1. Introduction
This manual describes the assembly, installation, operation, and troubleshooting of this unit. Please read this manual carefully before installation and commissioning. Keep this manual for future reference.
This manual contains safety and installation guidelines, as well as information on tools and wiring.
1.1. Key Features
- Pure sine wave inverter.
- Programmable supply priority for PV, battery, or grid.
- High PV input voltage range (55~450VDC).
- Built-in MPPT solar charger with a maximum of 110A.
- Compatible with Lithium-ion batteries.
- Supports BMS communication with Lithium batteries.
- Overload, over-temperature, and short-circuit protection for the inverter output.
- Cold start function.
- Intelligent fan speed adjustment.
- Optional WiFi module for convenient real-time monitoring.
1.2. Basic System Architecture
The following diagram illustrates the basic application for this inverter/charger. It also includes the following devices to operate a complete system:
- Generator or power supply.
- PV modules (optional).
Consult your system integrator for other possible system architectures depending on your requirements. This inverter can power all types of devices at home or in the office, including motor-driven devices such as fluorescent lamps, fans, refrigerators, and air conditioners.
2. Safety Instructions
WARNING: This chapter contains important safety and operating instructions. Read this manual and keep it for future reference.
- Read all instructions and warning labels on the unit, batteries, and all appropriate sections of this manual before using the unit.
- CAUTION: To reduce the risk of injury, charge only deep-cycle lead-acid batteries. Other battery types may burst, causing injury and damage.
- Do not disassemble the unit. If maintenance or repair is required, take it to a qualified service center. Improper reassembly may result in electric shock or fire.
- To reduce the risk of electric shock, disconnect all cables before performing maintenance or cleaning. Turning off the unit does not reduce this risk.
- CAUTION: Only qualified personnel may install this unit with a battery.
- NEVER charge a frozen battery.
- For optimal operation of this inverter/charger, please observe the required information for selecting the appropriate cable size. It is very important to operate this inverter/charger correctly.
- Be very careful when working with metal tools on or near batteries. There is a risk that a dropped tool could spark or cause a short circuit in batteries or other electrical parts, which could lead to an explosion.
- Please strictly adhere to the installation procedure when disconnecting AC or DC connections. Details can be found in the INSTALLATION section of this manual.
- GROUNDING INSTRUCTIONS: This inverter/charger should be connected to a permanently grounded wiring system. When installing this inverter, ensure compliance with local requirements and regulations.
- NEVER short-circuit the AC output and DC input. DO NOT connect the unit to the grid if the DC input is short-circuited.
- Warning!!! This unit may only be serviced by qualified personnel. If the faults persist even after the troubleshooting table, send the inverter/charger to the local dealer or service center for service.
3. Setup
3.1. Unpacking and Inspection
Before installation, please check the unit. Make sure nothing in the package is damaged. The package should contain the following parts:
- Unit x 1
- User Manual x 1
3.2. Preparation
Before connecting all wires, please remove the bottom cover by unscrewing two screws as shown below.
3.3. Mounting the Unit
Observe the following points before choosing the installation location:
- Do not mount the inverter on flammable building materials.
- Mount on a solid surface.
- Install the inverter at eye level to view the LCD display.
- The ambient temperature should be between 0°C and 55°C.
- It is recommended to mount the unit vertically on the wall.
Ensure that other objects and surfaces are kept away to ensure adequate heat dissipation and sufficient space for cable removal.
SUITABLE FOR MOUNTING ON CONCRETE OR OTHER NON-COMBUSTIBLE SURFACES.
3.4. Battery Connection
CAUTION: For operational safety and compliance, it is necessary to install a separate DC overcurrent protection or a disconnect device between the battery and the inverter. In some applications, a disconnect device is not required, but overcurrent protection should be installed. Please refer to the typical amperage in the table below for the required fuse or circuit breaker size.
WARNING! All wiring must be performed by qualified personnel.
WARNING! For system safety and efficient operation, it is very important to use an appropriate cable for the battery connection. To reduce the risk of injury, please use the correct recommended cable and terminal size (see below).
