SMA Sunnyboy Solar Inverter Faults and Repairs

German solar inverter specialists SMA have been a leading manufacturer in renewable energy technologies for the last 35 years. SMA SunnyBoy solar inverters come in a range of colours including red, blue and yellow. SMA Sunnyboy solar inverters have been widely installed in the UK, some of the most popular being the SB1200, SB2000 and SB3000. High frequency models include the SB2000HF, SB2500HF, and SB3000HF. Transformerless models include the SB3000TL and the SB3600TL.

We have installed SMA equipment for our own clients for many years and we also have a lot of experience in working with their equipment for new clients on the support side. So if you would like help with diagnosing faults, carrying out servicing or repairs and or are currently without an installer then you will find us well qualified and pleased to help.

SMA Tripower (three phase) faults and repairs

All Solar Inverter Fault Codes, Warnings and Troubleshooting

Solar PV System Repairs

Solar Inverter Replacement

SMA SunnyBoy solar inverters have LCD displays on the front of the chassis, which providing it's working, will highlight any errors with the solar inverter or the solar PV system that it runs, some will show event numbers, others just a message. We have listed and described common faults with SMA SunnyBoy solar inverters and what action to take to resolve them below:

TL Series

SMA SunnyBoy Solar Inverter Faults and Warnings:

Some of the advice we give related to identifying, confirming and or resolving some of the faults detailed below, starts with safely shutting down and restarting the solar inverter and the solar PV system. This is something that nearly all solar PV systems installed in the UK would have been designed to be carried out safely by the solar PV system owner. However, paperwork, schematics and manuals are not always clear or available, so if you have any concerns about how to do this, Contact us and we will be pleased to talk you through the process over the telephone at no charge.

How to Restart a SMA SunnyBoy Solar Inverter:

HF Series

Restart SMA SunnyBoy Solar Inverter
AC Isolator

Leave everything near the supply meters turned on. At the solar inverter there will be an AC isolator, this is used to isolate the mains/grid supply from the solar inverter and to prevent the solar inverter from feeding solar power into the electrical system. Switch the AC isolator 'off', if the solar inverter is running correctly you will hear a clunk inside the machine and after a while a 'grid fault', 'missing grid' warning or similar will appear on the LCD display.

Near to the solar inverter might be a method of isolating the solar (DC) supply from the solar inverter. Often these are black and grey and will be labelled 'DC isolator' or similar. There might be two or more of these if the system is fed by multiple strings.

All SunnyBoy solar inverters have a built in ESS switch / DC isolator. The TL Series and the older SunnyBoys have a handsized black plastic component on the underside of the chassis. Getting a good grip on this, pulling this straight down will isolate the DC circuits. The HF Series of SunnyBoy solar inverters have a black plastic piece that runs across the bottom of the solar inverter. You will find a hand grip in the centre, pulling this straight down will release the whole lower part of the solar inverter (the black plastic part) and isolate the DC circuits. More modern SMA SunnyBoy solar inverters have a rotary style on/off switch to isolate the DC circuits mounted on the left hand side of the chassis.

When all of the lights on the solar inverter have gone out, reintroduce the AC/mains power supply by turning the AC isolator 'on'. Introduce the DC supply by reinserting the ESS switch (push straight up) and turn any external DC isolators 'on'.

This will restart the solar inverter, on the display it will show you progress during it's startup procedure. During startup is when the solar inverter carries out all of the tests needed before being able to connect the solar supply to the electrical system. If errors are found during testing they will be displayed on the screen or an indication light might come on. Make a note of any warning messages, warning lights and fault codes.

If the restart is succesful a green light will come on, sometimes flashing at first but once connected to the mains/AC supply, remaining permenantly on. The LCD display will show how much power the solar PV system is generating. The solar PV system can be verified as working at the solar generation / Feed in Tariff (FIT) meter which will count on the display, the red light will pulse as it counts.

SMA SunnyBoy Solar Inverter: No lights, No Display

SMA SunnyBoy solar inverters are powered by the solar panels (the DC supply) and will startup at sunrise each day and shutdown at night. If you find the solar inverter with no lights or display working during the day, there is either a problem with the solar panels or with the solar inverter. Follow the shutdown and restart procedure outlined above and if the problem persists Contact us to discuss the next steps.

If you have the correct tools and are comfortable in doing so, isolate the AC and DC power supplies from the solar inverter and confirm that the incoming DC voltages are as expected by measuring between the positive and negative incoming terminals in DC isolators (if avalable) and or at the DC solar inverter inputs. Light conditions and the type of solar panel will affect voltages but as a rule of thumb anywhere from 30V-60V per panel x the number of panels connected in series in the string would be a reasonable voltage estimate.

No or very low DC voltage would suggest a problem with the solar panels, measuring the expected voltage at the isolator terminals and or the DC inputs, although additional testing should be carried out, would suggest a problem with the solar inverter. Contact us to discuss the next steps.

