Everything You Need to Know About Circuit Breaker Ratings
As a homeowner or electrical contractor, why are circuit breaker ratings important to you? Well, choosing a circuit breaker with the correct rating can be the difference between a safe installation and a dangerous one. While choosing the correct rating might seem complicated, don’t let it trip you up! In this blog, we’ll walk you through everything you need to know about breaker ratings to ensure your installation is as safe as possible.
Why Circuit Breaker Ratings Matter
Circuit breakers are essential for protecting people and properties. They automatically cut off the flow of electricity when they detect issues in the circuit, such as overloads or short circuits. For them to work effectively, circuit breakers must be correctly rated for the electrical load they are meant to support.
If the rating is too low, your breaker could overheat, causing melted wires, damage, or even a fire! On the flip side, if the rating is too high, the breaker might not trip when there's an overload, leaving your wires at risk of a fire. So, make sure to size your circuit breaker correctly to keep everything running safely and effectively.
Since using the wrong rating can have disastrous consequences, there are many local and national guidelines in place to standardize installations and keep everyone safe. For example, the National Electrical Code® 110.9 verifies that equipment designed to stop the flow of electricity must be rated appropriately for the current it’s meant to interrupt.
Amps & Volts in Circuit Breaker Ratings
To put it simply, a circuit breaker rating is a measurement of how much electricity it will allow to flow through a circuit before it trips and disconnects the power. This is generally measured in amps and volts. An amp is a measurement of electrical charge flowing through a wire, similar to measuring the flow of water through a pipe. Voltage measures the force of the electrons moving through a conductor, similar to the pressure of water running through a pipe.
A circuit breaker's maximum amperage rating measures how much continuous electrical current a breaker can handle without malfunctioning. If you’d like to determine the maximum amperage rating of a breaker, just look at the number printed on the operating handle, or “switch”.
Understand Amperage vs Interruption Circuit Breaker Ratings
Here’s a twist - you can have two different breakers with the same amperage rating and different interruption ratings. This is why it’s important to understand that the amperage rating only protects the conductors that are wired to the breaker, while the interruption rating protects the actual breaker and all downstream equipment.
The interrupting capacity for a specific circuit breaker is based on the combination of circuit configuration, current coil rating, maximum voltage rating, frequency, number of poles, and the appropriate regulatory agency requirements.
For example, a breaker with a 20-amp rating won’t trip unless that circuit exceeds 80% of that rating, or 16 amps. On the flip side, that same breaker might also have an interruption rating or ampere interrupting capacity (AIC) of 10,000 amps. This means that if the breaker is exposed to 10,000 amps or more, the breaker can safely stop the flow of the current without being damaged.
To identify the perfect circuit breaker rating for the job, you’ll need to determine the amperage and interruption rating that your power system will need to stay out of harm’s way. Once you access those details, the rest is simple. By choosing the right breaker rating, you can be proactive in your efforts to keep your electrical system safe and efficient.
Where can I find high-quality circuit breakers?
If you’re looking for tried and true circuit breakers available in a wide variety of ratings - you’ve come to the right place! At Big Electric Supply, we offer replacement breakers built to match the exact specifications of the original breakers used in a home’s panel board. Our circuit breakers are ETL-listed to the UL 489 molded case circuit breaker standard to ensure reliable performance. Plus, they're always newly manufactured- never refurbished or remanufactured. This guarantees durability and long-lasting value.
Time for new breakers? We Have You Covered
Our inventories are always well-stocked and prepared to meet your electrical needs. At Big Electric Supply, we have the parts you need to keep your electrical systems in mint condition. From major circuit breaker brands such as Square D, Eaton, and GE, to replacement breakers for old-school brands like Federal Pacific Breakers, Pushmatic Breakers, and Zinsco Breakers, we have plenty of electrical supplies to help you stay powered all year round.