Service Tip: How to change grid parameters for SMA inverters in Sunny Explorer

One of the most important steps during the commissioning process is connecting the inverter to the grid.  For the inverter to be suitable for the local grid, the correct country standards must be selected. However, in some areas, customized grid settings of the inverter need to be configured to meet the special requirements of the local utility grid. Wrong grid settings can cause inverters to frequently cut off or affect the stability of the local grid. SMA inverters have flexible grid settings which can easily be changed via Sunny Explorer. Your SMA inverter can easily meet the requirements from local grid providers and have a stable grid connection at the same time.

What is Sunny Explorer?

Sunny Explorer is a free software from SMA which enables local monitoring of SMA inverters via Bluetooth or Speedwire. With Sunny Explorer, you can easily monitor the performance of your inverter and detect any unusual behaviour.

With Sunny Explorer, the operating parameters of your inverter can easily be changed to meet any special requirements on-site. In a lot of countries or special areas, you will need to re-configure the grid parameters of your SMA inverter to meet the grid requirements. All that’s required is a Windows laptop which has Sunny Explorer installed. You can then use Sunny Explorer to connect your inverter via Bluetooth or Speedwire to change the grid parameters of your inverter.

SMA Grid Guard Code

To have a customized grid setting for your inverter, you will need to apply for a grid guard code from SMA before you visit the site. You can simply download the grid guard code via this link. Alternatively, the grid guard application form can also be found by searching “grid guard code “on the SMA website (http://www.sma.de/en/). Please fill in your details and send the form to ServiceLine@SMA.de.  SMA will provide you a grid guard code within 2 weeks after receiving the completed application form. Once you’ve received the grid guard code, simply input your grid guard code in the grid guard code section in Sunny Explorer. From there, you will be able to change the grid parameters in Sunny Explorer.

How to change the grid parameters in Sunny Explorer

Before you visit the site, please download Sunny Explorer on your Windows laptop. The program can be downloaded via this link. Please also make sure your laptop has Bluetooth as well, or alternatively a Speedwire cable can be used to connect directly to the inverter’s Webconnect.

1. Login to Sunny Explorer as an installer. Simple instructions on how to do so can be found in the Tech Tip video, ‘Tech Tip: Connecting Bluetooth® to SMA Inverters.’ (Default Password for installer is 1111). Watch the video here>>
2. When you are on the page of Sunny Explorer, click “Option“- “Grid guard code” on the top side of the window to enter your grid guard code. Then navigate to the “Grid Monitoring” settings. Under the “Grid monitoring” setting, please adjust the grid parameters (Grid voltage, Frequency, tripping time etc.) according to the requirements from the grid provider. Please make sure to save the settings before exiting.

Examples adjusting grid parameters using Sunny Explorer

Below are some examples of how to use Sunny Explorer to adjust the grid parameters of the inverter to meet the requirements from a local grid provider.

Example 1:

Two-stage overvoltage tripping requirements (similar to what is required by Ergon Energy)

Vnom-max = 255V (10 minute rolling average)

Overvoltage 1 = 260V, trip time < 2 seconds

Overvoltage 2 = 265V, trip time < 0.2 seconds

The following adjustments need to be made in Sunny Explorer to meet the requirements:

Example 2: 

Modified Frequency Limit trip points (similar to what is required by Ausgrid for >30kVA installs)

Frequency upper limit = 52hz, trip time < 2 seconds

Frequency lower limit = 47hz, trip time < 2 seconds

The following adjustments need to be made in Sunny Explorer to meet the requirements:

Example 3

Implement a Power-Voltage response curve (similar to what is required by Western Power for >30kVA installs)

The following response curve from AS/NZS4777.2:2015 needs to be implemented:

Example of a Power Voltage Response Curve

The following adjustments need to be made in Sunny Explorer to meet the requirements:

Step 1:

Step 2:

Conclusion

A clear understanding about the requirements from the grid provider is the first and most important step in the inverter grid connection process. With the flexible grid setting of SMA inverters in Sunny Explorer, customers and installers can easily adjust the relevant grid parameters of the inverters to meet the requirements from the grid provider. Correct grid settings of the inverters will help the system avoid cut-offs due to grid voltage and frequency issues and guarantee a stable performance of your solar system.