SMA Sunnyboy Solar Inverter Fault Codes and Explanations:

SunnyBoy

* Event 1 - Grid Fault - The solar inverter is measuring a grid (mains) voltage or a grid impedence that is too high in relation to the parameters that the solar inverter has been set to safely operate within. See * Event 8 - Grid Fault below. If this fault persists contact us to arrange for a solar engineer to visit to establish whether the fault lies with the solar inverter or with the grid.

* Event 2 - Grid Fault - The solar inverter is measuring a grid (mains) voltage or a grid impedence that is too low in relation to the parameters that the solar inverter has been set to safely operate within. If this fault persists and mains power is available to other local circuits then check that all isolators, MCBs and RCDs on the AC side of the solar PV system are 'On' and carry out the procedures outlined for * Event 8 - Grid Fault below. If everything on the grid/mains power supply side including the solar generation meter is switched 'on', this would be an indication that there is either an internal fault within the solar inverter or there's a problem with the grid/mains power supply. Contact us to arrange for a solar engineer to visit to establish whether the fault lies with the solar inverter or with the grid/mains power supply.

* Event 3 - Grid Fault - The solar inverter has measured a 10 minute average grid (mains) voltage or a grid impedence that is too high in relation to the parameters that the solar inverter has been set to safely operate within. See * Event 8 - Grid Fault below. If this fault persists contact us to arrange for a solar engineer to visit to establish whether the fault lies with the solar inverter or with the grid.

* Event 4 - Grid Fault - The solar inverter is no longer in grid parallel operation due to frequency fluctations from an unstable grid (mains) connection and has stopped feed‑in operation for safety reasons. See * Event 8 - Grid Fault below. If this fault persists contact us to arrange for a solar engineer to visit to establish whether the fault lies with the solar inverter or with the grid.

* Event 5 - Grid Fault - The solar inverter is measuring a grid (mains) frequency that is either too high or too low in relation to the parameters that the solar inverter has been set to safely operate within. See * Event 8 - Grid Fault below. If this fault persists contact us to arrange for a solar engineer to visit to establish whether the fault lies with the solar inverter or with the grid.

* Event 6 - Grid Fault - The internal monitoring function of the solar inverter has detected an excessively high proportion of direct current in the grid current. See * Event 8 - Grid Fault and * Event 35 - Insulation resist below. If this fault persists contact us to arrange for a solar engineer to visit to establish whether the fault lies with the solar panels, the solar inverter or with the grid.

* Event 7 - Frq. not permitted - The solar inverter is measuring a power frequency outside the permissible range that the solar inverter has been set to safely operate within. See * Event 8 - Grid Fault below. If this fault persists contact us to arrange for a solar engineer to visit to establish whether the fault lies with the solar inverter or with the grid.

* Event 8 - Waiting for grid voltage - Grid Failure - Check Fuse - The solar inverter understands that there has been a mains failure (a power cut). If this fault persists and mains power is available to other local circuits then check that all isolators, MCBs and RCDs on the AC side of the solar PV system are 'On'.

Check fuses, isolators, Miniture Circuit Breakers (MCBs) and Residual Current Devices (RCDs) in and around consumer units, around the solar generation and mains/grid supply meters and see if anything marked 'solar PV' or you can see is related to the solar PV system is switched 'off'. The solar generation meter draws it's power from the mains so if this isn't on, this would be a strong indication that something heading toward the incoming grid/mains power supply has tripped off.

RCD

MCB

An RCD has a test button and is twice the width or a circuit breaker. An RCD that's switched itself 'off' is an indication that it has picked up an earth fault somewhere on the circuit that it protects, this fault could be anywhere on the circuit and might have been temporary.

- If an RCD has switched itself 'off' it's ok to try to turn it back 'on' again. If you meet with instant and strong resistance to closing the switch, leave it 'off'. If it stays on for a short while and switches off when the solar PV system has warmed up and begun to feed in power, there's most likely a problem with the solar PV system somewhere, leave the RCD turned 'off' and contact us to discuss the next steps.

If the RCD remains on for a few hours, weeks or days and then switches itself off, faults like these are often weather related. Damp cables and wet or windy conditions will often expose faults both physical and in design, with AC and DC cabling, connectors, solar panels and RCDs. Contact us to discuss the next steps.

If the RCD stays on, the solar inverter starts up and everything works fine in all conditions - all good.

- If a circuit breaker has switched 'off' this is an indication of either a short circuit, most likely a serious failure either within the solar inverter or with the solar inverter supply cable. Or for some other reason the circuit breaker has picked up a fault and isolated the circuit to prevent the solar inverter supply cable from becoming overloaded.

Turn on circuit breakers at your own risk, there is the potential to cause damage and only do so when you are able to access and inspect the solar inverter and all isolation equipment whilst it's in operation. If you meet instant and strong resistance, leave the circuit breaker 'off' and turn everything to do with the solar PV system 'off' remembering to also safely isolate the DC circuits.

