SMA sunny boy inverter is a solar inverter and uses renewable energy too. It is one of the most effective inverters you can buy. It stores surplus solar energy in the batteries which makes it reusable as needed. Hence, it is a safer option as compared to other inverters which do not use renewable sources of energy. There are many advantages of this inverter as well. However, there are some Sunny Boy inverter problems too which are displayed through sunny boy inverter fault codes. These fault codes have to be interpreted to understand what actually will be the solution for it. Read this article to know some common fault codes of sunny boy inverters and what they mean.

What are Sunny Boy Inverter Problems?

JAN 23 what are sunny boy inverter problems
Image from

Sunny Boy inverter is an inverter that uses renewable energy. It is manufactured by German inverter specialists SMA for the last 35 years. There are various models of this inverter available in the market. Any errors that arise in this machine are highlighted in the LCD display which is there in front of the chassis. Here are some problems that your inverter might face.

1. Your inverter might measure a grid voltage that is too high or too low in relation to the parameters that the inverter has been set to safely operate within.

2. It might happen that the inverter is no longer in grid parallel operation due to the fluctuation of frequency from an unstable grid connection and has stopped feed‑in operation for safety reasons.

3. Another problem is the huge proportion of direct current in the grid current. This is detected by the internal monitoring function of the SMA inverter.

4. Your SMA inverter is able to understand that there has been a mains failure (a power cut).

5. Your inverter is also able to recognize the missing protective earth connection from the AC supply side.

6. When the inverter starts to measure too much voltage from the panels, it usually indicates problems with the panels or with the inverter.

What are Sunny Boy Inverter Fault Codes?

Sunny boy inverter has specific fault codes for different events. Here, some important codes are mentioned with what they represent.

  • 102: Code 102 represents grid fault/grid overvoltage fast
  • 202: Code 202 represents grid fault/grid Undervoltage fast
  • 301: Code 301 represents grid fault/voltage increase protection
  • 501: Code 501 represents grid fault/grid frequency disturbance
  • 3401: Code 3401 represents DC overvoltage / overvoltage input A (SW) (3401)
  • 3501: Code 3501 represents insulation resistance/insulation failure (3501)
  • 6402: Code 6402 represents self-diagnosis/overtemperature (6402)
  • 6406: Code 6406 represents DC overcurrent/overcurrent input A (HW) (6406)
  • 7001: Code 7001 represents fault sensor interior temperature (7001)
  • 10221: Code 10221 represents new device cannot be administered

Also See: What are Enphase Micro Inverter Problems?

What are SMA Sunnyboy Inverter Faults and Repairs?

JAN 23 what are sunny boy inverter problemsAfter knowing about some sunny boy inverter problems, let’s look at some SMA Sunnyboy inverter faults and repairs.

1. Derating: Derating is the overheating in the inverter. This will require a replacement if the warranty period has ended, or a repair if within warranty.

2. Disturbance: Disturbance is a utility issue in the inverter. It pertains to an AC issue. This will need you to check the AC isolator below. Your inverter might need replacing.

3. Grid Monitoring: This message commonly appears during start-up and shutdown. But if it appears during midday, your inverter might need replacing.

4. Off-grid: This is a system islanding error. If your inverter shows this, then it needs to be replaced.

5. Riso: This fault pertains to insulation resistance. This will require a technician to attend to and test the panels and the balance of the system (BOS).

6. Waiting: This message usually occurs during the start-up and shutdown of the inverter. If it appears midday, you need to replace your inverter.

7. Varistor failure: It is indicative of a surge. This is a replaceable component of the inverter and needs to be replaced once it fails.

When Does Sunny Boy Inverter Stop Working?

Sunny Boy inverter will stop working when its mechanical requirements are not fulfilled. It will shut down in the following situations.

  • High/Low grid AC-voltage
  • High/Low grid frequency
  • Grid failure
  • Inverter Malfunction

Also Read: How to Fix Solar Lights Not Working?

How Can You Troubleshoot Your SMA Sunny Boy Inverter?

Your SMA Sunny Boy inverter might sometimes require troubleshooting for proper working. Read this pointer to know how you can power-cycle your sunny boy inverter.

Step 1: The first step of troubleshooting is turning off the DC disconnect. You can do this by turning the black dial on the underside of your inverter to the off position. Troubleshooting can be helpful when there are sunny boy inverter problems.

Step 2: You need to turn off the AC disconnect of your system. This is a lever, located next to the utility meter. You just have to pull it down into the off position.

Step 3: Wait for 5 minutes to switch them on. This step will go in reverse order. First, throw the AC lever back up into the on position. Then turn on the dial on the inverter.

After these steps, your inverter will take a few minutes to turn back on.

Also See: How to Connect Hybrid Inverter to Grid?

What are the Advantages of Sunny Boy Inverter?

Installing SMA sunny boy inverter can be useful as it has many perks apart from working with renewable energy.

  • Minimal installation costs are required for the Sunny Boy inverter.
  • There is no additional DC isolator required for the same.
  • It has a really great performance ratio along with affordable prices.
  • It gives a high efficiency of >93% even with low power input.
  • It gives IP65 protection for outdoor installation.
  • It has a long warranty period of 5 years, which can be extended to 15 years.
  • It has a wide operating temperature range from – 25º to + 60ºC ambient.

Also Read: 3 Amorphous Solar Panels Advantages and Disadvantages

How Long Does Sunny Boy Inverter Last?

Sunny boy inverter usually lasts between 5-12 years. This is because they have more electrical components which are sensitive to heat. However, some high-quality and well-maintained inverters could even last up to 20 years. Typically, the manufacturers of Sunny Boy inverters provide a warranty of about 5 to 10 years.

Now you know most of the sunny boy inverter problems and the ways to resolve them. With this information, you’ll be able to perfectly deal with SMA Sunnyboy inverter faults and repairs. However, if you are still not sure why your inverter is facing issues, it is always better to call a technician and get it resolved as soon as possible.

Recommended: Leasing Solar Panels vs Buying: What is Better?


Olivia is committed to green energy and works to help ensure our planet's long-term habitability. She takes part in environmental conservation by recycling and avoiding single-use plastic.

1 Comment

Leave A Reply