String Inverter Systems

What is a String Inverter?
A string inverter is a central unit that converts DC (direct current) from your solar panels to AC (alternating current) to power your appliances.

With string inverters, a group of panels (called a panel string) is wired together in series, with the end of the chain plugging into a string input on the inverter. Depending on the electrical characteristics of the equipment, string inverters can handle anywhere from 6-25 panels chained into a single inverter input.
Pros and Cons of String Inverters
Classic string inverters are the most cost-effective option if you can build your solar panels in full sunlight. If your system won’t be shaded by trees, buildings or other obstructions, a classic string inverter will save you some money without sacrificing performance.

If shade is a concern, you’ll likely want to add power optimizers to make the most of your system. Here’s why:

You’ve likely heard the saying, “a chain is only as strong as its weakest link.” That principle applies to panel strings. Because the panels are wired in series, if the output from one panel suffers, it will be mirrored across the whole string.

As a result, shade on a single panel can cause your array to produce well below its rated output. That problem is solved by adding power optimizers, which allow you to monitor and control the output of panels independently from each other.

Optimizers are only necessary if shade is a concern. If not, a classic string inverter will give you the most bang for your buck.
Learn More About String Inverters
Not sure if string inverters are the right choice for your system? Continue your research with these resources:

Review: SMA Sunny Boy string inverter
String inverters vs. Micro-inverters vs. Power Optimizers
Best grid-tie solar inverters
Solar Inverter Buying Guide