If the circuit breakers stays on and then switches itself off after a few minutes, this is reasonably strong indication that the solar inverter has a serious internal fault. Turn off everything to do with the solar PV system including the DC isolators and contact us to discuss the next steps.

* Event 9 - PE conn. missing - Check connection - The solar inverter understands that the protective earth connection is missing from the AC supply side. If this fault persists and mains power is available to other local circuits then check that all isolators, MCBs and RCDs on the AC side of the solar PV system are 'On'. If automatic safety devices such as MCBs or RCDs have switched 'Off' then leave them 'Off' and contact us to arrange for a solar engineer to visit to establish whether the fault lies with the solar inverter or the supply circuit.

* Event 10 - L / N swapped - Check connection - The solar inverter understands that the Live and Neutral connectors are swapped on the AC supply side. This fault is unlikely to occur in an existing installation that has previously worked correctly. If this fault persists contact us to arrange for a solar engineer to visit to establish whether the fault lies with the solar inverter or the supply circuit.

* Event 11 - Installation fault - Check connection - The solar inverter understands that either the Live and Neutral connectors are swapped on the AC supply side or the second phase has been connected to the Neutral on a three phase circuit. This fault is unlikely to occur in an existing installation that has previously worked correctly. If this fault persists contact us to arrange for a solar engineer to visit to establish whether the fault lies with the solar inverter or the supply circuit.

* Event 33 - Unstable operation - The solar inverter is measuring low DC voltage. Assuming that there is adequate sunlight, this is an existing installation that has been specified correctly, no changes near the installation area have been carried out and the system has operated before without problems, if this error persists then we would advise that the DC side of the system including and excluding the solar inverter is tested.

* Event 34 - DC overvoltage - Disconnect generator - The solar inverter is measuring too much voltage from the solar panels. Assuming that this is an existing installation that has been specified correctly, hasn't recently been changed or added to and has operated before without problems. This could mean either a problem with the solar panels or with the solar inverter. We would advise that the DC side of the system is disconnected using either the built in DC isolator at the bottom of the solar inverter or the DC Isolator installed between the solar panels and the solar inverter (if available) and contact us to test the DC side of the system including and excluding the solar inverter.

* Event 35 - Insulation resist - Check generator - This error is generated when during normal operation of the solar inverter, a leakage current to ground/earth is detected on the DC side of the system. Although it is also possible that the solar inverter generates this alarm message due to AC leakage currents connected to the capacitive nature of the solar panels compared to ground/earth or there could be a problem with the solar inverter itself.

For as long as the situation persits then the solar inverter will not startup. Earth / Ground Faults (also called Insulation or Isolation Faults) often present themselves when it is raining or at times of high humidity when moisture can enter the solar PV system through damaged solar panels, connectors or cabling. These faults often clear when weather conditions improve but they will not get better by themselves, most often degrading and becoming more dangerous over time.

We would advise that you book a solar repair engineer's visit in order to carry out a full solar system test, identify the source and rectify the fault. We've written more about how to identify and repair ground faults here: Ground Faults, Isolation (ISO) Faults, RISO Low Faults and Insulation Resistance Faults with Solar PV Systems

* Event 36 - High discharge curr. - Check generator - This error is generated when during normal operation of the solar inverter, a leakage current to ground/earth is detected on the DC side of the system. See Event 35 - Insulation resist above. We would advise that you book a solar repair engineers visit in order to carry out a full system test, identify the source and rectify the fault.

* Event 37 - Resid.curr.too.high - Check generator - This error is generated when during normal operation of the solar inverter, a leakage current to ground/earth is detected on the DC side of the system. See Event 35 - Insulation resist above. We would advise that you book a solar repair engineers visit in order to carry out a full system test, identify the source and rectify the fault.

* Event 38 - DC overcurrent - Check generator - The solar inverter is measuring too much current from the solar panels. Assuming that this is an existing installation that has been specified correctly, hasn't recently been changed or added to and has operated before without problems. This could mean either a problem with the solar panels or with the solar inverter. We would advise that the DC side of the system is disconnected using either the built in DC isolator at the bottom of the solar inverter or the DC Isolator installed between the solar panels and the solar inverter (if available) and contact us to test the DC side of the system including and excluding the solar inverter.

* Event 39 - Waiting for DC start conditions - Start cond. not met - The solar inverter is measuring low DC voltage. Assuming that there is adequate sunlight, this is an existing installation that has been specified correctly, no changes near the installation area have been carried out and the system has operated before without problems, then if this fault persists, we would advise that the DC side of the system including and excluding the solar inverter is tested.

