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Installation and Operation Manual for Solar Power Inverter M70A EU V2.0 EN 2020-08-03
9 Error events and troubleshooting
Faults
9.3 Faults
Fault num-
ber
Message
Possible causes
Suggestions for resolution
F01, F02,
F03
HW DC Injection
The grid waveform is abnormal.
Contact Delta Customer Service.
Internal error.
Contact Delta Customer Service.
F05
Temperature High
The ambient temperature is > 60 °C.
Check the system environment.
F06,
F08,
F09,
F10
HW NTC1 Fail,
HW NTC2 Fail,
HW NTC3 Fail,
HW NTC4 Fail
The ambient temperature is > 90 °C or < -30 °C. Check the system environment.
Detection circuit malfunction.
Contact Delta Customer Service.
F07
Temperature Low
The ambient temperature is < -30 °C.
Check the system environment.
Internal error.
Contact Delta Customer Service.
F13, F29
Relay Open
Internal error.
Contact Delta Customer Service.
F15,
F16,
F17
HW DSP ADC1,
HW DSP ADC2,
HW DSP ADC3
The DC input voltage is less than the minimum
required DC input voltage.
Check the DC input voltage on the inverter dis-
play.
There may be insufficient solar radiation.
Internal error.
Contact Delta Customer Service.
F18,
F19
HW Red ADC1,
HW Red ADC2
The DC input voltage is less than the minimum
required DC input voltage.
Check the DC input voltage on the inverter dis-
play.
There may be insufficient solar radiation.
Internal error.
Contact Delta Customer Service.
F20
HW Efficiency
Incorrect calibration.
Check the accuracy of the voltage and power.
Internal error.
Contact Delta Customer Service.
F22
HW COMM2
Internal error.
Contact Delta Customer Service.
F23
HW COMM1
Internal error.
Contact Delta Customer Service.
F24
Ground Current
Insulation fault in the PV system.
Check the insulation of the DC inputs.
Large PV system capacitance between Plus
and Ground or Minus and Ground.
Check the capacitance, it must be < 12 µF.
Install an external transformer if necessary.
Internal error.
Contact Delta Customer Service.
F26
HW Connect Fail
Internal error.
Contact Delta Customer Service.
F27
RCMU Fail
Internal error.
Contact Delta Customer Service.
F28
Relay Short
Internal error.
Contact Delta Customer Service.
Fault in the relay driver circuit.
Contact Delta Customer Service.
F30
Bus Imbalance
Incomplete independent or parallel configuration
between the inputs.
Check the input connections.
Grounding of the PV system.
Check the insulation of the PV system.
Internal error.
Contact Delta Customer Service.
F31, F33,
F35
HW Bus OVR
The DC input voltage is greater than the maxi-
mum permissible DC input voltage.
Change the solar system setting so that the
DC input voltage at DC1 is below the maximum
permissible DC input voltage.
Overvoltage during operation.
Contact Delta Customer Service.
Internal error.
Contact Delta Customer Service.