Recommended battery cable and terminal size:
| Model | Wire Size Cable mm² | Ring Terminal Dimensions | Torque Value | |
|---|---|---|---|---|
| D (mm) | L (mm) | |||
| 3.8KW 24V / 6.2KW 48V | 1*2AWG 22 | 6.4 | 33.2 | 2 Nm |
| 3.8KW 48V | 1*4AWG 22 | 6.4 | 33.2 | 2 Nm |
Battery Connection Steps:
- Assemble the battery ring terminal according to the recommended battery cable and terminal size.
- Connect all battery packs as required by the units.
- Insert the battery cable ring terminal flat into the inverter's battery connector and ensure the screws are tightened to a torque of 2-3 Nm. Make sure the polarity is correct on both the battery and the inverter/charger, and that the ring terminals are securely screwed to the battery terminals.
WARNING: Shock hazard! Installation must be carried out carefully due to high battery voltage in series.
CAUTION!! Do not place any objects between the flat part of the inverter terminal and the ring terminal. Otherwise, overheating may occur.
CAUTION!! Do not apply antioxidant to the terminals before the terminals are securely connected.
CAUTION!!! Before making the final DC connection or closing the DC circuit breaker/disconnect switch, ensure that positive (+) is connected to positive (+) and negative (-) to negative (-).
3.5. AC Input/Output Connection
CAUTION!! Before connecting the inverter to the AC input power source, please install a separate AC circuit breaker between the inverter and the AC input power source. This ensures that the inverter can be safely disconnected during maintenance and is fully protected against overcurrent at the AC input. The recommended specification for the AC breaker is 32A for 3.8KW, 50A for 6.2KW.
CAUTION!! There are two terminal blocks labeled "IN" and "OUT". Do NOT insert the input and output connections incorrectly.
WARNING! All wiring must be performed by qualified personnel.
WARNING! For system safety and efficient operation, it is very important to use an appropriate cable for the AC input connection. To reduce the risk of injury, please use the recommended cable size specified below.
Recommended cable requirements for AC lines:
| Model | Gauge | Torque Value |
|---|---|---|
| 3.8KW | 12 AWG | 1.2~1.6 Nm |
| 6.2KW | 8 AWG | 1.4~1.6Nm |
AC Input/Output Connection Steps:
- Before making the AC input/output connection, you must first open the DC protection or disconnect switch.
- Remove 10mm of insulation sleeve for six conductors. Shorten phase L and neutral N by 3mm.
- Insert the AC input wires according to the polarity indicated on the terminal block and tighten the terminal screws, ensuring the protective earth (PE) conductor is connected first.
- Ground (yellow-green)
- L → LINE (brown or black)
- N → Neutral (blue)
WARNING: Make sure the AC power source is disconnected before attempting to connect it to the unit.
- Then insert the AC output wires according to the polarity indicated on the terminal block and tighten the terminal screws. Make sure to connect the protective earth (PE) conductor first.
- L → Line (brown or black)
- N → Neutral (blue)
- Make sure the cables are securely connected.
CAUTION: Important! Ensure that the AC lines are connected with the correct polarity. If the L and N wires are reversed, this can cause a short circuit when these inverters operate in parallel.
CAUTION: Devices such as air conditioners require at least 2-3 minutes to restart, as sufficient time is needed to equalize the refrigerant gas in the circuits. If a power outage occurs and is restored in a short time, this can damage the connected devices. To avoid this type of damage, please check before installation whether the air conditioner is equipped with a time delay function. Otherwise, the inverter/charger will trigger an overload fault and interrupt the power supply to protect your device, but sometimes this still leads to damage to the air conditioner.
3.6. PV Connection
CAUTION: Before connecting to the PV modules, a separate DC circuit breaker must be installed between the inverter and the PV modules.
WARNING! All wiring must be performed by qualified personnel.
WARNING! For system safety and efficient operation, it is very important to use an appropriate cable for connecting the PV modules. To reduce the risk of injury, please use the recommended cable size specified below.
Recommended cable requirements for PV modules:
| Model | Wire Size | Cable (mm²) | Torque value (max) |
|---|---|---|---|
| 3.8KW/6.2KW | 1x12AWG | 4 | 1.2 Nm |
PV Connection Steps:
- Remove 10mm of insulation sleeve for positive and negative conductors.
