Skip to content
首页 » GROWATT INVENTER Frequently Asked Questions

GROWATT INVENTER Frequently Asked Questions

1.Error 117 reconnection Error 117


Inverter keep reconnecting, may caused by electric relay’s problem, may also caused by lack of solar panels, may lead in the morning and evening when there is no enough sunshine, the inverter can not connect to public grid and keep counting down, eventually report Error 117.


Based on different models inverter connected to the public grid, check if the panel number is too small, for the voltage is150V models it needs at least five panels, for the 350V on-grid models the panels should be not less than 12, you can turn off the DC input, restart the inverter to see if this error is still there.

2.DC arc discharging


Arc discharging maybe cause leakage of current, may cause by hot plug, the inverter or positive and negative poles short circled, wrong connection of positive and negative poles, unbalance panel numbers.


Check the inverter if it is properly shut down,otherwise if it is in working condition it will make current input cause arcdischarging.

Check the string if has positive negative short circle, check the string’s negative and positive poles in wrong connection,wrong connection string connect the same MPPT with right connection string will cause arc discharging.

Different connected size panels strings in the same MPPT may caused partial current to another string to the others, and cause arc discharging.

3.Loss connection of APP


Sensor and inverter are not connected

sensor has no power

APP scanned the inverter serial number

Installation signal problem

Faulty sensor


Check 232 port’s dial number switch is on

Check 232 port connected to the sensor.

Check 232 port communication is working.

Scan sensor’s serial number or type in the serial number and checkingcode.

Check the installation position, wrong installation position may cause signal loss, or WIFI Dongle cannot receive the router’s signal, GRPS card may be installed wrong position which cannot receive the signal.

Observing the sensor’s flashing, if there is no problem for outside condition, and sensor does not have any reaction, we can think it is a faulty sensor.

4.PV low voltage


PV voltage low means the string’s voltage is low,may cause being wrong positive, negative connection, loose connection, or no connection of the panels.


Need to set multimeter to voltage, use the red pen to connect to positive electrode, use the black pen to connect to negative electrode, read the multimeter, if the voltage is in voltage range and it is positive, we can say the PV voltage is normal.

5.PV high voltage


Different inverters have different DC input voltage range, so the connected solar panels would be set based on input DC voltage, basically “PV high voltage ” is caused by connection of too many panels.


Check the inverter’s setting, DC input voltage range, then check the string’s open circuit voltage.

6.Low insulation resistance


inverter has a function which can test DCinsulation resistance, check if the DC side is lower than 50kΩ, it will give analarm as “PV insulation low” may be cause by damaged DC cable, wet exposed cable, DC components electricityleakage, inverter DC side short circled on the ground


disconnect AC air breaker and DC air breaker.

Use MC spanner to dissemble DC side positive andnegative electrode.

Make sure the racks have ground connection(Essential)

(Use the multimeter set to resistance, use the red pen to test positive electrode, black pen to test the ground connection, read each way’s positive to ground’s resistance) (then use the red pen to connect to negative electrode and read the resistance between negative electrode and ground, if it is larger than 50kΩ then may think the inverter can judge thestring’s insulation, if the number is less or equal to 50kΩ, then the inverter’s insulation is down, the inverter will automatically to self protection and stop working, give the error as “low insulation resistance”).

7.High public grid voltage


grid voltage is exceeding inverter voltage range,normally is exceeding the highest setting voltage(factory setting is from195Vac-253Vac)

For General residential power plants, once the clients cannot use all the solar energy, the rest will be put to grid, as the resistance is very high, that may cause the output side of inverter, high voltage will lead to inverter offline.


use large input cable, as the larger cable is the smaller resistance.

Inverter is closer to grid, shorter cables and less resistance.

Change the resistance rate, copper has less resistance rate than aluminum, so generally use copper cable.

If the inverter is connected to agriculture grid which has higher voltage than inverter’s voltage limit, you can slightly adjust the voltage limit.

8.No public grid access


When AC side is down, it may cause inverter no finding of grid voltage.


Dissemble the output port of inverter, use a multimeter to find out if the voltage between live line and neutral line is 220V, if not, we can assume there is no problem with inverter, and outside AC side, you need to test the air breaker, disconnecting link, overvoltage protection and things like that.

9.Low power generatio


Low power generation can be caused by many reasons, weather, temperature, shade, inverters, panels orientation, panel angles and so on.


Weather: fog, rain, cloud, bad weather cancause low power generation.

high or low temperature can reduce the panel’s efficiency, and lower the power generation.

should check the site environment first, including trees, power pole,water tank, clothes, bird droppings, front panels covers back panels, one of the character of panels is once one panel covered, it will lower the whole system’s efficiency.

Panel orientation: check if the orientation is the best angle, the highest solar generation point is from 11:00AM to 2:00 PM.

different solar panels can not be connected to the same string and same MPPT, please notice a broken panel can significantly lower whole system’s power generation, please change broken panels immediately.

once the inverter is down it will not generate any power, please check the DC voltage,which is set to inverter’s voltage range.

Grid fluctuation can happen frequently, reliablegrid quality is one essential condition to ensure inverter working smoothly, soplease notice the grid fluctuation, frequency fluctuation may all effect the inverter’s power generation, even can cause inverter error, also nearby high power consumption can affect the inverter’s power generation.