* Event 60 - Self diagnosis - Interference device - If after the system has been safely shutdown and restarted this condition persists the inverter has a fatal error and should be replaced. There are a few ways that we can help with this: Solar Inverter Replacement

* Event 61 - Self diagnosis - Interference device - If after the system has been safely shutdown and restarted this condition persists the inverter has a fatal error and should be replaced. There are a few ways that we can help with this: Solar Inverter Replacement

* Event 62 - Self diagnosis - Interference device - If after the system has been safely shutdown and restarted this condition persists the inverter has a fatal error and should be replaced. There are a few ways that we can help with this: Solar Inverter Replacement

* Event 63 - Self diagnosis - Interference device - If after the system has been safely shutdown and restarted this condition persists the inverter has a fatal error and should be replaced. There are a few ways that we can help with this: Solar Inverter Replacement

* Event 64 - Self diagnosis - Interference device - If after the system has been safely shutdown and restarted this condition persists the inverter has a fatal error and should be replaced. There are a few ways that we can help with this: Solar Inverter Replacement

* Event 65 - Self diagnosis - Overtemperature - The ambient temperature around the solar inverter is too hot. This could be due to a number of factors, for example 1) If the solar inverter is exposed to direct sunlight 2) If the solar inverter has been installed without adequate ventilation around the chassis which would allow excess heat to dissipate 3) The solar inverter's components are getting too hot due to an internal component fault. If the unit isn't running hot and if after the system has been safely shutdown and restarted this condition persists then contact us.

* Event 66 - Self diagnosis - Overload - If after the system has been safely shutdown and restarted this condition persists the inverter has a fatal error and should be replaced. There are a few ways that we can help with this: Solar Inverter Replacement

* Event 67 - Comm. disturbed - If after the system has been safely shutdown and restarted this condition persists the inverter has a fatal error and should be replaced. There are a few ways that we can help with this: Solar Inverter Replacement

* Event 68 - Self diagnosis - Input A defective - If after the system has been safely shutdown and restarted this condition persists the inverter has a fatal error and should be replaced. There are a few ways that we can help with this: Solar Inverter Replacement

* Event 69 - Self diagnosis - Input B defective - If after the system has been safely shutdown and restarted this condition persists the inverter has a fatal error and should be replaced. There are a few ways that we can help with this: Solar Inverter Replacement

* Event 70 - Sensor fault fan permanently on - If after the system has been safely shutdown and restarted this condition persists the inverter has a fatal error and should be replaced. There are a few ways that we can help with this: Solar Inverter Replacement

* Event 71 - Various messages - There are various messages that can be present alongside an Event 71 fault code. These are mostly related to the SD card and firmware. Contact us with the exact message as displayed on the screen to discuss what these issues might be and how they can be resolved.

* Event 72 - Data stor. not poss. - If after the system has been safely shutdown and restarted this condition persists the inverter has a fatal error and should be replaced. There are a few ways that we can help with this: Solar Inverter Replacement

* Event 73 - Various messages - There are various messages that can be present alongside an Event 73 fault code. These are mostly related to internal components that are showing errors but the errors aren't serious enough to preEvent grid feed in. Contact us with the exact message as displayed on the screen to discuss what these issues might be and how they can be resolved.

* Event 74 - Varistor defective - If after the system has been safely shutdown and restarted this condition persists the inverter has a fatal error and should be replaced. There are a few ways that we can help with this: Solar Inverter Replacement

* Event 75 - Fan fault - Clean fan - The temperature inside the solar inverter is too hot which the solar inverter understands is due to dust, fluff or a similar obstruction blocking the vents or fans inside the chassis. If after the system has been safely shutdown and restarted this condition persists then contact us.

* Event 77 - Self diagnosis - Interference device - If after the system has been safely shutdown and restarted this condition persists the inverter has a fatal error and should be replaced. There are a few ways that we can help with this: Solar Inverter Replacement

* Event 80 - Derating occurred - The solar inverter has measuring a temperature for more than 10 minutes that is too hot and has reduced power output to protect itself. This could be due to a number of factors, for example 1) If the solar inverter is exposed to direct sunlight 2) If the solar inverter has been installed without adequate ventilation around the chassis which would allow excess heat to dissipate 3) The solar inverter's components are getting too hot due to an internal component fault. If the unit isn't running hot and if after the system has been safely shutdown and restarted this condition persists then contact us.

* Event 81 - Comm. disturbed - If after the system has been safely shutdown and restarted this condition persists the inverter has a fatal error and should be replaced. There are a few ways that we can help with this: Solar Inverter Replacement

* Event 90 - Various messages - There are various messages that can be present alongside an Event 90 fault code. These are mostly related to the initial setup at installation so should not be present on an existing system. If after the system has been safely shutdown and restarted this condition persists then contact us us with the exact message as displayed on the screen to discuss what these issues might be and how they can be resolved.

SMA SunnyBoy TL Series Inverter Event Codes

* Events 101, 102, 103 - Grid Fault - The solar inverter is measuring a grid (mains) voltage or a grid impedence that is too high in relation to the parameters that the solar inverter has been set to safely operate within. See * Event 801 - Waiting for grid voltage below. If this fault persists contact us to arrange for a solar engineer to visit to establish whether the fault lies with the solar inverter or with the grid.