- Check the correct polarity of the connection cable from PV modules and PV input connectors. Then connect the positive pole (+) of the connection cable to the positive pole (+) of the PV input connector. Connect the negative pole (-) of the cable to the negative pole (-) of the PV input connector.
- Make sure the wires are securely connected.
3.7. Final Assembly
After connecting all cables, replace the bottom cover by screwing in two screws as shown below.
4. Operation
4.1. Power ON/OFF
Once the unit is properly installed and the batteries are well connected, simply press the On/Off switch (located on the side of the housing) to turn on the unit.
4.2. Operation and Display Panel
The operation and display panel, shown in the following table, is located on the front of the inverter. It contains three indicators, four function buttons, and an LCD display that shows the operating status and input/output power information.
LED Indicators:
| LED Indicator | Color | Message |
|---|---|---|
| AC/INV | Green | Solid On: Output is powered by utility in Line Mode. Flashing: Output is powered by battery or PV in Battery Mode. |
| CHG | Green | Solid On: Battery is fully charged. Flashing: Battery is charging. |
| FAULT | Red | Solid On: Inverter fault. Flashing: Warning condition occurs in the inverter. |
Function Buttons:
| Function Button | Description |
|---|---|
| ESC | To exit setting mode. |
| UP | To go to the previous selection. |
| DOWN | To go to the next selection. |
| ENTER | To confirm the selection in setting mode or enter setting mode. |
4.3. LCD Display Icons
The LCD display shows various information about the inverter's status and operation. This includes input source information, configuration programs, fault information, output information, and battery information.
Key LCD Display Information:
- Input Source Information: Displays AC input, PV input, input voltage, input frequency, PV voltage, battery voltage, and charging current.
- Configuration Program and Fault Information: Shows setting programs, warning and fault codes.
- Output Information: Displays output voltage, output frequency, load in percent, load in VA, load in watts, and discharge current.
- Battery Information: Shows battery capacity percentage (0-24%, 25-50%, 50-74%, 75-100%) and battery voltage status (e.g., <1.717V/cell, >2.033V/cell).
4.4. LCD Setting
After pressing and holding the ENTER button for three seconds, the unit enters setting mode. Press the "UP" or "DOWN" button to select setting programs. Then press the ENTER button to confirm the selection, or the ESC button to exit.
The manual provides detailed tables for various settings including output source priority, maximum charging current, battery equalization voltage, float charging voltage, and more. Please refer to the full PDF user manual for a complete list of LCD setting options and their values.
4.5. Operating Mode Description
The inverter operates in different modes depending on the power sources available and configured priorities.
Standby Mode / Power Saving Mode:
- Standby Mode: The inverter is not yet switched on, but at this point, the inverter can charge the battery without AC output.
- Power Saving Mode: When activated, the inverter output is switched off if the connected load is very low or not detected.
Line Mode:
The unit supplies output power from the grid. It also charges the battery in grid operation. If "SUB" is selected as the output source and solar energy is not sufficient to supply the load, solar energy and the utility supply the load and charge the battery simultaneously.
Battery Mode:
The unit supplies output power from the battery and PV power. The PV energy will supply power to the consumers and charge the battery simultaneously.
4.6. Battery Equalization Function
The equalization function is integrated into the charge controller. It reverses the build-up of negative chemical effects such as stratification, where the acid concentration at the bottom of the battery is higher than at the top. The equalization function also helps remove sulfate crystals that may have formed on the plates. If this condition, called sulfation, remains uncontrolled, the total capacity of the battery will decrease. It is therefore recommended to equalize the battery regularly.
How to apply the equalization function:
You must first activate the battery equalization function in LCD setting program 33. Then you can apply this function in the unit using one of the following methods:
- Setting the equalization interval in program 34.
- Immediate activation of the equalization function in program 39.
When is equalization performed?
In the float phase, when the set equalization interval (battery equalization cycle) is reached or equalization is immediately active, the controller starts the equalization stage.
Equalization Charging Time and Timeout:
In the equalization charging stage, the controller supplies current to fully charge the battery until the battery voltage rises to the equalization voltage. Then, constant voltage regulation is applied to maintain the battery voltage at the battery equalization voltage. The battery remains in the equalization stage until the set battery equalization time is reached.
