If you’ve ever plugged in one too many holiday lights, switched on a vacuum, or cranked up a space heater only to have the lights or appliance suddenly shut off, you’ve created an electrical circuit overload. The shutdown was triggered by the circuit’s breaker (or fuses) in your home’s service panel.
And while circuit breakers are reliable and do a good job preventing house fires due to overloads, the safest strategy is to manage your electricity usage to avoid overloads in the first place.
This article will tell you how to sort out the circuits in your electrical system and avoid overloads. You’ll avoid not only occasional blackouts but also avoid chronic overloading when you expand your system to include additional outlets, light fixtures, or holiday lights.
Understanding The Circuit
Every socket in your home is connected to the breaker box. There will be a limited number of sockets on each circuit, and the exact amount will depend on the rating of the breaker in the box; commonly, this will be 15, 20, or 30 amps.
The short version is that you can plug anything into each circuit, but as soon as the amps are drawn, go higher than the breaker, and it will trip. In effect, the circuit has been overloaded.
This is a safety feature. If the circuit is overloaded and the breaker doesn’t trip, the wires will get hot, and this can result in the plastic coating melting, leaving the system vulnerable to short circuits, electric shocks, and even starting a fire.
What Is an Electrical Circuit Overload?
Electrical circuits are designed to handle a limited amount of electricity. Circuits are made up of wiring, a breaker (or a fuse in old wiring systems), and devices (such as light fixtures, appliances, and anything plugged into an outlet).
The electricity usage of each device (when running) adds to the total LOAD on the circuit. Exceeding the rated load for the circuit wiring causes the circuit breaker to trip, shutting off the entire circuit’s power.
If there were no breaker in the circuit, an overload would cause the circuit wiring to overheat, melt the wire insulation and lead to a fire. Different circuits have different load ratings, so that some circuits can provide more electricity than others.
Home electrical systems are designed around typical household usage, but there’s nothing to prevent us from plugging in too many devices on the same circuit. However, the more you know about your home’s circuits’ layout, the more quickly you can prevent overloads.
Signs of Overloaded Circuits
The most obvious sign of an electrical circuit overload is a breaker tripping and shutting off all the power. Other signs can be less noticeable:
- Dimming lights, especially if lights dim when you turn on appliances or more lights.
- Buzzing outlets or switches.
- Outlet or switch covers that are warm to the touch.
- Burning odors from outlets or switches.
- Scorched plugs or outlets.
- Power tools, appliances, or electronics that seem to lack sufficient power.
Buzzing sounds, burning smells, and unusually warm devices also can indicate other wiring problems, such as loose connections or short circuits. If any of these problems persist after you’ve taken steps to prevent circuit overloads, contact an electrician.
Know your panel
The switches (circuit breakers) inside that gray metal box consist of two different types: dedicated and general-purpose circuits. The former have their work cut out for them: they power such “big draw” appliances as your furnace, gas range, and microwave or serve “big draw” rooms such as kitchens and laundry rooms.
General-purpose circuits can serve multiple rooms and hallways. These are often (but not always) the types of circuits that you can plug into for that extra power when everything goes dark or use to add an outlet.
Perfect your house map
But first, a floor plan awaits you. Ideally, one is already taped to your electrical panel so that you can easily trace which rooms—and which outlets—run to every circuit in the electrical panel.
At Experts In Your Home, we find that many home maps are good at identifying dedicated circuits but are not so good at labeling general-purpose circuits.
In this case, there is no “easy” way to bring order to your home’s electrical system. You’ll have to turn off the circuit breakers and move methodically through your home, testing every outlet by flipping switches on and off and plugging in devices.
There’s no doubt that the electrical repair will go faster (and you’ll have more fun) by working with a partner. While one person “mans” the panel, the other can assume the role of outlet tester.
Fixing The Overloaded Circuit Yourself
The first sign that you’ve overloaded a circuit is when the breaker trips and the power goes out. You’ll need to check the breaker box and find out which switch has turned off; do not turn it back on yet.
Once you know the circuit, you can unplug everything plugged in on that circuit and turn off any lights.
At that point, you should be able to turn the circuit back on.
The next step will be to start plugging things back off. You may find that one appliance causes the breaker to trip again. This could mean there is a fault with the appliance.
To check this, plug the appliance into a different circuit and see if it makes a different breaker trip. If it does, you have a problem with the appliance and not the circuit. You’ll need to have an electrician either repair it or you’ll need to replace it. Contact the Electrical Services for more information.
If you’ve managed to plug everything in without the breaker blowing again, then you have a potential overload. Don’t forget that just because everything is plugged in doesn’t mean it is all drawing power at the same time.
You can look at each appliance on the circuit and make a note of the amps it draws when in use. It should then be possible to add these figures up; if they total more than the breaker’s value, you can overload the circuit; when all the appliances are on.
Always apply for an electrical permit from your local building inspections department when you undertake an electrical project. The permit not only ensures that your work will be inspected for proper technique and safety but also that you’ve properly analyzed your home’s circuitry and are following a sound plan.