4KVA/5KVA Parallel Installation Guide

1. Introduction

This inverter can be used in parallel with two different operation modes:

1. Parallel operation in single phase with up to 6 units. The supported maximum output power is 24KW/30KVA.
2. Maximum six units work together to support three-phase equipment. Four units support one phase maximum. The supported maximum output power is 24KW/30KVA and one phase can be up to 16KW/20KVA.

NOTE: If this unit is bundled with share current cable and parallel cable, this inverter is default supported parallel operation. You may skip section 3. If not, please purchase parallel kit and install this unit by following instruction from professional technical personnel in local dealer.

2. Package Contents

In parallel kit, you will find the following items in the package:

• Parallel board
• Parallel communication cable
• Current sharing cable

Diagram shows three items: a parallel board with connectors, a parallel communication cable, and a current sharing cable.

3. Parallel board installation

This installation steps are only applied to 4K/5K models.

1. Step 1: Remove wire cover by unscrewing all screws ?.

   Diagram shows an inverter with screws being removed from its wire cover.

2. Step 2: Remove communication board by unscrewing two screws ?.

   Diagram shows the rear of the inverter with screws being removed near the communication board.

3. Step 3: Remove two screws ? and disconnect the 2-pin and 14-pin cables ?. Take out the board under the communication board.

   Diagram shows the communication board being removed, with 2-pin and 14-pin cables disconnected.

4. Step 4: Remove two screws ? to take out the cover of the parallel communication.

   Diagram shows screws being removed from a parallel communication cover.

5. Step 5: Install the new parallel board with 2 screws ? tightly.

   Diagram shows a new parallel board being installed with screws.

6. Step 6: Re-connect the 2-pin and 14-pin cables ? to their original positions.

   Diagram shows the 2-pin and 14-pin cables being reconnected to the parallel board and communication board.

7. Step 7: Put the communication board back to the unit.
8. Step 8: Put the wire cover back to the unit. Now the inverter is providing parallel operation function.

4. Mounting the Unit

When installing multiple units, please follow the chart below:

Diagram shows four inverters arranged horizontally with arrows indicating spacing: approximately 20 cm clearance on the sides and 50 cm clearance above and below each unit.

NOTE: For proper air circulation to dissipate heat, allow a clearance of approximately 20 cm to the side and approximately 50 cm above and below the unit. Be sure to install each unit on the same level.

5. Wiring Connection

The cable size of each inverter is shown below:

Recommended battery cable and terminal size for each inverter:

Diagram illustrates a ring terminal with labels for diameter (D) and length (L).

WARNING: Be sure the length of all battery cables is the same. Otherwise, there will be voltage difference between inverter and battery, causing parallel inverters not to work.

Recommended AC input and output cable size for each inverter:

You need to connect the cables of each inverter together. Take the battery cables for example: You need to use a connector or bus-bar as a joint to connect the battery cables together, and then connect to the battery terminal. The cable size used from the joint to the battery should be X times the cable size in the tables above, where “X” indicates the number of inverters connected in parallel. Regarding AC input and output, please also follow the same principle.

CAUTION!! Please install the breaker at the battery and AC input side. This will ensure the inverter can be securely disconnected during maintenance and fully protected from over current of battery or AC input. The recommended mounted location of the breakers is shown in the figures in 5-1 and 5-2.

Recommended breaker specification of battery for each inverter:

*If you want to use only one breaker at the battery side for the whole system, the rating of the breaker should be X times the current of 1 unit, where “X” indicates the number of inverters connected in parallel.

Recommended breaker specification of AC input with single phase:

Note 1: Also, you can use a 40A breaker (50A for 5KVA) for only 1 unit, and each inverter has a breaker at its AC input.

Note 2: Regarding three-phase system, you can use a 4-pole breaker; the rating is up to the current of the phase which has the maximum units. Or you can follow the suggestion of note 1.

Recommended battery capacity

WARNING! Be sure that all inverters will share the same battery bank. Otherwise, the inverters will transfer to fault mode.

5-1. Parallel Operation in Single phase

Two inverters in parallel:

Power Connection:

Diagram shows two inverters connected to BATTERY (red/black wires), Utility (blue/brown/dashed wires for L/N), and Load (blue/brown/dashed wires for L/N).

