Tripped circuit breakers are an issue that most of us have to deal with on occasion. You’ll know immediately when a circuit breaker trips. This is because it will cause you to instantly lose power to a certain room, part of your home or an appliance like your air conditioner. We’ll explain how to reset a circuit breaker when it trips and everything else you need to know about circuit breakers, how they work and what causes them to trip.

Understanding Why Circuit Breakers Trip

The purpose of circuit breakers is to prevent electrical fires and electrical damage, both of which can occur when a circuit gets overloaded. An overload is when the amperage of the electrical current flowing through a circuit spikes above what the circuit and the breaker are rated to handle. The reason that overloads are so dangerous is that, as the higher current flows through electrical wires, it causes them to get much hotter than they should. This can result in the insulation or sheathing around the wire melting, and the wires can also get so hot that they cause any nearby materials to catch fire.

Exactly how many watts of electricity you can draw from a single circuit is determined by both its amperage and voltage. The total amperage of an electrical current is calculated by dividing the voltage by the wattage draw. Amperage refers to the amount of electrical current flowing through a circuit whereas wattage is how much total power all devices on that circuit are currently drawing.

A 20-amp, 120-volt circuit could theoretically supply up to 2,400 watts at one time. However, circuit breakers are designed to trip when the current exceeds 80%-85% of its amperage rating. That means that the 20-amp breaker would typically trip if you tried to draw more than 1,920 to 2,040 watts at one time. This is the case since the increased wattage would exceed the breaker’s amperage threshold.

To simplify things, let’s say that you’re using a hair dryer, and then, someone else plugs in a vacuum to an outlet on the same 20-amp circuit. Hair dryers typically draw around 1,500 watts while vacuums are usually between 600 and 1,500 watts. Even if the vacuum was only 600 watts, turning it on would immediately trip the breaker. That would result in the wattage and thus the amperage rising above the breaker’s threshold.

This scenario where you’re trying to draw too many watts at one time is the most common reason a circuit breaker will trip. However, breakers can also trip as a result of a short circuit caused by a loose electrical connection or damaged wire. Either of these issues can allow the current to jump from the live wire across to the neutral wire.

This causes the current to essentially flow unimpeded, resulting in the amperage or current greatly increasing. Sometimes, appliances and electronic devices can also have issues that cause them to draw more power than they should, which also leads to the wattage and amperage spiking.

How to Reset a Tripped Circuit Breaker

Resetting a tripped circuit breaker is a simple task that only takes a few seconds. When you open the door on your electrical panel, you should easily be able to tell which circuit is tripped since it will be in the Off position. That means it will be flipped up to the left or right, depending on which side of the panel it’s located on. Most homes also have all of the breakers and circuits in the panel clearly labeled. That means you can just look for the name of the room or part of the house that lost power such as the bedrooms or kitchen.

Once you’ve identified the correct breaker, all that you have to do to reset it is flip it back down to where it latches into place. Most of the circuit breakers in your home you can just reset straight away. However, if your HVAC system trips the circuit breaker, you want to wait at least a few minutes before resetting the breaker. This is to allow the system to cool down, which helps to reduce the chances of it immediately tripping the breaker again.

If the breaker stays on and doesn’t trip again after you reset it, it usually indicates that either you were trying to draw too many watts or that there was a power surge. If it trips a second time, it’s likely that there is an electrical issue with the circuit or something that’s connected to it. In this situation, you’ll want to unplug everything from that circuit and then test each device one at a time by plugging it into a different circuit. This makes it easy to determine if one of the devices is faulty so that you then know to throw it away.

If none of the devices causes the other circuit to trip, you can be certain the issue lies with the wiring in the circuit or one of the outlets, light switches or hard-wired appliances connected to it. In this situation, you need to leave the breaker shut off until an electrician inspects the circuit and repairs whatever the issue is. If you try to keep using the circuit when it has any issues, you run the risk of starting an electrical fire.

An Overview of How Circuit Breakers Work

An electrical circuit is a loop, and power can only flow through it when the loop is intact or closed. When a circuit breaker trips, it breaks or opens the loop so that the current immediately stops flowing. Although there are a few different types of circuit breakers, they all function similarly. Inside the breaker is a stationary contactor and a moving contactor attached to an arm or lever. When the breaker is on and the loop is closed, the moving contactor is in an up position so that it directly touches the stationary contractor. This means the loop is closed so that the current flows from the moving contractor into the stationary contactor and then out into the rest of the circuit.

When the breaker trips, the lever that controls the moving contactor shifts downward. This instantly breaks the loop and stops the current from flowing since the two contactors now no longer touch. Resetting the breaker pushes the lever back up and locks the moving contactor into place to again close the loop and allow the power to flow.

Most circuit breakers detect current overloads using either an electromagnetic, a bi-metallic strip or, sometimes, both. With an electromagnet, the current overload creates a stronger electromagnetic force that causes the lever to trip and drop down. With a bi-metallic strip, the overload causes the strip to heat up and warp or bend, resulting in the lever tripping.

Your Trusted Professionals

If you’re experiencing any problems with a circuit breaker in your home or any other electrical issues, you can count on the experts at Accurate Home Services for help. We’ve been providing reliable electrical repair and installation services in the Kaufman and Crandall areas for more than 30 years. We’re also the company to turn to for your air conditioning and heating needs. Contact us today if you need an electrical inspection or to schedule any other service.

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