ABB Aurora UNO 2.0/3.0/3.6/4.2 Inverter Status Error Codes

ABB Aurora UNO 2.0/3.0/3.6/4.2 Inverter State Error Codes

If your solar system uses an ABB Aurora UNO inverter and it develops a fault, contact AC Gold and we’ll get your solar PV system back up and generating electricity. If your Aurora inverter is still under warranty, the cost of repairing or replacing it will be covered by ABB.

Download ABB Aurora UNO 2.0/3.0/3.6/4.2 solar inverter manual.

When an ABB inverter develops a fault, it usually displays a error code to explain what is wrong. The following table lists the ABB Auroar UNO series inverter status codes so you can learn what your ABB Aurora PVI inverter is telling you and how to fix it. Looking for another Aurora Inverter Error Code?

Alarm Messages

The equipment is able to indicate errors/warnings on the display only if the input voltage is higher than the Vdcmin voltage (POWER LED flashing or on; see operation chapter).

The messages and their codes are indicated on the display


The following table shows all the possible activation combinations of LED’s on the LED panel according to the operating status of the inverter.

= LED On

= LED flashing

= LED Off

= Any one of the conditions described above

LED status Operating state
Green:
Yellow:
Red:
Firmware programming
The inverter firmware is being programmed
Green:
Yellow:
Red:
Night mode (inverter automatically switches off)
The inverter is in night time switch-off mode (input voltage less than 70% of the set start-up voltage).
Green:
Yellow:
Red:
Inverter initialisation
This is a transitional state due to the verification of the operating conditions. During this stage the inverter checks that the conditions for connecting to the grid are met.
Green:
Yellow:
Red:
The inverter is connected and is feeding power into the grid
Normal operation. During this stage, the inverter automatically tracks and analyses the
photovoltaic generator’s maximum power point (MPP).
Green:
Yellow:
Red:
Disconnection from the grid
Indicates no grid voltage. This condition does not allow the inverter to connect to the grid (the inverter display shows the message "Missing Grid").
Green:
Yellow:
Red:
Indication of Warning (W message codes) or Error (E message codes)
Indicates that the inverter control system has detected a warning (W) or error (E). The
display shows a message indicating the type of problem found (see Alarm messages).
Green:
Yellow:
Red:

Ventilation anomaly
Indicates an anomaly in the operation of the internal ventilation system that could limit output power at high ambient temperatures.

Failed association of internal inverter components (after replacement)
Indicates that the installed wiring box (only in the event of a replacement) was already
associated with another inverter and cannot be associated with the new inverter.
Overvoltage surge arresters triggered (where fitted)
Indicates that any class II overvoltage surge arresters installed on the AC or DC side have been triggered.
String protection fuses triggered (where fitted)
Indicates that one or more input string protection fuses that may be installed have been
triggered.
Autotest (for Italian grid standards only)
The inverter is performing an Autotest
Green:
Yellow:
Red:
Anomaly in the insulation system of the photovoltaic generator
Indicates that a leakage to ground from the PV generator has been detected, causing the
inverter to disconnect from the grid.