Communication Connection:

Diagram shows two inverters' communication ports (labeled 1 and 2) connected sequentially with green and red dotted lines.

Three inverters in parallel:

Power Connection:

Diagram shows three inverters connected to BATTERY, Utility, and Load, similar to the two-inverter setup but with an additional inverter.

Communication Connection:

Diagram shows three inverters' communication ports (labeled 1, 2, and 3) connected sequentially with green and red dotted lines.

Four inverters in parallel:

Power Connection:

Diagram shows four inverters connected to BATTERY, Utility, and Load.

Communication Connection:

Diagram shows four inverters' communication ports (labeled 1, 2, 3, and 4) connected sequentially with green and red dotted lines.

Five inverters in parallel:

Power Connection:

Diagram shows five inverters connected to BATTERY, Utility, and Load.

Communication Connection:

Diagram shows five inverters' communication ports (labeled 1, 2, 3, 4, and 5) connected sequentially with green and red dotted lines.

Six inverters in parallel:

Power Connection:

Diagram shows six inverters connected to BATTERY, Utility, and Load.

Communication Connection:

Diagram shows six inverters' communication ports (labeled 1, 2, 3, 4, 5, and 6) connected sequentially with green and red dotted lines.

5-2. Support 3-phase equipment

Two inverters in each phase:

Power Connection:

Diagram shows three sets of inverters (P1, P2, P3 representing phases L1, L2, L3) connected to BATTERY, Utility (L1, L2, L3, N), and Load (L1, L2, L3, N).

Communication Connection:

Diagram shows communication ports of inverters across three phases connected sequentially.

Four inverters in one phase and one inverter for the other two phases:

Power Connection:

Diagram shows a configuration with four inverters on one phase (e.g., P1) and one inverter on each of the other two phases (P2, P3), connected to BATTERY, Utility (L1, L2, L3, N), and Load (L1, L2, L3, N).

Communication Connection:

Diagram shows communication ports connected across the different phase groups.

Note: It's up to customer's demand to pick 4 inverters on any phase. P1: L1-phase, P2: L2-phase, P3: L3-phase.

Three inverters in one phase, two inverters in second phase and one inverter for the third phase:

Power Connection:

Diagram shows a three-phase configuration with three inverters on P1, two on P2, and one on P3, connected to BATTERY, Utility, and Load.

Communication Connection:

Diagram shows communication ports connected across the different phase groups.

Three inverters in one phase and only one inverter for the remaining two phases:

Power Connection:

Diagram shows a three-phase configuration with three inverters on P1, one on P2, and one on P3, connected to BATTERY, Utility, and Load.

Communication Connection:

Diagram shows communication ports connected across the different phase groups.

Two inverters in two phases and only one inverter for the remaining phase:

Power Connection:

Diagram shows a three-phase configuration with two inverters on P1, two on P2, and one on P3, connected to BATTERY, Utility, and Load.

Communication Connection:

Diagram shows communication ports connected across the different phase groups.

Two inverters in one phase and only one inverter for the remaining phases:

Power Connection:

Diagram shows a three-phase configuration with two inverters on P1, one on P2, and one on P3, connected to BATTERY, Utility, and Load.

Communication Connection:

Diagram shows communication ports connected across the different phase groups.

One inverter in each phase:

Power Connection:

Diagram shows a three-phase configuration with one inverter on P1, one on P2, and one on P3, connected to BATTERY, Utility, and Load.

Communication Connection:

Diagram shows communication ports connected across the different phase groups.

WARNING: Do not connect the current sharing cable between the inverters which are in different phases. Otherwise, it may damage the inverters.

6. PV Connection

Please refer to the user manual of a single unit for PV Connection.

CAUTION: Each inverter should connect to PV modules separately.

7. LCD Setting and Display

Setting Program:

Program 28 Description:

• When the units are used in parallel with single phase, please select “PAL” in program 28.
• It is required to have at least 3 inverters or maximum 6 inverters to support three-phase equipment. It's required to have at least one inverter in each phase or it's up to four inverters in one phase. Please refer to 5-2 for detailed information.
• Please select “3P1” in program 28 for the inverters connected to L1 phase, “3P2” in program 28 for the inverters connected to L2 phase, and “3P3” in program 28 for the inverters connected to L3 phase.
• Be sure to connect share current cable to units which are on the same phase. Do NOT connect share current cable between units on different phases.
• Besides, power saving function will be automatically disabled.

