String inverters, also known as central inverters, have been a reliable and cost-effective solution for small-scale solar installations for decades. The inverter takes the direct current from each solar panel and converts it into alternating current. The maximum number of solar panels that can be connected to a string inverter is determined by the input voltage rating of the inverter. String inverters are most suitable for rooftops that have a consistent southern orientation and are free from any shading problems.
The solar array, consisting of a string of solar panels, is connected to a string inverter. There are numerous methods for connecting a string of solar panels together. A typical solar array may include approximately 15 solar panels, with each panel having a capacity of 250Wp.
Advantages of String Inverters
The major advantages are:
1. Cost Effective
Currently, string inverters are more cost-effective compared to micro inverters. For each installation, you only need a single-string inverter, whereas, for micro inverters, you would require one inverter for each panel.
2. Easy to Maintain and Troubleshoot
The majority of string inverters are typically installed in a central location, securely mounted on the wall. This simplifies maintenance efforts by eliminating the need to constantly travel back and forth to the field for troubleshooting purposes. In places with freezing or hot climates, this is beneficial on the inverter’s end.
3. Trusted Technology
String inverters have been used for many years and are easily understood by electricians. People have confidence in its technology and reliability.
Disadvantages of String Inverters
Even though inverters have been around for a long time, they have some noticeable drawbacks.
If the size of the string inverter is too big, you won’t be able to expand it later on. Once you install it for a specific power rating, you can’t change the rating of the inverter. You need to buy another inverter in such a situation.
2. Point of Failure
If the inverter malfunctions, the entire solar array will become non-functional. The potential impact of this could result in a substantial decrease in electricity generation.