However, if the battery equalization time has expired in the equalization stage and the battery voltage does not rise to the battery equalization voltage, the charge controller extends the battery equalization time until the battery voltage reaches the battery equalization voltage. If the battery voltage is still lower than the battery equalization voltage when the equalization time setting has expired, the charge controller ends the equalization and returns to the float phase.
4.7. Lithium Battery Display Interface
To enter the display interface for Lithium batteries:
- Press the ENTER button to enter the setting element and set element 05 to Lithium battery mode (Lb).
- Long press the ESC button to enter the Lithium battery display interface.
The initial display interface shows the total battery voltage and remaining battery capacity. Press the DOWN button to display the data sequentially:
- Total battery voltage
- Battery charging current
- Battery capacity
- BMS board temperature
- Maximum voltage of a single battery cell
- Minimum voltage of a single battery cell
- Maximum temperature of a single battery cell
- Minimum temperature of a single battery cell
5. Maintenance
Regular maintenance ensures the longevity and optimal performance of your DATOUBOSS inverter. Follow these general guidelines:
- Cleaning: Keep the inverter clean and free from dust and debris. Use a dry, soft cloth for cleaning. Do not use liquid cleaners.
- Ventilation: Ensure that the ventilation openings are not blocked to allow for proper airflow and heat dissipation.
- Cable Connections: Periodically check all cable connections (battery, AC input/output, PV) for tightness and corrosion. Loose connections can lead to poor performance or safety hazards.
- Battery Health: Monitor battery voltage and capacity regularly, especially if using lead-acid batteries, to ensure they are within optimal operating parameters. Perform battery equalization as needed.
- Environment: Ensure the inverter is operating within the recommended ambient temperature range (0°C to 55°C) and is not exposed to direct sunlight or excessive moisture.
- Firmware Updates: Check the manufacturer's website for any available firmware updates to ensure your inverter has the latest features and bug fixes.
6. Troubleshooting
This section provides information on common issues and their solutions. If the problem persists, contact a qualified service technician.
6.1. Fault Reference Codes
| Fault Code | Fault Event | Icon on |
|---|---|---|
| 01 | Fan is locked when the inverter is off. | E |
| 02 | Over temperature | 03- |
| 03 | Battery voltage is too high | 04- |
| 04 | Battery voltage is too low | 05- |
| 05 | A short circuit or over temperature at the output is detected by the internal components of the converter. | 06- |
| 06 | Output voltage is too high. | 07 |
| 07 | Overload time out | 08 |
| 08 | Bus voltage is too high | 09 |
| 09 | Bus soft start failed | 11 |
| 11 | Main relay failed | 51 |
| 51 | Overcurrent or overvoltage | 52 |
| 52 | Bus voltage is too low | 53- |
| 53 | Inverter soft start failed | 55- |
| 55 | Over DC voltage in AC output | 56- |
| 56 | Battery connection is open | 57- |
| 57 | Current sensor failed | 58 |
| 58 | Output voltage is too low |
6.2. Troubleshooting Table
| Problem | LCD/LED/Buzzer | Explanation / Possible cause | What to do |
|---|---|---|---|
| The unit switches off automatically during the start-up process. | LCD/LEDs and buzzer are active for 3 seconds and then turn off completely. | Battery voltage is too low (<1.91V/cell) | 1. Recharge the battery. 2. Replace the battery. |
| No reaction after switching on. | No indication. | 1. Battery voltage is too low (<1.4V/cell). 2. Battery is connected with reverse polarity. | 1. Check if batteries and wiring are correctly connected. 2. Recharge the battery. 3. Replace the battery. |