* Events 202, 203, 205 - Grid Fault - The solar inverter is measuring a grid (mains) voltage or a grid impedence that is too low in relation to the parameters that the solar inverter has been set to safely operate within. If this fault persists and mains power is available to other local circuits then check that all isolators, MCBs and RCDs on the AC side of the solar PV system are 'On'. See * Event 801 - Waiting for grid voltage below.

* Event 301 - Grid Fault - The solar inverter has measured a 10 minute average grid (mains) voltage or a grid impedence that is too high in relation to the parameters that the solar inverter has been set to safely operate within. See * Event 801 - Waiting for grid voltage below. If this fault persists contact us to arrange for a solar engineer to visit to establish whether the fault lies with the solar inverter or with the grid.

* Event 401 - Grid Fault - The solar inverter is no longer in grid parallel operation due to frequency fluctations from an unstable grid (mains) connection and has stopped feed‑in operation for safety reasons. See * Event 801 - Waiting for grid voltage below. If this fault persists contact us to arrange for a solar engineer to visit to establish whether the fault lies with the solar inverter or with the grid.

* Event 501 - Grid Fault - The solar inverter is measuring a grid (mains) frequency that is either too high or too low in relation to the parameters that the solar inverter has been set to safely operate within. See * Event 801 - Waiting for grid voltage below. If this fault persists contact us to arrange for a solar engineer to visit to establish whether the fault lies with the solar inverter or with the grid.

* Event 601 - Grid Fault - The internal monitoring function of the solar inverter has detected an excessively high proportion of direct current in the grid current. See * Event 801 - Grid Fault and * Event 3501 - Insulation failure below.If this fault persists contact us to arrange for a solar engineer to visit to establish whether the fault lies with the solar panels, the solar inverter or with the grid.

* Event 701 - Frq. not permitted, Check Parameter - The solar inverter is measuring a power frequency outside the permissible range that the solar inverter has been set to safely operate within. See * Event 801 - Waiting for grid voltage below. If this fault persists contact us to arrange for a solar engineer to visit to establish whether the fault lies with the solar inverter or with the grid.

* Event 801 - Waiting for grid voltage - Grid Failure - Check AC Circuit Beaker - The solar inverter understands that there has been a mains failure (a power cut). If this fault persists and mains power is available to other local circuits then check that all isolators, MCBs and RCDs on the AC side of the solar PV system are 'On'.

RCD

MCB

If the RCD stays on, the solar inverter starts up and everything works fine in all conditions - all good.

If the circuit breaker stays on, the solar PV inverter starts up and feeds power into the electrical system through the circuit breaker; although the circuit breaker will continue to protect the circuit, ideally a physical inspection and electrical test of the supply circuit including all isolators, circuit breakers, RCDs and electrical connections would also be carried out.

- Everything's 'on' but the error remains and the solar inverter won't start. If everything on the grid/mains power supply side including the solar generation meter is switched 'on', this would be an indication that there is either an internal fault within the solar inverter or there's a problem with the grid/mains power supply. Contact us to discuss the next steps.

* Event 901 - PE conn. missing - Check connection - The solar inverter understands that the protective earth connection is missing from the AC supply side. If this fault persists and mains power is available to other local circuits then check that all isolators, MCBs and RCDs on the AC side of the solar PV system are 'On'. If automatic safety devices such as MCBs or RCDs have switched 'Off' then leave them 'Off' and contact us to arrange for a solar engineer to visit to establish whether the fault lies with the solar inverter or the supply circuit.

* Event 1001 - L / N swapped - Check connection - The solar inverter understands that the Live and Neutral connectors are swapped on the AC supply side. This fault is unlikely to occur in an existing installation that has previously worked correctly. If this fault persists contact us to arrange for a solar engineer to visit to establish whether the fault lies with the solar inverter or the supply circuit.

* Event 1501 - Reconnection fault grid - - This Event code is related to the initial setup when the country code and grid connection parameters are set and should not be present on an existing system that has peviously worked without issue. If after the system has been safely shutdown and restarted this condition persists then contact us to discuss the next steps.

* Events 3301, 3302, 3303 - Unstable operation - The solar inverter has measured a 10 minute average grid (mains) voltage or a grid impedence that is too high in relation to the parameters that the solar inverter has been set to safely operate within. If this fault persists contact us to arrange for a solar engineer to visit to establish whether the fault lies with the solar inverter or with the grid.

* Event 3304 - Gen. output too low - The solar inverter is measuring low DC voltage. Assuming that there is adequate sunlight, this is an existing installation that has been specified correctly, no changes near the installation area have been carried out and the system has operated before without problems, if this error persists then we would advise that the DC side of the system including and excluding the solar inverter is tested.

* Events 3401, 3402 - DC overvoltage - Disconnect generator - The solar inverter is measuring too much voltage from the solar panels. Assuming that this is an existing installation that has been specified correctly, hasn't recently been changed or added to and has operated before without problems. This could mean either a problem with the solar panels or with the solar inverter. We would advise that the DC side of the system is disconnected using either the built in DC isolator at the bottom of the solar inverter or the DC Isolator installed between the solar panels and the solar inverter (if available) and contact us to test the DC side of the system including and excluding the solar inverter.

