Chuẩn đoán kỹ thuật inverter Growatt – phần 1

Tài liệu này áp dụng cho các Inverter Growatt, 1 pha, các model từ Growatt1000S -> 5000MTLS, các lỗi: AC V Outrange, AC F Outrange, No AC Connection, Residual I High, PV Isolation Low, Output High DCI, Module Hot

The inverter will display a fault message on the LCD with the LED indicator turning red in case there is any system abnormal or inverter abnormal occurrence. All faults will stop the inverter feeding power to public grid immediately and wait until the fault is cleared.

In general, the operator should respond to the fault as follows:

1. The cause of the fault should be sought by referring to appropriate chart below.
2. If the problem cannot be rectified, please contact Growatt for assistance.

1. AC V Outrange

Possible cause: The grid voltage is out of permitted range, or the inverter’s voltage limits is incorrect.
If there are several inverters in parallel, and one or more inverters show “AC V Outrange” after the inverters feed electricity to grid for a while, this might be caused by high impedance between the inverter and feed-in point, please record the AC cables wiring condition and record the phenomenon, then contact Growatt service.
If the inverter shows “AC V Outrange” when turn on AC breaker, check following the steps below:

a. Turn off the AC breaker and DC switch, check whether the AC cables are connected properly;

b. Turn on AC breaker, measure the voltage between L and N on the AC terminal block using a multi-meter, if value exceeds the permitted limitation of your local regulation, please contact your local grid company to confirm the power quality of the grid;

c. Turn on DC switch, compare the grid voltage measured by multi-meter, and the AC voltage displayed on the inverter. If the tolerance is more than 3V, please calibrate the detected AC voltage of the inverter by following steps:

² Connect the inverter to PC via USB to RS232 cable.
² Open the software, Shine Bus to calibrate AC voltage limits as following steps:
1) Choose “4 Parameter” tab, select “Read” option as following figure.

2) Select 13, 14, 17 and 18 option in “Set ID” drop-down list, and click “Operate” button to read the AC voltage limits in “Set value” field one by one.

1. Check whether the limits are complied with local grid standard. If not, please reset the limits by Shine Bus. Fill corresponding value in “Set value” field, not selected “Read” option, and click the “Operate” button to set AC voltage limits one by one. Example as follow figure, related values refer to Table 1

2. If all conditions are OK and this fault still exists, please contact Growatt service.

2. AC F Outrange

Possible cause: The grid frequency is out of permitted range, or the inverter’s frequency limits is incorrect.
If there are multiple inverters running in parallel, and one or more inverters show “AC F Outrange” after connected to the grid, perhaps the impedance to the grid is too high, please record the AC cables wiring condition and record the phenomenon, then contact Growatt service.
If the inverter shows “AC F Outrange” when the AC breaker is turned on, check by following steps:
a. Check whether the frequency on the LCD is within the local grid standards, if not, please contact local electricity company.

Check the grid frequency limits by ShineBus as following steps:
1) Select layout “4 Parameter”, select option “Read” as following figure.

2) Select 15, 16, 19 and 20 option in “Set ID” drop-down list. And click button “Operate” to read the frequency limits one by one

1. Check whether the limits are complied with local grid standards. If not, please reset the limits by ShineBus. Fill Corresponding values in “Set value” field, not selected option “Read”, and click button “Operate” to set AC frequency limits one by one. Example as Fig.9, related values refer to Table 2.

2. If all conditions are OK and this fault still exists, please contact Growatt service.

3. No AC Connection
Possible cause: There is something wrong with the connection between grid and the inverter.
a. Check whether AC circuit breaker is off.
b. Check whether AC cables are all firmly and correctly connected.

c. Measure the voltage between the “L” and “N” terminal to check whether public grid is cut off.
d. If the fault is sustained, please contact Growatt service department for solution.

4. Residual I High
Possible cause: The residual current of the inverter detected is too high.
a. When inverter showing Residual I High, please restart the inverter 2 or 3 times.
b. If the error still exists, please examine if the live wire and neutral wire (L and N) are connected well.

c. If both the live wire and neutral wire (L and N) are wired correctly and firmly, but the error still exists, please contact the service center to replace the inverter.

5. PV Isolation Low
Possible cause: The impedance between the DC positive (PV+) to Ground or DC negative (PV-) to Ground is too low.
a. Check whether the PV modules are well grounded.
b. Check whether the inverter is well grounded.
c. Open the inverter cover to check if the inside grounding cable is well connected;
Note: Must authorized by Growatt to open the inverter casing in advance. Otherwise the warranty is void, according to Growatt factory warranty conditions.

d. Check if the marked screw is loose or not. If loose, please tighten it.

e. If the error still exists as the above checking is ok, please contact Growatt service.

6. Output High DCI 
Possible cause: The DC offset in the AC current is detected too high.
a. Please restart the inverter and check whether the fault still exists or not. If the fault doesn’t always appear, please don’t care because the inverter will automatically recover and continue working.
b. If the error appears much too often, please contact your installer to replace the inverter.

7. Module Hot
Possible cause: The inverter module is over heat.
a. Check whether the environment temperature is too high, try to lower it.
b. Something is wrong with the heat sensor, please replace it with a new one.