Understanding Fault Codes

One thing to remember the inverters go through very stringent tests at our factory they are tested for everything as well as long soak tests when the inverter leave the factory it is working perfectly any faults that appear I'll probably due to installation issues. The fault code table is really to help you identify issues or problems with other components within the installation


Default diagnostic is here to help you find problems with the system not cause problems, no very useful in localising an issue.


One thing to remember the inverters It is an Earth Fault on the solar panel This means one of the connections of the solar panel positive or negative is touching the ground. This. can be very dangerous this fault must be cleared you will need to check each solar panel/array to isolate the fault. ly to help you identify issues or problems with other components within the installation night again it is often caused by a heavy inrush current too many items switching on together. You need to separate y This is a very common fault when connecting inverters in parallel I can be quite infuriating what you're trying to commission a system basically means the communication cable is not working correctly, it can be caused by wrong type communication cable, wrong connection with the communication cable plugs, poor quality cable or a setting on one or moor inverters are incorrect. Another course can also be the in-line resistor is set incorrectly. If you experience this fault suggest to the following

F18 AC over current fault of hardware This is an overload on the “Load Terminal” Possibly caused by heavy surge current from air-conditioners. This is also quite a common fault can also because by a battery issue but generally it's caused by an rush current to the Load. Switch on at the same time. We have had experience where people have had F-18 faults during the night again it is often caused by an heavy in rush current too many items switching on together. You need to separate your essential and non-essential load only have essential on the load connection and none. Essential loads such. As AC on the. Grid side. Remember the inverter sends power from both the Grid connection and a the load connection F20 DC over current fault of the hardware This is normally caused by the battery not being able to deliver email to current inverting needs. Overcurrent on the battery. To clear this fault you must focus on the battery and battery discharge settings. You need to check the C rating of the battery, can the battery provide the current your system needs you may have an 8 kW inverter but unless the battery can supply 8 kW it will simply crash out.

  1. Check the battery C rating

  2. Check the maximum discharge the inverter is set to

  3. On the controller check the maximum power inverter can supply this is a global setting you can see this on the main controller

  4. Check the battery cables are heavy enough to meet the demands

  5. Hi current overload on start up may also cause this causes fault

F23 AC leakage current or transient over current This is a fault on the main side causing an earth leakage trip, double check all your mains cables coming in do a mega test or installation test on the cables to make sure there is no leakage. This leakage current is from the PV side, 1. Do a mega test or installaEon test on the cables to make sure there is no leakage. 2. Need check PV side ground connecEon. 3. Reset. The. System Page 40 of 43

F24 DC insulation impedance failure It is an Earth Fault on the solar panel This means one of the connections of the solar panel positive or negative is touching ground. This. can be very dangerous this fault must be cleared you will need to check each solar panel / array to isolate the fault. F26 The DC busbar is unbalanced When the hybrid in split phase mode, and the load of L1 and load of L2 is big different, it will report the F26. Mainly caused by the IGBT damaged F29 Parallel Coms cable fault This is a very common fault when connecting inverters in parallel I can be quite infuriating what you're trying to commission a system basically means the communication cable is not working correctly, it can be caused by wrong type communication cable, wrong connection with the communication cable plugs, poor quality cable or a setting on one or moor inverters are incorrect . Another course can also be the in-line resistor is set incorrectly. If you experience this fault suggest to the following

  1. Switch off all inverters and reset them

  2. Check each inverter has the correct and same operating system.

  3. Check the models are all the same.

  4. Replace the communication cable with shorter cables if possible ensure that the middle inverter is the master and slaves or other inverters radiate from the centre inverter, this keeps the communication cable as short as possible

  5. Check the port limiting resistors are set correctly.

  6. Check all your batteries are on the same bus bar

F35 No AC grid No AC grid is present This is a fairly simple one to find the problem with clearly have no power coming into the system so you need to fault find it on your AC supply F42 AC line low voltage AC upper and lower voltages are controlled by Grid set up page. If you are experiencing 42 faults then I would suggest that you adjust the great high and the grid low voltages from the great set up page If you are continually experiencing it then may be worthwhile fitting a data logger to see what is actually happening with the mains and contacting the power utility company because this is actually a problem with the supply coming into the property Page 41 of 43

F47 AC over frequency F48 AC lower frequency Check the frequency settings on the inverter system on the grid page, adjust the frequency slightly up all down to match with your grade. F56 DC busbar voltage is too low Generally cause with the battery problem possibly a damaged BMS. If you experience in M56 fault then you need to focus on the battery, the battery cables, the battery connections, battery discharging parameters and the the general condition of the battery.

  1. Check or battery cables are nice and tight good connections

  2. If using parallel checked all battery cables are the same length as the batteries are low voltage compare to the mains but very high current than the cable that is very important we should all be the same length

  3. Check the C rating of the battery

  4. Check the invert at maximum discharge setting

  5. Checked inverter maximum power setting ( Max sell Power )

F63 ARC fault Faulty connection on the solar panel causing noise Again this is a problem with the solar panel connections is actually a loose connection something is causing noise on the solar panel cable you can switch this off but it's better to try to locate the problem as this is a potential fire hazard. For this type of fault then you really need to go and check every single solar panel every single connection as sometimes his fault can appear from nowhere everything to be working and suddenly in the middle of the day this can happen. F64 sink high temperature failure Over temperature of the LGBT possibly caused by a blocked fan or blocked ventilation If this fault occurs if left too long can cause damage to the inverter.

  1. Switch off the inverter and allowed to cool down

  2. Clean all ventilation

  3. Ensure the fans are running correctly

  4. Check the environment is not too hot the inverter is in a very hot environment then you will need to reduce the power of the loading to the inverter as this would happen time and time again



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