– Code on display
– Error message
– Signal
Name of alarm and cause Solution
– No code
– Ground F
Red LED
Ground fault of photovoltaic generator:
The alarm is generated when a leakage current to ground is detected in the DC section of the system.
  • Measure the insulation resistance using a megohmmeter positioned in the photovoltaic field (positive terminal short-circuited at the negative pole) compared to ground. The measurement is strongly influenced by the environmental conditions, so must be made under the same conditions in which the error occurred.
    – If the value measured is lower than 1 megaohm, a check must be carried out by a technician/installer on the photovoltaic generator to identify and eliminate the problem.
    – If the value measured is higher than 1 megaohm and the error signal persists, contact customer assistance
– No code
– NEW SYSTEM PART REFUSED!
Yellow LED lamp
Lack of linkage of the new system part:
The components inside the inverter (e.g. display, fuse board, communication and control board, etc.) are not inter-linked. This occurs following the replacement of one of the components inside the inverter.
  • Link the components inside the inverter by accessing the “Settings > Service > Accept boards” (refer to the procedure given in this manual).
    – If the signal persists also following the linking of the components, contact customer assistance.
– No code
– SET COUNTRY or NO NATION
No LED
SET COUNTRY or NO NATION:
Indicates that in the installation phase the grid standard was not set on the inverter.
  • Set the grid standard of the country of installation following the instructions given in this manual for the inverter.
    – If the signal persists also after the grid standard has been set, contact customer assistance.
– No code
– Missing Grid
Yellow LED
Missing Grid:
The inverter displays the “Missing Grid” message when it does not record output voltage (AC side).
  • Check the grid voltage on the inverter’s AC terminal block.
    – Should it be absent, check any protection work on the line and the presence of grid voltage on the supply point.
– No code
– Memory Fail
Yellow LED lamp
Memory fail:
The inverter displays the “Memory Fail” message when it records a communication problem with the memory board on which the inverter saves the daily value of energy produced.
  • Remove the memory board and check the welding of all the connector’s terminals. Subsequently reinsert the memory board and check that it is correctly inserted into the dedicated slot
    – If the signal persists also following the above checks, contact customer assistance.
– No code
– Waiting Sun
Green LED lamp
Waiting Sun:
The inverter displays the “Waiting Sun” message when, following a W001 and/or W002 notice, the voltage from the photovoltaic generator is less than the activation voltage (Vstart).
  • Check the input voltage on the inverter.
    – If it does not exceed Vstart, check for the presence of sufficient irradiation and the correct composition of the system.
    – If it exceeds Vstart, contact customer assistance
– W001
– Sun Low
Yellow LED
Insufficient irradiation (Low input voltage on switching on the inverter):
Incorrect configuration of the PV generator or an “on the limit” configuration for the inverter’s minimum input voltage.
  • Check the input voltage on the inverter.
    – If it does not exceed Vstart, check for the presence of sufficient irradiation and the correct composition of the system.
    – If it exceeds Vstart, contact customer assistance
– W002
– Input UV
Yellow LED
Insufficient irradiation (Low input voltage on switching off):
Incorrect configuration of the photovoltaic generator or an “on the limit” configuration for the inverter’s minimum input voltage
  • Check the input voltage on the inverter.
    – If it does not exceed Vstart, check for the presence of sufficient irradiation and the correct composition of the system.
    – If it exceeds Vstart, contact customer assistance
– W003
– Grid Fail
Yellow LED
Parameters of grid voltage outside range:
This error signal occurs when during the inverter’s normal operation the grid parameters exceed the limits set by the operator:
– Grid voltage absent (after the signal the inverter goes to "Missing Grid")
– Unstable grid voltage (down or up)
– Unstable grid frequency
  • Check the grid voltage on the inverter.
    – Should it be absent, check for absence of grid voltage on the supply point.
    – If, on the other hand, the voltage tends to rise (when the inverter is connected) there is high line or grid impedance.
    • Check the grid voltage also on the supply.
    – If it is high, it means that there is high grid impedance. In this case, ask the operator to adjust the grid voltage. If the operator authorises a change to the inverter’s parameters, agree the new limits with customer assistance
    – If the voltage at the point of supply is much lower than that measured on the inverter, it is necessary to adjust the line (inverter-contactor).
    – If the voltage and the grid frequency come back within the limits (also when the inverter is connected to the grid) contact customer assistance
– W004
– Grid OV
Yellow LED
Grid overvoltage:
This error signal occurs when during the inverter’s normal operation the grid voltage exceeds the maximum limit set by the operator.
  • Check the grid voltage on the inverter.
    If the voltage tends to rise (when the inverter is connected), there is a problem of high line or grid impedance.
  • Check the grid voltage also on the supply.
    – If it is high, it means that there is high grid impedance. In this case, ask the operator to adjust the grid voltage. If the operator authorises a change to the inverter’s parameters, agree the new limits with customer assistance
    – If the voltage at the point of supply is much lower than that measured on the inverter, it is necessary to adjust the line (inverter-contactor).
    – If the voltage and the grid frequency come back within the limits (also when the inverter is connected to the grid), contact customer assistance
– W005
– Grid UV
Yellow LED
Grid undervoltage:
This error signal occurs when during the inverter’s normal operation the grid voltage exceeds the minimum limit set by the operator.
  • Check the grid voltage on the inverter.
  • Check the grid voltage also on the supply:
    – If it is high, it means that there is high grid impedance. In this case, ask the operator to adjust the grid voltage. If the operator authorises a change to the inverter’s parameters, agree the new limits with customer assistance
    – If the voltage at the point of supply is much lower than that measured on the inverter, it is necessary to adjust the line (inverter-contactor).
    – If the voltage and the grid frequency come back within the limits(also when the inverter is connected to the grid), contact customer assistance
– W006
– Grid OF
Yellow LED
Grid over-frequency:
This error signal occurs when during the inverter’s normal operation the grid frequency exceeds the maximum limit set by the operator.
  • Check the grid frequency in the inverter.
  • Check the grid frequency also on the supply:
    – If the voltage and the grid frequency come back within the limits (also when the inverter is connected to the grid), contact customer assistance
– W007
– Grid UF
Yellow LED
Grid under-frequency:
This error signal occurs when during the inverter’s normal operation the grid frequency exceeds the minimum limit set by the operator
  • Check the grid frequency in the inverter.
  • Check the grid frequency also on the supply:
    – If the voltage and the grid frequency come back within the limits (also when the inverter is connected to the grid), contact customer assistance
– W009
– Empty Table
Yellow LED
Characterisation board for the wind generator not compiled (only WIND models) (only WIND models)
– W010*
– Fan Fail
Yellow LED
Fan Fail:
This error occurs when there is a malfunction in the fan/fans inside the inverter.
  • Error inside the inverter and cannot be checked externally.
    – If the alarm repeats persistently, contact customer assistance
– W011
– Bulk UV
Yellow LED
Low “Bulk” voltage (DC-DC circuit):
The alarm (which is a warning and not an error) is generated when the voltage at the heads of the bulk capacitors does not reach the threshold for the operation of the inverter (internal unchangeable threshold).
  • Raise the value of the activation voltage (Vstart) so as to have sufficient power from the PV generator at the time of the inverter’s grid connection.
    • Check the input voltage on the inverter.
    – If it does not exceed Vstart, check for the presence of sufficient irradiation and the correct composition of the system.
    – If it exceeds Vstart, contact customer assistance
– W012*
– Batt. Low
Yellow LED
*not visualised on display
Battery Low:
The inverter displays the “Battery Low” message when it records a voltage for the buffer battery which is too low.
  • Check that the date/time are set correctly and, if they are not, set them.
    Subsequently arrange to completely switch off the inverter (on both AC and DC) and wait a few minutes.
    Finally, restart the inverter and check whether the date/time are now correctly set or whether they have reset to 01/01/2000.
    In this case replace the battery with the inverter completely switched off (section AC and DC side) being careful to maintain the polarity
– W013*
– Clock Fail
Yellow LED lamp.
*not visualised on display
Clock Fail:
The alarm occurs when there is a difference of over 1 minute in the time displayed compared to the internal time of the microprocessors and indicates a malfunction of the clock circuit.
Error inside the inverter and cannot be checked externally.
– If the alarm repeats persistently, contact customer assistance.
– W015
– Island Detect
Yellow LED
Disconnection due to Anti-Islanding:
The inverter has been improperly connected to an island grid.
  • Check that the grid to which the inverter is connected is not an island grid.
    – If the grid to which the inverter is connected is an island grid, switch the inverter off and then on again: if the problem persists, contact customer assistance.
– W017*
– String Err.
Yellow LED
* (only for models with monitored string fuses)
Error recorded in measuring string currents:
Damaged string protection fuse(s)
  • Check with a multimeter the state of the fuses (positioned on the fuse boards).
    – If one or more fuses is open, arrange to replace them and check that the input current on the string(s) does not exceed the rating of the fuses (should parallel strings have been made
    outside the inverter).
    – If there are no damaged string fuses and the inverter continues to show the alarm message check whether the settings to be made through the Aurora Manager software are correct (presence or absence of one or more input strings).
– W018*
– SPD DC Err.
Yellow LED lamp
* (only for models with monitored string fuses)
Intervention of overvltage surge arresters on DC side:
Damaged overvoltage surge arresters positioned on DC side
  • Observe the inspection window on each surge arrester (DC side). If it is red, the surge arrester is damaged and the cartridge must be replaced.
    – If the alarm status persists, even if all the surge arresters have a green inspection window, contact customer assistance.
– W019*
– SPD AC Err.
Yellow LED lamp
* (only for models with monitored string fuses)
Intervention of overvoltage surge arresters on AC side:
Damaged overvoltage surge arresters positioned on AC side
  • Observe the inspection window on each surge arrester (AC side). If it is red, the surge arrester is damaged and the cartridge must be replaced.
    – If the alarm status persists, even if all the surge arresters have a green inspection window, contact customer assistance.
– W022*
– Reactive power mode changed
Yellow LED lamp
* (not visualised on display)
Variation in means of managing reactive power:
Variation in the means of managing reactive power; this change can be made through the display or advanced configuration software.
The variation in the means of managing reactive power is done directly by the customer/installer and is not an error. The information is only saved on the historic record of the events memorised by the inverter
– W023*
– date/time changed
No LED
* not visualised on display
Variation in the inverter’s date and time:
Variation of the inverter’s date and time; this change can be made through the display or advanced configuration software.
  • The variation in the inverter’s date and time is done directly by the customer/installer and is not an error. The information is only saved on the historic record of the events memorised
    by the inverter
– W024*
– Energy data reset
No LED
* not visualised on display
Zeroing of the statistical energy data memorised in the EEPROM:
Reset of the energy data saved in the inverter; this operation can be handled through the display or advanced configuration software.

