First of all, you need to understand that in order to connect two solar inverters, you need to make sure that the output voltage, frequency and power of the two solar inverters have the same basic parameters.
For example, if the output voltage and frequency of two solar inverters connected in parallel are different, it will lead to loop current between the solar inverters, and this loop current phenomenon will not only greatly reduce the efficiency of the whole solar system, but also may cause irreversible damage to the solar inverter, reducing the service lifespan of the solar inverter.
After purchasing two solar inverters with the same specifications, you need to ensure the safety of the surrounding environment, it is recommended to connect the solar inverters in a ventilated and dry environment, which will have the least impact on the connection work, and at the same time, you should wear insulated gloves and goggles and other protective equipment, which can further improve the safety of the operation.
Then, you need to prepare tools related to the connection work, including wire strippers, insulating tape, screwdrivers and wrenches, etc., which will play a role in the subsequent connection work.
Finally, you need to consult the operation manual of the parallel solar inverter to ensure that your later connection work is carried out correctly, which can to a certain extent reduce the possibility of your improper operation and protect your life and property safety.
1.2.1 Connect the input of solar inverter
The input of each solar inverter is usually labeled with the positive and negative terminals of the solar panels (PV). Connect the positive and negative terminals of the solar energy to the corresponding positions of the solar inverter using the PV cable. Note that after the connection, you need to check that all the connections are very strong and no looseness occurs.
1.2.2 Connecting the output of the solar inverter
The output of the solar inverter includes the load, the grid and the solar battery, etc. There are corresponding terminals on the two solar inverters, using PV cables with the same specifications, one end is connected to the terminals of the solar inverter, and the other end is connected to the zero line and the fire line of the equipment corresponding to the terminals of the solar inverter, and the two solar inverters are all connected in the same way, so that the two solar inverters are completed. parallel connection.
1.2.3 Connecting parallel and current lines
There are parallel communication ports and current sharing ports on the solar inverters, you need to connect the two solar inverters using parallel lines (to keep the output voltage and frequency consistent) and current lines (to balance the output current between each inverter) respectively, and pay attention to connecting them to the corresponding terminals.
As an example, one end of the two parallel wires is connected to the parallel communication port of the first solar inverter, while the other end of the two parallel wires is connected to the parallel communication port of the second solar inverter, and the same is true for the current wire connection
1.2.4 Connect the communication lines
Connect one end of the communication cable (e.g. RS485 and CAN bus, etc.) to the WiFi/GPRS communication ports of each of the two solar inverters, and the other end to the central control unit, so that you can monitor the working status of the solar inverters in order to react in time in case of any problems with them.
Install the two solar inverters in the solar system in parallel, make sure that they are properly connected to each device, then you can close the circuit breaker on the solar inverters, so that the solar inverters can be put into operation, let the solar inverters work for a period of time, if the solar inverters are in a normal working condition, then it means that the solar inverters’ parallel work is successfully completed.
Before the parallel connection of solar inverters, you need to increase the corresponding overload protection in the solar energy system, the overload protection can cut off the current in time when any solar inverter fails, resulting in excessive current in the line, preventing the equipment in the solar energy system from receiving further damage.
Parallel connection of solar inverters may cause some impact on the power grid, so you should explain to the local power grid company before connecting the solar inverters, and you can only connect the work after they are sure that there is no problem, which ensures the compliance of your connection work, and also protects your safety to a certain extent.
The parallel connection and installation of solar inverter involves professional scope, if you choose to complete independently, it may increase the difficulty of your installation work, in order to consider the safety of your life and property, you can seek help from professional installers, so that both the safety of the installation process and the performance of the solar inverter after the connection are guaranteed.
Paralleling solar inverters can increase the total output power of the solar system to meet your demand for electricity, through the understanding of the specific practices of paralleling solar inverters, you can correctly complete the connection work, I believe that the connection of the solar inverters can better serve you.