* Event 3501 - Insulation failure - Check generator - This error is generated when during normal operation of the solar inverter, a leakage current to ground/earth is detected on the DC side of the system. Although it is also possible that the solar inverter generates this alarm message due to AC leakage currents connected to the capacitive nature of the solar panels compared to ground/earth or there could be a problem with the solar inverter itself.

* Event 3601 - High discharge curr. - Check generator - This error is generated when during normal operation of the solar inverter, a leakage current to ground/earth is detected on the DC side of the system. See Event 3501 - Insulation Failure - Check generator above. We would advise that you book a solar repair engineers visit in order to carry out a full system test, identify the source and rectify the fault.

* Event 3701 - Resid.curr.too.high - Check generator - This error is generated when during normal operation of the solar inverter, a leakage current to ground/earth is detected on the DC side of the system. See Event 3501 - Insulation Failure - Check generator above. We would advise that you book a solar repair engineers visit in order to carry out a full system test, identify the source and rectify the fault.

* Events 3801, 3802 - DC overcurrent - Check generator - The solar inverter is measuring too much current from the solar panels. Assuming that this is an existing installation that has been specified correctly, hasn't recently been changed or added to and has operated before without problems. This could mean either a problem with the solar panels or with the solar inverter. We would advise that the DC side of the system is disconnected using either the built in DC isolator at the bottom of the solar inverter or the DC Isolator installed between the solar panels and the solar inverter (if available) and contact us to test the DC side of the system including and excluding the solar inverter.

* Events 3901, 3902 - Waiting for DC start conditions - Start cond. not met - The solar inverter is measuring low DC voltage. Assuming that there is adequate sunlight, this is an existing installation that has been specified correctly, no changes near the installation area have been carried out and the system has operated before without problems, then if this fault persists, we would advise that the DC side of the system including and excluding the solar inverter is tested.

* Events 6001 - 6438 - Self diagnosis - Interference device - If after the system has been safely shutdown and restarted this condition persists the inverter has a fatal error and should be replaced. There are a few ways that we can help with this: Solar Inverter Replacement

* Events 6501, 6502 - Self diagnosis - Overtemperature - The ambient temperature around the solar inverter is too hot. This could be due to a number of factors, for example 1) If the solar inverter is exposed to direct sunlight 2) If the solar inverter has been installed without adequate ventilation around the chassis which would allow excess heat to dissipate 3) The solar inverter's components are getting too hot due to an internal component fault. If the unit isn't running hot and if after the system has been safely shutdown and restarted this condition persists then contact us.

* Event 7008 - Disturbance sensor display temperature - If after the system has been safely shutdown and restarted this condition persists the inverter has a fatal error and should be replaced. There are a few ways that we can help with this: Solar Inverter Replacement

* Event 7101 - SD card defective - If after the system has been safely shutdown and restarted this condition persists the inverter has a fatal error and should be replaced. There are a few ways that we can help with this: Solar Inverter Replacement

* Event 7102 - Parameter file not found or defective - If after the system has been safely shutdown and restarted this condition persists the inverter has a fatal error and should be replaced. There are a few ways that we can help with this: Solar Inverter Replacement

* Event 7105 - Param. setting failed - If after the system has been safely shutdown and restarted this condition persists the inverter has a fatal error and should be replaced. There are a few ways that we can help with this: Solar Inverter Replacement

* Event 7106 - Update file defect. - If after the system has been safely shutdown and restarted this condition persists the inverter has a fatal error and should be replaced. There are a few ways that we can help with this: Solar Inverter Replacement

* Event 7110 - No update file found - If after the system has been safely shutdown and restarted this condition persists the inverter has a fatal error and should be replaced. There are a few ways that we can help with this: Solar Inverter Replacement

* Events 7201, 7202 - Data stor. not poss. - If after the system has been safely shutdown and restarted this condition persists the inverter has a fatal error and should be replaced. There are a few ways that we can help with this: Solar Inverter Replacement

* Event 7303 - Update main CPU failed - If after the system has been safely shutdown and restarted this condition persists the inverter has a fatal error and should be replaced. There are a few ways that we can help with this: Solar Inverter Replacement

* Event 7305 - Update RS485I module failed - If after the system has been safely shutdown and restarted this condition persists the inverter has a fatal error and should be replaced. There are a few ways that we can help with this: Solar Inverter Replacement

* Event 7307 - Update BT failed - If after the system has been safely shutdown and restarted this condition persists the inverter has a fatal error and should be replaced. There are a few ways that we can help with this: Solar Inverter Replacement

* Event 7311 - Update language table failed - If after the system has been safely shutdown and restarted this condition persists the inverter has a fatal error and should be replaced. There are a few ways that we can help with this: Solar Inverter Replacement

* Event 7401 - Varistor defective - If after the system has been safely shutdown and restarted this condition persists the inverter has a fatal error and should be replaced. There are a few ways that we can help with this: Solar Inverter Replacement

* Event 7508 - External fan fault - The temperature inside the solar inverter is too hot which the solar inverter understands is due to dust, fluff or a similar obstruction blocking the vents or fans inside the chassis. If after the system has been safely shutdown and restarted this condition persists then contact us.