The zeroing of the partial energy values memorised by the inverter is done directly by the customer/installer and is not an error. The information is only saved on the historic record of the events memorised by the inverter

  • The notice may also occur on substitution of the Memory Card where the statistical production data is saved
– W026*
– AFDD user reset
No LED
* not visualised on display
Reset of the Arc Fault error:
Manual reset of the Arc Fault error; this operation can be made through the display or advanced configuration software.
The reset of the Arc Fault error is done directly by the customer/installer and is not an error. The information is only saved on the historic record of the events memorised by the inverter
– W027*
– Latch-Manual reset
No LED
* not visualised on display
Resetting of the Latch alarm conditions:
Manual reset of the Latch alarm conditions; this operation can be made through the display or advanced configuration software.
The reset of the Latch alarm conditions is done directly by the customer/installer and is not an error. The information is only saved on the historic record of the events memorised by the inverter
– W046
– Grid conn. fault
Yellow LED
Connection to the grid unsuccessful
The alarm is logged when a Missing grid or Input UV error occurs or due to the manual disconnection of the inverter during the grid connection sequence
  • Once the error occurs, the inverter tries to return to normal operation.
    If the problem persists after a number of attempts to connect the inverter, switch the inverter off and then on again.
    – If the problem persists (once the inverter has been switched off and back on again), contact customer assistance.
– W047
– Update Incomplete
Yellow LED
FW update method unsuccessful
The alarm occurs when a firmware update has not been completed.
  • Complete any pending firmware updates.
    – If the problem persists once the firmware updates have been completed, switch the inverter off and on again.
    – If the problem persists (once the inverter has been switched off and back on again), contact customer assistance.
– W048
– Update Incomplete
Yellow LED
Automatic disconnection from the grid due to time limit:
If the inverter exceeds the set grid connection time limit set by the grid standard, it will automatically have to carry out a disconnection and reconnection to the grid to carry out the Riso test.
  • The presence of this alarm is not an error as the automatic disconnection is prescribed by safety regulations.
    – If the inverter disconnects in a shorter time than expected, contact customer assistance.
– W049*
– Global-Setting Event
No LED
*not visualised on display
Variation of the grid standard
Variation of the inverter’s grid standard; this change can be made through the display or advanced configuration software.
  • The variation in the inverter’s grid standard is done directly by the customer/installer and is not an error. The information is only saved on the historic record of the events memorised
    by the inverter
– W051
– Exit from Stand Alone connection
Yellow LED
Exit from Stand-alone mode:
The alarm is logged when the "Stand Alone" mode is deactivated or the inverter reconnects to the grid (this can only be seen if the Stand Alone accessory board has been installed).
  • Deactivation of the Stand Alone mode is done directly by the customer/installer or automatically by the inverter and is not an error.
– W058
– System Frozen
Yellow LED
Converter in locked state:
The converter lock state is connected to an installation phase in which the starts-up and grid connection conditions are not yet present.
  • Complete the commissioning phase of the inverter.
    – If the problem persists (once the commissioning phase has been completed and the inverter has been switched off and back on again), contact customer assistance.
– W059
– Output power Overload
Yellow LED
Overload on Stand-alone output:
The alarm occurs when there is an excessive request for power by the grid with the inverter in "Stand Alone" mode (this can only be seen if the Stand Alone accessory board has been installed).
  • Disconnect one or more loads from the Stand Alone output.
    – If the problem persists (once all loads have been disconnected and the inverter has been switched off and back on again), contact customer assistance.
– E001
– Input OC
Yellow LED
Input over-current (photovoltaic generator):
The alarm occurs when the inverter’s input current exceeds the inverter’s threshold for maximum input current
  • Check whether the composition of the PV generator enables input current which exceeds the maximum threshold allowed by the inverter and that the configuration of the inputs (independent or in parallel) is carried out correctly.
    – If both checks are positive, contact customer assistance.
– E002
– Input OV
Yellow LED

Input overvoltage (photovoltaic generator):
The alarm is generated when the input voltage (from the PV generator) exceeds the inverter’s threshold of maximum input voltage.
The alarm occurs before reaching the absolute threshold over which the inverter is damaged.

When the inverter’s input voltage exceeds the overvoltage threshold, the inverter will not start up due to the generation of the alarm.

  • It is necessary to measure the input voltage inside the inverter with a voltmeter.
    – If it is higher than the maximum voltage of the operating range, the alarm is genuine and it is necessary to check the configuration of the PV generator. If the voltage has also exceeded the
    maximum input threshold the inverter could be damaged.
    – If it is lower than the maximum voltage of the operating range, the alarm is caused by an internal malfunction and it is necessary to contact customer assistance.
– E003
– Input OC
Yellow LED
DSP initialisation error:
The main microcontroller cannot initialise correctly the two DSPs (booster stage and inverter stage). The error is caused by communication problems on the inverter’s internal bus.
  • Error inside the inverter and cannot be checked externally.
    – If the problem persists (once the inverter has been switched off and back on again), contact customer assistance.
– E004
– Bulk OV
Yellow LED
“Bulk” over-voltage (DC-DC circuit):
Error inside the inverter. The alarm is raised when the voltage at the heads of the bulk capacitors exceeds the overvoltage threshold (internal unchangeable threshold).
  • The alarm may be triggered by causes external to the inverter:
    – An excessive input voltage can be recorded as a condition for bulk overvoltage. In this case it is advisable to check the inverter’s input voltage and should this value be close to the input OV
    threshold, review the configuration of the photovoltaic generator.
    – Excessive grid voltage could cause the bulk voltage to rise in uncontrolled fashion with a consequent protection intervention and hence generation of the alarm. In these cases the alarm is
    transitory and the inverter automatically restarts
    – The alarm may be triggered by causes inside the inverter and in this case it is necessary to contact customer assistance.
– E005
– Comm. Error
Yellow LED
Communication error inside the inverter:
The alarm occurs when there are communication problems between the control devices inside the inverter.
  • Error inside the inverter and cannot be checked externally.
    – If the problem (once the inverter has been switched off and back on) persists, contact customer assistance.
– E006
– Output OC
Yellow LED
Output overcurrent:
The alarm occurs when the inverter’s output current exceeds the inverter’s threshold for maximum output current.
  • Error inside the inverter and cannot be checked externally.
    – If the problem (once the inverter has been switched off and back on) persists, contact customer assistance.
– E007
– IGBT Sat
Yellow LED
Saturation recorded on the IGBT components:
The alarm occurs when one of the inverter’s active devices is in a saturated state.
Once the error occurs, the inverter tries to return to normal operation.
– Should the error occur sporadically, it may be caused by a brusque transition of the
grid voltage or of the input voltage, but is not due to a malfunction by the inverter.
– If the error is connected to an internal breakdown, it will continue to appear and so it is necessary to contact customer assistance.
– E009
– Internal error
Yellow LED
Error inside the inverter:
Error inside the inverter
  • Error inside the inverter and cannot be checked externally.
    – If the problem (once the inverter has been switched off and back on) persists, contact customer assistance.
– E010
– Bulk Low
Yellow LED
Low “Bulk” voltage (DC-DC circuit):
The alarm may be triggered by causes external to the inverter: a reduced input voltage on the inverter (just above the activation voltage) but which is not accompanied by a sufficient availability of power from the photovoltaic generator (typical condition of the stages with limited irradiation)
– If the error signal occurs sporadically, it may be due to causes external to the inverter (limited irradiation and so limited power availability from the PV generator).
– If the problem occurs systematically also in conditions of high irradiation and with input voltage which is significantly higher than the activation voltage, contact customer assistance.
– E011
– Ramp Fail
Yellow LED
Long wait for “Booster” regime to start:
Error internal to inverter relating to start up time for DC-DC circuit regime (Booster)
  • Error inside the inverter and cannot be checked externally.
    – If the problem (once the inverter has been switched off and back on) persists, contact customer assistance.
– E012
– DcDc Fail
Yellow LED
Error in the “Booster” circuit (DC-DC side) recorded by the “Inverter” circuit (DC-AC side):
Error internal to inverter relating to operation of the DC-DC circuit regime (Booster)
  • Error inside the inverter and cannot be checked externally.
    – If the problem persists (once the inverter has been switched off and back on again), contact customer assistance.
– E013
– Wrong Mode
Yellow LED
Incorrect configuration of inputs (set in parallel rather than independent):
The alarm is generated solely when the inverter is configured with parallel inputs. In this particular configuration the inverter checks the input voltage of each of the two channels and if the two voltages differ by more than 20Vdc, the alarm is raised.
  • Check that the setting of the "IN MODE" switch is specifically set to "PAR" and that the bridges between the two input channels have been included.
    – If the configuration of the inverter is correct, check that the input strings have the usual number of standard panels of the usual brand and with the same inclination/orientation.
    – If both the configuration of the inverter and the characteristics of the PV generator conform with the specifications, contact customer assistance.
– E014
– Over Temp.
Yellow LED
Excessive temperature inside the inverter:
External temperature over 60°C. This parameter also depends on the power which the inverter must supply since the measurement of temperatures is done internally and is influenced by the heat dissipated by the components of the inverter itself
Check that the inverter is not exposed to direct sunlight. Wait for the temperatures to which the inverter is exposed to return to the operating range and for the inverter to cool down.
– If the problem (once the ambient temperature has returned to the range) persists, contact customer assistance. Remember to wait the time needed to allow the inverter to cool down
– E015
– Bulk Cap Fail
Yellow LED
Fault recorded on the “Bulk” capacitor:
Error inside the inverter relating to a problem in the bulk capacitors.
  • Error inside the inverter and cannot be checked externally.
    – If the problem persists (once the inverter has been switched off and back on again), contact customer assistance.
– E016
– Inverter Fail
Yellow LED
Error in the “Inverter” circuit (DC-AC side) recorded by the “Booster” circuit (DC-DC side):
The alarm is generated when a problem is recorded in the inverter circuit (DC/AC)
  • Error inside the inverter and cannot be checked externally.
    – If the problem persists (once the inverter has been switched off and back on again), contact customer assistance.
– E017
– Start Timeout
Yellow LED

Long wait for “Inverter” regime to start up:
Error internal to inverter relating to start-up time for the DC-AC circuit regime (Inverter)

  • The alarm may be triggered by causes external to the inverter: a reduced input voltage on the inverter (just above the activation voltage) but which is not accompanied by a sufficient availability of power from the photovoltaic generator (typical condition of the stages with limited irradiation)
– If the error signal occurs sporadically, it may be due to causes external to the inverter (limited irradiation and so limited power availability from the PV generator).

– If the problem occurs systematically also in conditions of high irradiation and with input voltage which is significantly higher than the activation voltage, contact customer assistance.

– E018
– Ground Fault
Red LED
High leakage current measured on the DC side (photovoltaic generator):
The alarm is generated when, during normal operation of the inverter, a leakage current to ground is detected in the DC section of the system. It is also possible that the inverter generates the alarm E018 message also due to AC leakage currents connected to the capacitive nature of the photovoltaic generator compared to ground.
  • Measure the insulation resistance using a megohmmeter positioned in the photovoltaic field (positive terminal short-circuited at the negative pole) compared to ground. The measurement is
    strongly influenced by the environmental conditions, so must be made under the same conditions in which the error occurred.
    – If the value measured is lower than 1 megaohm, a check must be carried out by a technician/installer on the photovoltaic generator to identify and eliminate the problem.
    – If the value measured is higher than 1 megaohm and the error signal persists, contact customer assistance.
– E019
– Ileak sense. fail
Yellow LED
Failure of test on sensor to measure the leakage current (DC side):
Before connecting to the grid the inverter runs a autotest regarding the sensor for the leakage current. The test is carried out by “forcing", in the sensor of the leakage current, a current with a known value: the microprocessor compares the value read with the known value. The error is generated if the comparison between the read value and the known value during the test does not fall within the allowed tolerance.
  • Error inside the inverter and cannot be checked externally.
    By its nature, the alarm only occurs prior to connection to the grid
    – If the problem (once the inverter has been switched off and back on) persists, contact customer assistance.
– E020
– Self Test Error 1
Yellow LED
Failure of the test on the relay of the “Booster” (DC-DC circuit):
Before connecting to the grid the inverter carries out internal tests. One of these tests concerns the correct operation of the booster relay. The test is carried out by “forcing” the switching of the relay and checking its operation.
The error is generated if a problem is found in actioning the relay.
  • Error inside the inverter and cannot be checked externally.
    By its nature, the alarm only occurs prior to connection to the grid
    – If the problem persists (once the inverter has been switched off and back on again), contact customer assistance.
– E021
– Self Test Error 2
Yellow LED
Failure of the test on the inverter’s relay (DC-AC circuit):
Before connecting to the grid the inverter carries out internal tests. One of these tests concerns the correct operation of the inverter relay. The test is carried out by “forcing” the switching of the relay and checking its operation. The error is generated if a problem is found in actioning the relay.
  • Error inside the inverter and cannot be checked externally.
    By its nature, the alarm only occurs prior to connection to the grid
    – If the problem persists (once the inverter has been switched off and back on again), contact customer assistance.
– E022
– Self Test Error 4
Yellow LED
Timeout of the tests undertaken on the relays inside the inverter:
Execution time for the autotest carried out on the relay of the DC-AC (inverter) circuit too high. It may indicate a problem connected to the aforementioned relays
  • Error inside the inverter and cannot be checked externally.
    – If the problem persists (once the inverter has been switched off and back on again), contact customer assistance.
– E023
– DC in error
Yellow LED
Feeding of direct current to grid outside of range:
The error is generated if the continuous component of the current supplied to the grid exceeds the threshold of 0.5% of the normal operating current.
In any case the inverter is not blocked due to the E023 error, but tries to reconnect to the grid.
The sporadic repetition of the error is a sign of serious grid distortions or sharp irradiation changes, while systematic repetition of the error signal will indicate a breakdown on the inverter
Once the error occurs, the inverter tries to return to normal operation.
– Should the error occur sporadically, it may be caused by a brusque transition of the
grid voltage or of the input voltage, but is not due to a malfunction by the inverter.
– If the error is connected to an internal breakdown, it will continue to appear and so it is necessary to contact customer assistance.
– E024
– Internal error
Yellow LED
Error inside the inverter:
Error inside the inverter
  • Error inside the inverter and cannot be checked externally.
    – If the problem persists (once the inverter has been switched off and back on again), contact customer assistance.
– E025*
– Riso Low
Yellow LED
*not visualised on display
Low value of insulation resistance:
Before connecting to the grid the inverter measures the insulation resistance of the PV generator compared to ground. Should the measurement of the insulation resistance be below 1Mohm, the inverter does not connect to the grid and shows the “Riso Low” error. The causes may be:
– PV panel(s) damaged;
– Junction box(es) of the panels not correctly sealed, so as to permit infiltration by water and/or
humidity;
– Problem in connections between panels (not perfectly fit);
– Poor quality of cable joints;
– Presence in the DC section of unsuitable or damaged overvoltage surge arresters outside the inverter (reduced ignition voltage compared to the characteristics of the strings of the PV generator);
– Presence of humidity inside any junction box
  • Measure the insulation resistance using a megohmmeter positioned in the photovoltaic field (positive terminal short-circuited at the negative pole) compared to ground. The measurement is strongly influenced by the environmental conditions, so must be made under the same conditions in which the error occurred.
    – If the value measured is lower than 1 megaohm, a check must be carried out by a technician/installer on the photovoltaic generator to identify and eliminate the problem.
    – If the value measured is higher than 1 megaohm and the error signal persists, contact customer assistance.
– E026
– Vref Error
Yellow LED
Internal reference voltage outside of range:
Wrong measurement of reference voltage inside inverter
  • Error inside the inverter and cannot be checked externally.
    – If the problem persists (once the inverter has been switched off and back on again), contact customer assistance.
– E027
– Error Meas V
Yellow LED
Grid voltage outside of range:
Error in the internal measurement of grid voltage (set by law) in order to have a redundant measurement (2 measurements on the same parameter made by two different circuits)
  • Error inside the inverter and cannot be checked externally.
    – If the problem persists (once the inverter has been switched off and back on again), contact customer assistance.
– E028
– Error Meas F
Yellow LED
Grid frequency outside of range:
Error in the internal measurement of grid frequency (set by law) in order to have a redundant measurement (2 measurements on the same parameter made by two different circuits)
  • Error inside the inverter and cannot be checked externally.
    – If the problem persists (once the inverter has been switched
    off and back on again), contact customer assistance.
– E029
– Error Meas F
Yellow LED
Internal overvoltage on the measurement of the “Mid bulk”:
Error inside the inverter (only triphase models)
  • Error inside the inverter and cannot be checked externally.
    – If the problem persists (once the inverter has been switched off and back on again), contact customer assistance.
– E030
– Error Meas Ileak
Yellow LED
High leakage current (DC side):
Error in the internal measurement (made when the inverter is grid connected) of the leakage current of the DC side (PV generator) compared to ground (set by law) in order to have a redundant measurement (2 measurements on the same parameter made by two different circuits)
  • Error inside the inverter and cannot be checked externally.
    – If the problem persists (once the inverter has been switched off and back on again), contact customer assistance.
– E031
– Error Read V
Yellow LED
Output relay damaged:
Measurement of internal voltage on heads of the output relay outside of range. There is too great a difference in voltage between the input and output of the grid connection relay.
  • Error inside the inverter and cannot be checked externally.
    – If the problem persists (once the inverter has been switched off and back on again), contact customer assistance.
– E032
– Error Read I
Yellow LED
Imbalanced output currents:
Measurement of the imbalance in the output voltage (carried out across the three phases) outside of range (only in triphase models)
  • Error inside the inverter and cannot be checked externally.
    – If the problem persists (once the inverter has been switched off and back on again), contact customer assistance.
– E033
– UTH
Yellow LED
Low ambient temperature:
Temperature outside the inverter below -25°C
  • Wait for the temperatures to which the inverter is exposed to return to the operating range.
    – If the problem persists, contact customer assistance. Remember to wait the time needed to allow the inverter to warm up
– E034
– Interlock fail
Yellow LED
“IGBT” circuitry not ready:
Error inside the inverter
  • Error inside the inverter and cannot be checked externally.
    – If the problem persists (once the inverter has been switched off and back on again), contact customer assistance.
– E035*
– Remote Off
Yellow LED
*not visualised on display
Inverter awaiting “remote ON” command:
The inverter has been switched off remotely (remote OFF) and remains awaiting the signal which will switch it back on (Remote ON)
  • Switch the inverter back on remotely. If the unit does not switch back on, disable the remote off/on function and switch the equipment off completely and subsequently switch it back on.
    – If the problem persists (once the Remote ON/OFF function from the display has been reactivated), contact customer assistance.
– E036
– Vout Avg error
Yellow LED
Average of the measurements of grid voltage outside of range:
The average value of the grid voltage (sampled every 10 minutes) does not fall within the permitted ranges. The grid voltage in the point connected to the inverter is too high. This may be caused by too high a grid impedance. In the final stage of the timeout, the inverter limits the
power to check whether the grid voltage has stabilised into regular parameters. If this does not happen, the inverter disconnects from the grid
  • Check the grid voltage in the connection point to the inverter.

    – If the grid voltage differs from the range due to the conditions of the distribution grid, ask the operator to adjust the grid voltage. If the operator authorises a change to the inverter’s parameters, agree the new limits with customer assistance

– E037
– Riso Low
Red LED
Low value of the insulation resistance (only with the “Amorphous” mode activated):
This error can occur only should the “Amorphous” mode be on. This function is on only in inverters
equipped with a grounding kit and serves to monitor the voltage at the heads of the grounding resistance. The error occurs when the voltage at the heads of the resistance connected between ground and the pole of the photovoltaic generator exceeds 30V for more than 30 minutes or 120V for more than one second.
  • Check for the presence and correct contact between the two terminals of the grounding resistance installed inside the inverter
    • Measure the insulation resistance using a megohmmeter positioned in the photovoltaic field (positive terminal short-circuited at the negative pole) compared to ground. The measurement is
    strongly influenced by the environmental conditions, so must be made under the same conditions in which the error occurred.
    – If the value measured is lower than 1 megaohm, a check must be carried out by a technician/installer on the photovoltaic generator to identify and eliminate the problem.
    – If the value measured is higher than 1 megaohm and the error signal persists, contact customer assistance.
– E046
– String self test fail
No LED
Error during the automatic check of the string voltages (only in models with the “fuse-control”
board):

In some inverter models it is possible to carry out the check test of the polarity of the strings connected to the input (e.g.:TRIO-20.0/27.6kW).
This error signal occurs when, during the test stage, an inverted string is recorded
  • Section the inverter and check the polarity of the string(s) which the inverter has recorded as inverted.
    – Once all the strings have been correctly connected, activate the system once again; the inverter will once again check the correct polarity of the string inputs at the end of which it will carry out the checks for the grid connection.
    – If the problem persists (once the inverter has been switched off and back on again), contact customer assistance.
– E049
– AC FF Error
Yellow LED
Error in the “AC feed-forward” circuit:
Error inside the inverter
  • Error inside the inverter and cannot be checked externally.
    – If the problem persists (once the inverter has been switched off and back on again), contact customer assistance.
– E050
– AFDD Fault
Red LED
Arc Fault protection activated:
Possible photovoltaic arc detected on the DC side.
  • If it is the first time this problem has occurred, press the ESC button for 5 seconds and wait for the unit to restart.
    – If the problem persists (once the inverter has been switched off and back on again), contact customer assistance.
– E053
– AFDD comm. Fault
Yellow LED
Arc Fault board autotest failed:
Problem detected during the AFDD board autotest phase.
  • Error inside the inverter and cannot be checked externally.
    – If the problem persists (once the inverter has been switched off and back on again), contact customer assistance.
– E054
– AFDD comm. Fault
Yellow LED
Arc Fault board communication error:
Error on the RS485 serial communication detected between the inverter and the AFDD board.
Error inside the inverter and cannot be checked externally.
– If the problem persists (once the inverter has been switched off and back on again), contact customer assistance
– E055
– AFDD wrong conf.
Yellow LED
Arc Fault board parameter reading error:
Error in the parameter reading by the system.
  • Error inside the inverter and cannot be checked externally.
    – If the problem persists (once the inverter has been switched off and back on again), contact customer assistance.
– E056
– Over Temp. (from external box)
Yellow LED
Excessive temperature measured inside the inverter’s wiring box:
High internal temperature.
This error relates to the temperature measured on external boxes (e.g.:TRIO-20.0/27.6kW).
  • Check that the inverter is not exposed to direct sunlight. Wait for the temperatures to which the inverter is exposed to return to the operating range and for the inverter to cool down.
    – If the problem (once the ambient temperature has returned to the range) persists, contact customer assistance. Remember to wait the time needed to allow the inverter to cool down
– E057
– Vbulk reading error
Yellow LED
Input voltage (Vin) higher than booster voltage (Vbulk):
The error occurs if the input voltage exceeds the Bulk voltage (voltage on the DC-DC circuit inside the inverter)
  • It is necessary to measure the input voltage inside the inverter with a voltmeter.
    – If it is higher than the maximum voltage of the operating range, the alarm is genuine and it is necessary to check the configuration of the PV generator. If the voltage has also exceeded the
    maximum input threshold the inverter could be damaged.
    – If it is lower than the maximum voltage of the operating range, the alarm is caused by an internal malfunction and it is necessary to contact customer assistance.
– E058
– Pin vs Pout check error
Yellow LED
Error in the check of Pin vs Pout:
The error occurs if the difference between the measured value of input power and that of output power is greater than the limit imposed internally to the inverter.
  • Error inside the inverter and cannot be checked externally.
    – If the problem persists (once the inverter has been switched off and back on again), contact customer assistance
– E077
– Internal Error
Yellow LED
Error in the system configuration:
Error inside the inverter
  • Error inside the inverter and cannot be checked externally.
    – If the problem persists (once the inverter has been switched off and back on again), contact customer assistance.
– E078
– Riso Test fail
Yellow LED
Riso test error:
Problem detected during the Riso test phase.
  • Error inside the inverter and cannot be checked externally.
    – If the problem persists (once the inverter has been switched off and back on again), contact customer assistance.
– E079
– Wrong Sequence
Yellow LED
Incorrect Phases connection
(Only triphase models) The phases have not been connected correctly to the AC output
  • Invert two of the phases of the network wiring to the AC terminal block of the inverter.
– E081
– Internal Error
Red LED
Inverter fault / Incomplete inverter closing:
Fault inside the inverter or incomplete inverter closing (front cover missing or not tightened, cable glands missing or incorrectly tightened, environmental protection IP65 not guaranteed)
  • If the problem has occurred during the installation phase or during the inverter maintenance phase (therefore the cover has been removed or the cable glands have been acted upon), carry out the following operations:
    – Disconnec the AC grid and DC input from the inverter and check for the front cover and all the cable glands, also checking their correct tightening to ensure environmental protection IP65; reconnect the AC grid and the DC input and attempt to switch the inverter on; if the problem persists, contact customer assistance:
    – If the front cover and all cable glands are present, disconnect the AC grid and DC input from the inverter and wait 15 minutes at a safe distance, then open the inverter cover and if no smoke/smell of burning is present, check the integrity of the components or the presence of moisture or other abnormal conditions; reconnect the AC grid and DC input and attempt to switch on the inverter; if the problem persists contact customer assistance.
  • If the problem has occurred after installation or after an inverter maintenance phase (therefore the cover has NOT been removed or the cable glands have NOT been acted upon), disconnect the AC grid and the DC input from the inverter and contact customer assistance.
– E084
– BackFeed OC
Yellow LED
Return current to photovoltaic field:
The error occurs if the input voltage is particularly low (typically in the evening in conditions of low irradiation) and indicates a return current from the inverter to the photovoltaic panels).
  • If the error occurs in the evening or in conditions of low irradiation, it must not be considered a problem but a protection intervention for the photovoltaic field.
    – If the problem occurs with good irradiation conditions, switch the inverter off and back on again; if the error persists, contact customer assistance.
– E089
– Wrong Wiring
Yellow LED
Incorrect grid wiring connection on Stand Alone:
The error occurs if the grid cables have been incorrectly connected to the Stand Alone output.
  • Check that the cables on the Stand Alone output have been installed correctly.

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