Dyness Fault Codes

Inverters

Fault Name

Grid Loss

Solution

1.The alarm is automatically cleared after the grid
power supply is restored.
2.Check whether the AC cable is connected and
the AC breaker is on.

Fault Name

Grid voltage fault

Solution

Cause: 

Grid voltage exceeds allowable range
(undervoltage/overvoltage/VRT). The inverter
automatically returns to normal operation after
detecting that the power grid is normal.
Solutions:
1.If the problem occurs frequently, check whether
the grid voltage is within the permissible range.
2.Check grid voltage compliance. If unstable,
configure BACK-UP as EPS mode.
3.Enable high-impedance mode if voltage
fluctuates severely at remote installations.

Fault Name

Grid
frequency
fault

Solution

Cause: Grid frequency exceeds allowable range
(under/over frequency).
The inverter automatically returns to normal
operation after detecting that the power grid is
normal.

Solutions:
Verify grid frequency compliance. Contact the
utility company to adjust protection thresholds if

Fault Name

Grid phase angle fault

Solution

Cause: Grid voltage phase angle deviation. Rare
occurrence. The inverter automatically returns to
normal operation after detecting that the power
grid is normal.
Solutions:
Contact service provider if persistent.

Fault Name

Grid phase sequence fault

Solution

Cause:

Incorrect phase sequence (non-positive
sequence).

Solutions:
1. Enable phase sequence auto-adaptation
(default: enabled).
2. Verify grid terminal wiring sequence.

Fault Name

AC current has a high DC component

Solution

Cause:

The problem is caused by an external fault
like a utility grid exception or frequency
exception, the inverter will recover automatically
after solving the problem.

Solutions:
1.If the problem occurs frequently contact the
dealer or the after-sales service.
2.If it persists and cannot be recovered, it may be
a sensor malfunction, please contact the service
provider for confirmation.

Fault Name

Off-grid AC voltage has a high DC component

Solution

Cause:

Generally caused by half-wave load, it can
automatically restore normal operation.

Solutions:

1. Check load types (avoid half-wave load).
2. If it persists and cannot be recovered, it may be
a sensor malfunction, please contact the service
provider for confirmation

Fault Name

N-PE relay fault

Solution

Cause: Generally caused by poor grounding, stop
after two consecutive tests, you need to manually
clear.

Solutions:
1. Ensure proper grounding.
2. Disable N-PE relay via Inverter config if
externally shorted.
3. If the fault persists, the relay may be faulty.
Contact the service provider for confirmation.

Fault Name

BACK-UP output fault (overload, overcurrent, undervoltage)

Solution

Cause:

Overloaded BACK-UP port or insufficient
battery discharge capability.

Solutions:
1. Optimize BACK-UP load configuration.
2. Verify battery and load compatibility.

Fault Name

The inverter temperature is too high

Solution

Cause: High operating temperature

Solutions:
1. Ensure adequate airflow and avoid direct
sunlight.
2. If it persists and cannot be recovered, it may be
a sensor malfunction, please contact the service
provider for confirmation

Fault Name

The battery or PV input voltage is too high

Solution

Cause: 

PV string or battery voltage exceeds
specifications.

Solutions:
1. Please check the number of PV strings to
ensure that the maximum open circuit voltage
does not exceed the inverter operating voltage
range.
2. Check the battery specifications to ensure that
the maximum battery voltage does not exceed the
inverter operating voltage range.

Fault Name

BUS voltage is too high

Solution

Cause: The DC bus voltage of the inverter is out of
the working range, usually because the input
voltage of PV strings is too high or the external
environment changes dramatically leading to the
control failure, the inverter will automatically
recover when it detects that the bus voltage is
restored to the working range.

Solutions:
1. If it happens frequently, please check the
number of PV strings to make sure the maximum
open circuit voltage does not exceed the inverter
working voltage range.
2. If it is always there and cannot be recovered,
please contact the service provider for
confirmation.

Fault Name

Internal memory operation failure

Solution

Cause: Flash memory failure.

Solutions:
Replace flash memory if reboot fails, please
contact the service provider for confirmation.

Fault Name

CPLD communication loss

Solution

Cause: Internal logic chip failure.

Solutions:
Replace CPLD if reboot fails, please contact the
service provider for confirmation.

Fault Name

Slave DSP communication loss

Solution

Cause: Firmware upgrade failure or chip damage.
Solutions:
1. Retry firmware upgrade.
2. Replace DSP chip if unresolved, please contact provider

Fault Name

ARM communication loss

Solution

Cause: Communication failure between ARM and
DSP.
Solutions:
1. Retry firmware upgrade.
2. Contact service provider.

Fault Name

Abnormal battery access

Solution

Cause: Battery ready function not purchased or
hardware mismatch.

Solutions:
1. Remove battery if function is disabled.
2. Contact service provider for standard models.

Fault Name

Abnormal battery access

Solution

Cause: Battery ready function not purchased or
hardware mismatch.

Solutions:
1. Remove battery if function is disabled.
2. Contact service provider for standard models.

Fault Name

The insulation resistance is low

Solution

Cause:

System insulation below safety threshold.
Solutions:
1. Check PV/battery insulation for damage. For
example, the wiring harness is damaged or the
component shell is damaged.
2. Isolate components to diagnose.
3. Contact service provider.

Fault Name

GFCI protection

Solution

Cause: System leakage current exceeds limit.
After the fault disappears, the inverter
automatically returns to normal operation.
Solutions:
1. Inspect system components and grounding.
2.If the fault persists, the sensor may be faulty.
Contact the service provider for confirmation.

Fault Name

Reference voltage fault

Solution

Cause: Control board reference voltage failure.
Solutions:
Replace hardware if reboot fails, please contact
the service provider for confirmation.

Fault Name

AC relay fault

Solution

Cause: Inverter AC terminal relay self-test fails,
two consecutive self-test failures stop operation,
need to manually recover.
Solutions:
1. If it happens frequently, please check whether
there is poor contact or empty connection in the
inverter grid port wiring.
2. If the fault described in 1 is rectified and the
relay cannot be recovered after restart, contact
the service provider for confirmation.

Fault Name

Relay self-test fault

Solution

Cause: The inverter AC terminal relay fails the
single self-test, the inverter will automatically
re-test and resume operation after it passes.
Solutions:
If it happens frequently, please check whether the wiring of inverter grid port has poor contact or
empty connection.

Fault Name

HCT fault

Solution

Cause: Inverter current sensor failure, stop
running, need to restart manually to recover.
Solutions:
If it can not be restored after reboot, it may be
the inverter sensor failure, please contact the
service provider for confirmation.

Fault Name

HCT self-test fault

Solution

Cause: Inverter current sensor self-test failure,
the inverter will automatically re-test and resume
operation after it passes.
Solutions:
If it happens frequently, please contact the service
provider for confirmation.

Fault Name

GFCI self-test fault

Solution

Cause: Inverter GFCI device failure, stop running,
need to restart manually to recover.
Solutions:
If it can not be restored after reboot, it may be
the inverter sensor failure, please contact the
service provider for confirmation.

Fault Name

GFCI once
self-test fault

Solution

Cause: Inverter GFCI self-test failure, the inverter
will automatically re-test and resume operation
after it passes.
Solutions:
If it happens frequently, please contact the service
provider for confirmation.

Fault Name

PV Connect reverse fault

Solution

Cause: PV string polarity reversed.
Solutions:
Correct PV polarity.

Fault Name

Battery reverse connection

Solution

Cause: Battery polarity reversed.
Solutions:
Correct battery polarity