* Event 8001 - Derating occurred - The solar inverter has measuring a temperature for more than 10 minutes that is too hot and has reduced power output to protect itself. This could be due to a number of factors, for example 1) If the solar inverter is exposed to direct sunlight 2) If the solar inverter has been installed without adequate ventilation around the chassis which would allow excess heat to dissipate 3) The solar inverter's components are getting too hot due to an internal component fault. If the unit isn't running hot and if after the system has been safely shutdown and restarted this condition persists then contact us.

* Events 8801, 8802, 8803 - No display - If after the system has been safely shutdown and restarted this condition persists the inverter has a fatal error and should be replaced. There are a few ways that we can help with this: Solar Inverter Replacement

* Event 9002, 9003, 9005 - Various messages - There are various messages that can be present alongside Event 9000 event codes. These are mostly related to the initial setup at installation so should not be present on an existing system. If after the system has been safely shutdown and restarted this condition persists then contact us us with the exact message as displayed on the screen to discuss what these issues might be and how they can be resolved.

Solar PV System Repairs

Solar Inverter Replacement

SMA Sunnyboy Inverter Manuals:

SunnyBoy 1100, 1200, 1700 Installation Manual	SunnyBoy 1200, 1700 User Manual	SunnyBoy HF Series 2000, 2500, 3000 Manual
SunnyBoy 3000-6000TL Series Manual	SunnyBoy 1VL Series Manual v1.9	SunnyBoy 1AV Series Manual v1.8

Solar Inverter Recycling: - Recycling SMA SunnyBoy Solar Inverters

SMA SunnyBoy solar inverters contain valuable materials such as copper and aluminium, these materials are in high demand and recycling them is significantly less energy intensive than extracting them from ore.

If you find yourself with a damaged or faulty SMA SunnyBoy solar inverter, we will be pleased to help you recycle it.

There is no charge for this service but all costs involved with decommissioning and transportation are covered by you.
If you're delivering an inverter to us in person, although it's usually no trouble to arrange other days, the most convenient time for us is between 9am and 2pm on a Saturday, please let us know of your visit with an approximate time in advance.
We do not buy or sell used solar inverters or used solar inverter parts. For UK buyers and sellers, we've found ebay to be the best place for buying used solar inverters and inverter parts.
We can accept deliveries by courier at all times throughout the week but please contact us before you arrange this.
We can also help to recycle solar panels, solar batteries and solar mounting equipment.

Solar PV System Repairs

All services

Solar Power System Testing, Servicing & Maintenance

Regular solar PV system testing, servicing and maintenance will extend the life of a solar PV system and ensure that solar panels are always operating safely and at their best, whilst maximising yields.

We offer complete safety and performance testing for solar PV power systems of any size. Includes solar panels, cables, solar inverters, isolators and mains connections.

We provide solar power system testing and maintenance services for residential, commercial, industrial and agricultural clients across Southern, South West England and the West Midlands, with specialist experience working with farmers, developers and commercial and industrial buildings owners.

Solar Power System Testing, Servicing & Maintenance

Solar PV Inverter Replacement

If you have a faulty solar inverter, we offer an efficient, value for money, hassle free solar inverter replacement service. We offer good advice and install quality equipment with comprehensive warranty and support options. We will test the rest of the system as part of the service, take care of all hardware deliveries, record the new unit's serial number and confirm the warranty details with the manufacturer.

Our solar electricians work cleanly and will dispose of any unwanted boxes, faulty equipment and packaging.

Many modern solar inverters can now use wireless home networks to transmit solar generation data to PCs, tablets and smartphones, so if you would like something like this, let us know and we will be happy to set it up as part of the installation.

Solar PV Inverter Replacement

Solar PV Systems & Equipment, including Electrical & Roofing Systems

Grid-tie inverters, Hybrid Inverters, AC Coupled Inverters, Battery Storage Inverters, Off-Grid Inverters, Charge Controllers, Transfer Switches, Hot Water Controllers, Optimisers, Lithium Batteries, Lead Acid Batteries, Solar Panels, Mounting Systems, Test Equipment, Earthing Equipment, Electrical Distribution Equipment, Cable and Accessories

Deliveries to anywhere in the UK are quick, tracked and accurate, technical support (by phone and on site if needed) and design/product advice is available before, during and after installation. The recording and collating of serial numbers, factory and other test results, manuals any other information required for equipment warranties, add ons and extensions is included.

Trade, DIY and Retail Clients Welcome.

Bespoke system design, equipment testing and integration support as well as on-site technical support and job/equipment specific training is available for off-grid, hybrid, larger and or more complex systems.

All Systems

Mains/Grid Isolation and Surge Protection

Mains/AC Surge Protection Solar PV Systems

A whole house surge protector is installed to provide protection from transient overvoltages originating from the mains/grid. A whole house surge protector is installed directly inline and as close as possible to the incoming mains/grid supply meter, this allows for surge protection for all circuits and equipment including solar inverters, routers, stereos and other sensitive electrical equipment within the network. The addition of a 100Amp lockable isolator also allows for safe and convenient isolation of all electrical equipment within the network including consumer units, solar inverters, battery storage units and EV chargers from the mains/grid in one place.

Surge protectors are in compliance with the recently updated 18th edition amendment 2 of BS7671.

Mains/Grid Isolation and Surge Protection

All services

Articles: Further Information, Calculators & Solar Inverter Fault Codes

Lots of articles, calculators and technical information including links for further reading. Covering a range of topics related to the installation and maintenance of solar photovoltaic and electrical systems in the UK.

SMA Tripower Inverter Faults and Repairs

German solar inverter specialists SMA have been a leading manufacturer in renewable energy technologies for the last 35 years. SMA's three phase Tripower solar inverters come in a range of power ratings and have been widely installed in the UK for many years, some of the most popular being the transformerless STP-10000TL, STP-12000TL, STP-15000TL and the STP-17000TL.

BSI - PAS 63100:2024 - Protection Against Fire of Battery Energy Storage Systems for use in Dwellings

This Publically Available Specification (PAS) from the British Standards Institution (BSI) was sponsored by The Department for Energy Security and Net Zero. Although not yet a British Standard, this guidance was developed in response to an urgent demand for clarity as to good practice across the industry including product, service and process standards.

How to provide power to a house using a portable generator

We look at changeover switches, the importance of earthing, generator loadings, isolating non essential loads. Where to locate the generator and how best to safely isolate the grid/mains power supply and switch to a generator supply.

Ground Faults, Isolation (ISO) Faults, RISO Low Faults and Insulation Resistance Faults with Solar PV Systems

After a number of years exposed to wind, rain, snow, ice and sometimes animals; solar panel systems can start to develop faults. The most common faults we find related to exposure are ground faults, isolation (ISO) faults, RISO low faults and insulation resistance faults. In this article we take a look at what these faults are, the possible causes and what steps are taken to identify and resolve them.

All articles

What Our Customers Say:

"Glen was very helpful and very reasonably priced. I would recommend him, and use him again in future if I need any solar work." Venu Jega, Highworth

All testimonials

Case Studies

We've carried out Solar PV System design, installation, testing, repair and maintenance work on solar PV systems of all shapes and sizes all across the UK.

All case studies

Areas Served:

We are located in Wanborough, very close to Swindon in Wiltshire, Southern England, UK. From here we service clients within a 90 minute driving radius including the towns, cities and regions below:

Swindon: Abingdon, Aldbourne, Amesbury, Andover, Banbury, Basingstoke, Bath, Berkshire, Bicester, Blunsdon, Box, Bracknell, Bradford on Avon, Bridgwater, Bristol, Buckingham, Burford, Burnham on Sea, Calne, Camberley, Cardiff, Carterton, Cheltenham, Chippenham, Chipping Norton, Chipping Sodbury, Cirencester, Corsham, Cricklade, Devizes, Didcot, Evesham, Eynsham, Faringdon, Frome, Fleet, Glastonbury, Gloucester, Gloucestershire, Hampshire, Henley-on-Thames, Highclere, Highworth, Hook, Hungerford, Keynsham, Kingsclere, Lambourn, Lechlade, Ledbury, Ludgershall, Lyneham, Maidenhead, Malmesbury, Marlborough, Marshfield, Melksham, Minety, Newbury, Newport, Oxford, Oxfordshire, Pewsey, Purton, Ramsbury, Reading, Ross on Wye, Royal Wootton Bassett, Salisbury, Shaftesbury, Shalbourne, Slough, Southampton, Stow, Stratford upon Avon, Stroud, Swindon, Tewkesbury, Thatcham, Tidworth, Trowbridge, Wanborough, Wantage, Warminster, Weston Super Mare, Wiltshire, Winchester, Windsor, Witney, Wokingham, Worcester, Wroughton and Yate.

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Solar & Electrical | Services & Systems

SMA Sunnyboy Solar Inverter Faults and Repairs

SMA SunnyBoy Solar Inverter Faults and Warnings:

How to Restart a SMA SunnyBoy Solar Inverter:

SMA SunnyBoy Solar Inverter: No lights, No Display

SMA Sunnyboy Solar Inverter Fault Codes and Explanations:

SMA SunnyBoy TL Series Inverter Event Codes

SMA Sunnyboy Inverter Manuals:

Solar Inverter Recycling: - Recycling SMA SunnyBoy Solar Inverters

Areas Served: