of the panel is clear
- I never remove the panel cover or oversize a breaker; I call an electrician for warning signs
Standards & references
Last updated: