A few days ago a reader named Marcus asked me about electrical wiring while I was doing one of my new live video broadcasts. The live video is so much fun because I can interact with people in real time like we’re sitting at a table enjoying lemonade or iced tea. Each of my livestreams is recorded so if you can’t watch it live you can replay it later.
Marcus’ situation is one that I see happening to you. This is an extremely important teaching moment in case you know little about how electricity works in your home and how dangerous it can be if not installed correctly. It is important to realize that although electricity is a very nice thing to have in a home, it should be respected.
I went to the National Fire Protection Agency and found that hundreds of people die each year in the United States from electrical fires. Thousands are injured. Over $ 1 billion in direct property damage is attributed to electrical fires in any given year. This should put your head on a pivot.
The NFPA has a rich history, but it was primarily the insurance industry that created it. Insurance companies have realized the need to educate people on how to prevent fires. As electricity became available in homes, insurance companies saw that they had to do their best to make sure that electrical wires and cables in homes were safe and that fires kept fires. were reduced to a minimum.
The National Electricity Code was born from this initiative. The NFPA publishes the NEC. It is a proven document that describes the minimum standards by which electricity should be installed in homes, businesses and other buildings.
What is the relationship between you and Marcus? He wanted to know if he could mix and match different sizes of wires on the same circuit. You should know that the wires inside your house cables come in different sizes, much like shoes or t-shirts. The size is called the wire gauge. The most common wire gauges used in residential buildings in the United States are 14, 12, and 10. This can be confusing because as the number decreases, the diameter of the wire increases.
The wire size, as well as the insulation covering the wire, has been tested and rated by the NFPA. For example, 14 gauge wire is rated at 15 amps or 1800 watts in the United States. The 12 gauge wire is rated at 20 amps or 2400 watts. The wire that feeds your electric dryer is almost always a 10-gauge wire. Plus, your electric dryer runs at 240 volts while most other appliances in your home run at 120 volts.
Hang on with me. Here is the reward. If you go to your electrical panel, you will probably see those funny levers that are circuit breakers. The circuit breaker really looks like a wall switch that you use to control a ceiling light. Circuit breakers are rated by amps, and you can see that number on the actual breaker. Look at yours. You will see a lot of 15’s and 20’s.
Most of the breakers in your panel will be single pole breakers. Only one wire is connected to the base of the circuit breaker. In a normal circuit in your home, this wire leaves the panel and begins to daisy-chain to wall outlets and possibly some lights. If the circuit breaker is rated for 20 amps, the wires in this circuit should be 12 gauge. You would never want a piece of wire in this 20 amp circuit to be 14 gauge wire.
Here’s why. Normal circuit breakers are designed to protect the wires and cables in your home. There are special circuit breakers like GFCIs that are designed to keep you from being electrocuted, but let’s focus on normal circuit breakers.
The circuit breaker is designed to automatically shut off or trip if it detects too much electricity flowing through the circuit breaker. The more electricity that circulates, the more heat builds up along the wire. If you put too much electricity into a wire, it can get so hot that it will melt the plastic insulation covering the metal wire and ignite it.
I witnessed this at a friend’s house several years ago. Unknowingly, they plugged a heater that drew a lot of electricity into a wall outlet controlled by a dimmer. The dimmer has only been rated for 600 watts of electrical flow. The radiator consumed 1500 watts. Luckily my friend’s wife was in the room and saw smoke starting to come out of the wall switch.
The dimmer was seconds away from catching fire. They quickly went to the electrical panel and shut off that breaker, preventing a fire in the house. What would have happened if they had turned on the heating and went to a restaurant for breakfast or if they had gone to sleep?
If a circuit breaker in your home trips constantly, it is yelling to you that something is wrong. You may be drawing too much current. You need to bring in an electrician and find out what’s going on before you or your loved ones become a statistic.
You should use extreme caution when using extension cords. Visit the NFPA website and immerse yourself in all of the consumer education materials they offer. Familiarize yourself with how invisible electricity works in your home. Well worth the time.
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