Around the house · Easy · about 10 minutes (about an hour to label a whole panel)

Reset a Tripped Circuit Breaker

When part of your home suddenly loses power, a circuit breaker has often switched itself off to protect the wiring. Knowing where your breaker panel is, how to reset a breaker, and which breaker runs which room saves time in the dark. This guide is for U.S.-style breaker panels and covers only the switches a homeowner is meant to use.

When to teach it: Watch from about 7, help from about 10, do it alone from about 13.

A tripped breaker sits in the middle or at OFF. Push it firmly to OFF, then back to ON. Handle positions and labels vary from panel to panel.

You'll need

Flashlight
Pen and paper, or the label card inside the panel door
Masking tape (optional, for labels)
A helper (for labeling the panel)

Before you start

If you see sparks, hear sizzling or buzzing, or smell something burning, don't go near the panel. Call the fire department right away.
If the panel is wet, or you can see any wires, don't touch it. Call a licensed electrician.
Turn off the lights and unplug appliances in the rooms that lost power.

Step by step

Tick each step as you go if you like; ticks stay on this device.

Notice what went darkWalk around and note which lights and outlets stopped working. Turn off the light switches and unplug appliances in those rooms, so nothing switches on the moment power comes back.
Find the panelIn many homes, especially older ones, the panel is in a garage or a storage closet. Some homes have more than one panel, inside or outside.
Spot the tripped breakerOpen the panel door. Breakers are rows of small switches. A tripped one sits all the way at OFF or stuck partway between ON and OFF.
Push it fully OFFStand a little to the side of the panel. Using one hand, push the tripped handle firmly all the way to OFF.
Switch it back ONNow push the handle firmly to ON. Close the panel door.
Check and spread the loadSee if the lights and outlets work again. Plug things back in one at a time, and spread big power users across different circuits instead of running them all on one.
Stop if it trips againIf the breaker trips again right away, or you can't figure out why it tripped, leave it OFF and call a licensed electrician.
Label the panelOn a calm day, with a helper, switch off one breaker at a time and note which lights and outlets go dark. Write the rooms on the panel's label card. Warn everyone first, since clocks and computers will lose power.
Show the familyShow everyone in the household where the panel is and what a tripped breaker looks like.

Physics

How it works: Why a breaker trips

Electric current is the flow of electric charge through a wire, measured in amps. Voltage is the push that moves the current, measured in volts. In standard U.S. homes, regular outlets supply 120 volts.

Power, measured in watts, tells how fast a device uses energy. You find it by multiplying volts by amps. Each breaker protects one circuit and allows only a set number of amps. If more current flows than that, the wires could get too hot, so the breaker switches itself off. That's called tripping.

Here is the math for a 15-amp circuit: 120 volts × 15 amps = 1,800 watts. Say your space heater's label says 1,500 watts and your microwave's label says 1,000 watts. Together that's 2,500 watts. Divide by 120 volts and you get about 21 amps, which is more than 15. Click: the breaker trips.

watts = volts × amps (so amps = watts ÷ volts)

Try it: With an adult, find the labels on three unplugged appliances, like a lamp, a toaster, and a hair dryer. Write down each one's watts and divide by 120 to estimate its amps. Which two together would go over 15 amps?

Keep learning: Science

Teaching it to your kids

Visit the panel together in daylight, long before you ever need it.
Let your child hold the flashlight and find the tripped switch while you reset it.
Make labeling a team project: one person flips breakers, the other walks around and reports what went dark.
Turn appliance labels into a math game with the watts formula.

Tips

Keep a flashlight near the panel.
Write down each time a breaker trips and what was running. A pattern helps an electrician find the cause.
Extension cords and power strips are for temporary use only.
Don't run a space heater on a light-duty extension cord. It can't carry that much current.

Common mistakes

Mistake	Instead
Resetting the same breaker over and over.	A breaker that keeps tripping is a warning sign. Leave it off and call a licensed electrician.
Pushing a tripped handle straight to ON, and nothing happens.	Push it firmly all the way to OFF first, then to ON.
Running a space heater and a microwave on the same circuit.	Spread high-wattage appliances across different circuits.
A panel with no labels, so you guess in the dark.	Map and label every breaker now, while the power is on and nothing is wrong.

Safe habits

Never touch a panel that is wet. Call an electrician.
If you can see any wires in the panel, stop and call an electrician.
Use extension cords and power strips only for temporary needs.

When to call a pro

Call a licensed electrician if a breaker trips again right after you reset it or keeps tripping.
Call an electrician instead of resetting if the panel is wet, you can see wires, or more than one breaker has tripped.
Call a licensed electrician soon if lights dim or flicker, or if outlets, switches, plugs, or cords feel unusually warm.
If you see sparks, hear sizzling or buzzing, or smell something burning, call the fire department right away.

Sources

Free how-to guides for families, with nothing to earn, pass or send in. They follow U.S. rules and sources; your owner's manual, product labels and state and local rules come first.