10.When there is totally no AC present, inverter displays “AC V Outrange”, instead of display “No AC Connection”?

Growatt TL and MTL series inverters will display a “No AC Connection” message when the AC grid has lost, and showing “AC V Outrange” when the AC grid voltage is out of the permitted range. However, the UE series inverters changed slightly, it only displays “AC V Outrange” on its LCD, either the AC grid has totally lost, or AC grid voltage is out of the permitted range.

11.The knock control panel is not sensitive, it is not convenience to operate. Can I make it more sensitive?

This phenomenon is normal. In order to avoid any misoperation caused by surrounding noise, we adjusted the sensitive of knock control function. Furthermore, we added a “LOCK” to prevent any misoperation for Growatt UE series inverters. We can not change the sensitive of it.

12.What is the meaning of TL, MTL?

TL means “Transformerless”, the design without transformer internally is the leading-edge technology. It reduced weight of inverter, whereas increased the DC-to-AC convertion efficiency. MTL means “Multi MPP Tracker”. Inverter with more than one tracker can provide more flexible system design, for example, strings face to different directions, it is helpful when there is limit roof space for panels. Flexible system design / panel configuration helped to increase the system’s annual yield. Note: please make sure to connect strings to Tracker A and Tracker B separately, if the strings face to different directions.

13.What’s the meaning of “PV: xxx / xxx, B: xxx v” display on LCD screen, are those DC voltage for each PV string?

PV: xxx / xxx are the DC voltage from PV panel. For Growatt 2 MPPT machine (Growatt3600MTL, Growatt4200MTL, Growatt5000MTL), it indicate DC voltage of each MPPT. For 1 MPPT machine (Sungold1500, Sungold2000, Sungold3000, Sungold5000, Growatt1500, Growatt2000, Growatt3000, Growatt4400, Growatt5000), it will display as PV: xxx / 0. B: xxx v indicate the bus voltage in inverter’s boost circuit bus line.

14.How can I connect my inverters to computer via RS485?

Step 1: Connect inverters parallel by RS485 socket, make sure that Pin1 to Pin1 and Pin2 to Pin2.

Step 2: Connect one inverter to the computer via RS-485. A RS485-to-RS232 is needed.

Step 3: Set ShineNet software to communicate by Serial Port.

15.Why can’t I connect inverter via RS232 or RS485?

Please check your RS232 wire is connected directly, the cable length is recommended less than 25m. Make sure cable is working and functioning correctly. If doesn’t, should change the cable. Some serial adapters can cause communication problems. Try using another computer or laptop for testing. If you have access to a serial port loopback tester / analyzer, use that to confirm that there is no problem with the port / cable. Finishing the cable. Most cables are adequate up to 15 meters. If you have a long cable, do NOT coil it, as it can increase capacitance, and then corrupt data. If it passes close to many electrical cables, or inductor motors, such as washing machines and refrigerators, they can also cause interference. We suggest you limit the cable to 15 meters. If you are using a RS232-to-USB converter, make sure the driver had been installed properly. Check the serial port status and COM number in Device Management->Port (COM and LPT). In addition, watch screen of the inverter to make sure inverter’s COM address had been set to “COM Address: xx” (Fixed address, example, COM Address: 01)

16.Do you have free solution for monitoring?

Answer: ShineNet is an inverter monitoring software run in Windows XP, Windows Vista, Windows 7 operating system. It can monitor inverter via RS232 (or RS232 convert to USB cable) and RS485 wire connection. Customers can purchase the cable locally to get the inverter monitored, it is simple.

17.Does Growatt have monitoring solutions for plant scale system?

Answer: We provide a smart device named Shine Webbox. This is a monitoring device specially for plant scale systems. It can monitor maximum 32 units in specified condition (via RS485), and maximum 15 units wirelessly at the same time (via ZigBee module). Shine Webbox has integrated a network server, customers can browse monitored data easily in local area network. It also can upload monitored data to Internet (ShineServer) so customers can access to the data when travel worldwide. For more information about the above device, please refer to “Product” web page.

18.Does Growatt have monitoring solutions for residential system?

Answer: For small rating system, we have wired two monitoring solution (ShineNet via RS232 or RS485). a)Local wireless monitoring solution (ShineVision via RF module communication) b)Global wireless monitoring solution (WiFi Module via WiFi network). The WiFi Module can talk to customer’s residential router and upload monitored data to Internet based ShineServer, thus customers can browse the data in wherever there is Internet access service.

19.Is there other kind of software that customers can use to design a system for Growatt inverters?

Answer: Valentin PVSOL is a very popular PV system design software in Europe. The lastest software integrated Growatt inverters parameters, users can download the software from its website.

20.Are there any design tool and how to use ShineDesign?

Answer: ShineDesign is the system design software just for Growatt inverters. It can conduct installers to figure out panel numbers for a system, panel numbers for each string, and which inverter model is suitable for the system. Moreover, it can print a design report after input all necessary parameters, can calculate DC/AC wire wastage, annual generation, etc. Users can click “Download” on the website to get the software and user manual. Follow the manual everyone can design easily by himself.

Leave a Reply

Your email address will not be published. Required fields are marked *

💬Hi Need Any help?