What Size Circuit Breakers Are Best for Solar Inverter?

Last Updated on July 11th, 2023

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When you think about a power circuit, more specifically a solar panel setup, what components come to mind?

The panels, of course, but what else; there are the wires and cables, then you have the controllers, inverters, and storage batteries, maybe even a wall monitor.

Did you consider any of the fail-safe technology that is needed to protect these solar electronic components from failure or being damaged by a power surge?

This is where circuit breakers come into play. Installed in between all the major components, these handy little gadgets will be able to break the circuit when surge hazards are present.

Which Sizes are There?

As for the size of the circuit breakers, the fuses needed will come in a variety of forms, many of which are engineered specifically for solar panel technology.

The size of the breaker will depend on the efficiency of the solar panels, the quality of cabling used, and the intensity of the sun in the location in which the solar panels are set up.

That being said, the larger commercialized and private solar farms will need larger circuit breakers. While homeowners will want to look into the same sizes, the smaller fuses will be for the water tank de-icers and street signs.

The standard sizes of these fuses are as follows:

Six amps
Eight amps
Ten amps
Fifteen amps
Twenty amps
Twenty-five amps
Thirty amps

Is There a Way to Calculate it?

There is a simple formula that comes with deciding what circuit breakers will be sufficient for the solar panel system to be installed.

But for the most part, anything that is used for residential or commercial usage will need to use circuit breakers from the size ranges above twenty-five amps.

The formula goes as such: Take the fuse size in amps, and equal that to the short circuit current in amps multiplied by one-point-five, six.

For instance, a twenty-four-volt, three-hundred-watt solar panel will normally have a rating of twenty-four volts and will have an optimal operating current between seven and eleven amps, while the short circuit current could get as high as twenty-two amps.

(22 (Amps)) x 1.56 = 34.32-amp fuse is needed)

Can You Still Use It If It Isn’t the Right Size?

Think about it in these terms, and when it comes to having a circuit breaker in place, it will need to be able to handle the highest surges.

That being said, if a unit is too small to handle the short circuit current peaks in power levels, then in effect, it will not be able to maintain the power flow without busting or constantly blowing out on you.

The larger-sized fuses are a different story. When these fuses pass current to the next device, they will allow too much power to the unit, which will cause failures in the system and for units to blow out as well.

Which Size is Common?

When you think about the systems and setups currently being used in the United States by businesses and homeowners, there is going to be a common thread of voltages that comes with being a part of the larger power grids.

For instance, the United States typically uses between one hundred and ten volts and one hundred and twenty voltages as a standard, while other countries will use closer to two hundred and twenty volts to two hundred and forty volts.

Each solar panel will need a thirty-amp circuit breaker, each connected in parallel, to prevent damages from occurring during normal operations.

Common Mistakes You Need to Avoid

First and foremost, using the wrong-sized circuit breakers – as mentioned above, having the wrong components can be catastrophic when it comes to regulating power levels.
Not having enough circuit breakers – the common saying goes, it is better to be safe than sorry, to which a business or homeowner will want to consult the installers and ensure both of you are on the same page.
Miscalculating amp ratings – Most certified electricians and solar panel experts will have monitoring tools and equipment that can accurately read the power flow levels of any solar panel system, hopefully preventing this mistake from happening.

Final Thoughts on What Size Circuit Breakers are Best for Solar Inverter

These systems are still relatively new to the market and constantly being revisited and improved, and innovations in these solar technologies are happening every day.

Even recently, when visiting an outdoor recreation outlet store, portable solar collection pieces of equipment were available for purchase.

Just remember to start simple. Even batteries are constantly being improved. Currently, most tech companies are racing to invent the most efficient, next-age power store batteries that can get you to another planet reliably.