JFY SunTwins Solar InverterJFY SunTwins Solar Inverter has a dual-string series of inverters which aims to provide a much better experience.

However there are several factors that may affect an inverter’s performance and cause failures, hence we have put together a list of fault displays and possible action from JFY Suntwins user manual for your convenience.

If any problems arise, the “Alarm” LED on the front panel will be red and the LCD displays the relevant information. Please note that safety measures should be observed to avoid any risk of injury or you may also seek assistance from a qualified electrician.

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No any display in LCD or LEDCheck PV-input connections
W01 No gridCheck grid connection cables.
W02 Vin overvoltageCheck the Voc of PV string, see if it is greater than or too close to max. input DC voltage of relative inverter type.
E01 Isolation errorCheck the impedance is between PV (+) & PV (-) and the PV-Inverter is earthed. The impedance must be greater than 2MΩ
E02 Leak errorThe leakage current is too high. Unplug the inputs from the PV string and check the peripheral AC system.
E03 Grid faultMake sure grid voltage and frequency meet the specifications.

Please note that during periods of little or no sunlight, the JFY JSI Solar Inverter may continuously start up and shut down. This is due to the insufficient power generated to operate the control circuits but this is not a trouble.

Here are some more fault messages that you may see on the JFY JSI front panel display.

System faultAuto Test FailedAuto Test does not pass
W01 No gridNo Utility, No Grid Connect
W02 Vin overvoltagePV panel Voltage is too high
E01 Isolation errorInsulation Problem of PV panel
E02 Ileak errorGFCI Fault, leakage current is too high
E03 Grid faultGrid voltage/frequency is out of range
Inverter faultE04 Coherence errorConsistent Fault
E05 Over temperatureInternal temperature abnormal
E06 Relay failureOutput relay Fault
E07 DCinj failureOutput Current DC Offset too high
E08 EEPROM failureEEPROM Fault
E09 Com. failureCommunication Fault
E10 DC bus OV.DC Bus over-voltage
E11 DC bus UV.DC Bus under-voltage
E12 Vref error2.5V Reference Voltage Fault
E13 DC sensor faultDC current sensor fault
E14 GFCI failureGFCI Device is damaged

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The full details are available in the JFY JSI solar inverter manual’s troubleshooting section.

If following the steps above does not fix the issue and your JFY JSI Solar Inverter is still within the warranty period you can contact the equipment installer or supplier. If your inverter is outside the warranty period we suggest that you contact a professional solar power expert. If you’re on the Gold Coast or Brisbane area contact Gold Coast Power Solutions here and we will be in touch to provide you with further assistance.

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