Copy of PARALLELING INVERTERS

You can connect up to 16 inverters in parallel ( 15 on 3 Phase ) that will give your 150 kw Hybrid system


To configure multi-inverter settings, click on the 'Advance' icon.


For stability, all the batteries need to be connected in parallel. It is recommended that a minimum cable size is of 50mm diameter with fuse isolators to each inverter. When connecting inverters in parallel, there are some important points that you must remember:

  1. 1) You can only connect the 'GRID' input and 'LOAD' output in parallel.

  2. 2) Do not connect the 'AUX/Gen' input in parallel. This input can be used for Aux / Smart Load if required, but it is generally better not to use.

  3. 3) Ensure there is a good communication cable between each inverter and always set the Master Inverter centrally.




  1. 1) All batteries must be in parallel.

  2. 2) Inverters operating without batteries are only in Grid Operation, so they do not need to be paralleled in the same way.

  3. 3) You only need one CT coil per master.

  4. 4) Only the master can communicate with the battery array. However, suppose you are using more batteries than the number allowable for the inverter. In that case, the other batteries can be connected to the other inverters set to voltage only, and therefore there is no need for communication.

  5. 5) If the inverters are connected to the communication of the same battery array, the master will control the charges in the other inverters.




  1. 6) When connected to a generator, do not connect the communication cable if you are using the inverter as a charger. Consider it as a standalone inverter.

  2. 7) If using a single-phase, you only have one master and one CT coil.

  3. 8) If using three-phase, you need three masters and three CT coils.

  4. 9) Remember that each inverted needs its own data logger.

  5. 10) All inverters must be identical, so do not mix up types or software.

  6. 11) If you are unsure about the installation, please double-check with Sunsynk and check if you have the latest operating system. It is worth it carrying out an upgrade before you complete the final installation.

  7. 12) The most common problem with wiring inverters in parallel is the Communication Cable F29 Error. If using more than 3 inverters in parallel, you need to remove the resistors on the communication ports.

You can do this via a small dip switch located close to the parallel input,



SINGLE-PHASE CONFIGURATION the the 1) 2) 3) 4) 5) 6) 7) 8) 9) In theory, you can connect up to 16 inverters on a single-phase configuration, but be very careful about inrush current when switching on. You may need to add an additional contactor. The single-phase configuration only requires one master, and all the others are slaves. In addition, keep communication cable as short as possible. Check if all inverters have the same operating system and the latest software version and are the same model. On the multi-inverter page, select 'parallel' and choose the master, which is normally the central inverter. Ensure that you have good quality communication cable between the inverters. Set all the other inverters to be slaves. Each inverter needs its own unique MODBUS number. Each inverter needs its own data logger. You only need one CT coil, which is connected to the master. All batteries are wired in parallel. The master is the only one that communicates with the battery BMS. After checking and setting all this, you are good to go. As previously mentioned, the most common fault is a communication error between the inverters. Please study the previous Section 7 of this training manual.



7.2. THREE-PHASE CONFIGURATION The Sunsynk Hybrid Inverter can also be paralleled in a three-phase system with perfect phase rotation. In this case, you need to have three masters, and all the others are slaves. DO NOT forget that each inverter still needs its own unique MODBUS communication number. ◼ Phase A: Master A and Slave A ◼ Phase B: Master B and Slave B ◼ Phase C: Master C and Slave C

  1. 1) Check if all inverters have the same operating system and the latest software version and are the same model.

  2. 2) On the multi inverter page, select 'parallel' and choose the master, which is normally the central inverter.

  3. 3) Ensure that you have good quality communication cable between the inverters.

  4. 4) Set all the other inverters to be slaves

  5. 5) Each inverter needs its own unique MODBUS number.

  6. 6) Each inverter needs its own data logger.

  7. 7) You only need one CT coil, which is connected to the master.

  8. 8) All batteries are wired in parallel.

  9. 9) The master is the only one that communicates with the battery BMS.




It is possible to build a much larger system using many inverters, however, you need to split the loads, which is a good idea. A large system can have a common battery bank, so the solar array charges the same battery. Something to remember is that the inverters go through very stringent tests at our factory. They are tested for everything, as well as long soak tests. When the inverter leaves the factory, it is working perfectly. Therefore, any faults that appear are probably caused by installation issues. To check fault codes, click on the ‘Fault Codes’ icon on the settings menu.



I published this youtube video last year, how to wire 6 inverters in parallel


I still receive many text and E mails about F29 Fault


Parallel communication cable fault This error is a very common fault when connecting inverters in parallel. Basically, it means that the communication cable is not working correctly. This problem can be caused by the wrong type of communication cable, wrong connection on the communication cable plugs, poor quality cable, or an incorrect setting on the inverter(s). Another cause can also be the in-line resistor is set incorrectly If you experience this fault, I suggest you follow these steps:

  1. 1) Switch off all inverters and reset them.

  2. 2) Check if each inverter has the correct and same operating system.

  3. 3) Check if the models are all the same.

  4. 4) Replace the communication cable with shorter cables. If possible, ensure that the middle inverter is the master and the other are slaves, which keeps the communication cable as short as possible.

  5. 5) Check if the port limiting resistors are set correctly.

  6. 6) Check if all your batteries are on the same bus bar.



Below is a short video explaining the programming and wiring issues of connecting inverters in 3 phase parallel configuration "Hope it helps "