Program 30 Description:

• When "ONE" is selected, as long as one of the inverters has been connected to PV modules and PV input is normal, the parallel or 3-phase system will continue working according to the rule of “solar first" setting. For example, two units are connected in parallel and set “SOL” in output source priority. If one of the two units has connected to PV modules and PV input is normal, the parallel system will provide power to loads from solar or battery power. If both are not sufficient, the system will provide power to loads from utility.
• When "ALL" is selected, the parallel or 3-phase system will continue working according to the rule of "solar first" setting only when all of the inverters are connected to PV modules. For example, two units are connected in parallel and set “SOL” in output source priority. When selecting “ALL" in program 30, it's necessary to have all inverters connected to PV modules and PV input is normal to allow the system to provide power to loads from solar and battery power. Otherwise, the system will provide power to loads from utility.

Fault code display:

8. Commissioning

Parallel in single phase

Step 1: Check the following requirements before commissioning:

• Correct wire connection ✔️
• Ensure all breakers in Line wires of load side are open and each Neutral wires of each unit are connected together.

Step 2: Turn on each unit and set “PAL” in LCD setting program 28 of each unit. And then shut down all units.

NOET: It's necessary to turn off switch when setting LCD program. Otherwise, the setting can not be programmed.

Step 3: Turn on each unit.

LCD display in Master unit:

Diagram shows a simplified LCD screen with 'INPUT AC 0 V' and 'OUTPUT 85, 230 V'. Icons for AC input (lightning bolt), battery (battery symbol), and load (house symbol) are shown.

LCD display in Slave unit:

Diagram shows a simplified LCD screen with 'INPUT AC 0 V' and 'OUTPUT 54, 230 V'. Icons for AC input, battery, and load are shown.

NOTE: Master and slave units are randomly defined.

Step 4: Switch on all AC breakers of Line wires in AC input. It's better to have all inverters connect to utility at the same time. If not, it will display fault 82 in following-order inverters. However, these inverters will automatically restart. If detecting AC connection, they will work normally.

Diagram shows simplified LCD screens for Master and Slave units displaying 'INPUT AC 230 V' and 'OUTPUT 85, 230 V' (Master) or 'OUTPUT 54, 230 V' (Slave), with BYPASS and CHARGING indicators.

Step 5: If there is no more fault alarm, the parallel system is completely installed.

Step 6: Please switch on all breakers of Line wires in load side. This system will start to provide power to the load.

Support three-phase equipment

Step 1: Check the following requirements before commissioning:

• Correct wire connection ✔️
• Ensure all breakers in Line wires of load side are open and each Neutral wires of each unit are connected together.

Step 2: Turn on all units and configure LCD program 28 as P1, P2 and P3 sequentially. And then shut down all units.

NOET: It's necessary to turn off switch when setting LCD program. Otherwise, the setting can not be programmed.

Step 3: Turn on all units sequentially.

LCD display in L1-phase unit:

Diagram shows LCD screen: 'INPUT AC 0 V', 'OUTPUT 0 P1, 230 V'.

LCD display in L2-phase unit:

Diagram shows LCD screen: 'INPUT AC 0 V', 'OUTPUT 0 P2, 230 V'.

LCD display in L3-phase unit:

Diagram shows LCD screen: 'INPUT AC 0 V', 'OUTPUT 0 P3, 230 V'.

Step 4: Switch on all AC breakers of Line wires in AC input. If AC connection is detected and three phases are matched with unit setting, they will work normally. Otherwise, the AC icon will flash and they will not work in line mode.

Diagram shows LCD screens for L1, L2, L3 phase units displaying 'INPUT AC 230 V' and 'OUTPUT 230 P1, 230 V' (or P2, P3), with BYPASS and CHARGING indicators.

Step 5: If there is no more fault alarm, the system to support 3-phase equipment is completely installed.

Step 6: Please switch on all breakers of Line wires in load side. This system will start to provide power to the load.

Note 1: To avoid overload occurring, before turning on breakers in load side, it's better to have whole system in operation first.

Note 2: Transfer time for this operation exists. Power interruption may happen to critical devices, which cannot bear transfer time.

9. Trouble shooting