| Mains voltage present, but the unit operates in battery mode. | Input protection is triggered. | Check if the AC breaker and AC wiring are correctly connected. | 1. Check if the AC cables are too thin and/or too long. 2. Check if the generator (if applicable) is working properly or if the input voltage range is set correctly (UPS → Device). Change the output source priority to "Utility first". |
| The buzzer beeps continuously and the red LED lights up. | Fault code 07 | Overload fault. The inverter is overloaded by 110% and the time has expired. | Reduce the connected power by switching off some devices. |
| Fault code 05 | Output is short-circuited. | Check if the wiring is correctly connected and remove abnormal loads. | |
| Fault code 02 | The temperature of the internal converter component is above 120°C. | Check if the unit's airflow is blocked or if the ambient temperature is too high. | |
| Fault code 03 | Battery is overcharged. | Check if the battery specifications and quantity meet the requirements. | |
| Fault code 01 | Fan fault. | Replace the fan. | |
| Fault code 08/09/53/57 | Internal components have failed. | Return to the repair center. | |
| Fault code 51 | Overcurrent or overvoltage. | Restart the unit. If the fault occurs again, please send it to the repair center. | |
| Fault code 52 | Bus voltage is too low. | If the battery is well connected, please take it to the repair center. | |
| Fault code 55 | Output voltage is unbalanced. | Return to the repair center. | |
| Fault code 56 | The battery is not properly connected or the fuse is blown. | If the battery is well connected, please take it to the repair center. |
7. Specifications
7.1. Line Mode Specifications
| INVERTER MODEL | 3.8KW 24V | 3.8KW 48V | 6.2KW 48V |
|---|---|---|---|
| Waveform of input voltage | Sinusoidal (utility or generator) | ||
| Nominal input voltage | 230Vac | ||
| Low loss voltage | 170Vac±7V (UPS); 90Vac±7V (Appliances) | ||
| Low loss return voltage | 180Vac±7V (UPS); 100Vac±7V (Appliances) | ||
| High loss voltage | 280Vac±7V | ||
| High loss return voltage | 270Vac±7V | ||
| Maximum AC input voltage | 300Vac | ||
| Nominal input frequency | 50Hz/60Hz (Auto detection) | ||
| Low loss frequency | 40±1Hz | ||
| Low loss return frequency | 42±1Hz | ||
| High loss frequency | 65±1Hz | ||
| High loss return frequency | 63±1Hz | ||
| Output short circuit protection | Line mode: Circuit Breaker; Battery mode: Electronic Circuits | ||
| Efficiency (Line Mode) | >95% (Rated R load, battery full charged) | ||
| Transfer time | 10ms typical (UPS); 20ms typical (Appliances) | ||
| Output power derating: When the AC input voltage drops to 95V or 170V depending on the model, the output power is reduced. |  | ||
7.2. Inverter Mode Specifications
| INVERTER MODEL | 3.8KW 24V | 3.8KW 48V | 6.2KW 48V |
|---|---|---|---|
| Nominal power | 4.2KVA/3.8KW | 7.0KVA/6.2KW | |
| Output voltage waveform | Pure Sine Wave | ||
| Output voltage regulation | 230Vac ±5% | ||
| Output frequency | 60Hz or 50Hz | ||
| Peak efficiency | 94% | ||
| Overload protection | 5s@≥150% Load; 10s@110 %~150% Load | ||
| Overvoltage capacity | 2* Nominal power for five seconds | ||
| Nominal DC input voltage | 24Vdc | 48Vdc | |
| Cold start voltage | 23.0Vdc | 46.0Vdc | |
| Low DC warning voltage @ load<20% | 22.0Vdc | 44.0Vdc | |
| Low DC warning voltage @ 20%< load<50% | 21.4Vdc | 42.8Vdc | |
| Low DC warning voltage @ load ≥ 50% | 20.2Vdc | 40.4Vdc | |
| Low DC warning return voltage @ load<20% | 23.0Vdc | 46.0Vdc | |
| Low DC warning return voltage @ 20%< load<50% | 22.4Vdc | 44.8Vdc | |
| Low DC warning return voltage @ load ≥ 50% | 21.2Vdc | 42.4Vdc | |
| Low DC disconnect voltage @ load<20% | 21.0Vdc | 42.0Vdc | |
| Low DC disconnect voltage @ 20%< load<50% | 20.4Vdc | 40.8Vdc | |
| Low DC disconnect voltage @ load ≥ 50% | 19.2Vdc | 38.4Vdc | |
| High equalization voltage | 29Vdc | 58Vdc | |
| High DC disconnect voltage | 31Vdc | 62Vdc | |
| No load current consumption | <25W | <50W | |
| Power consumption in economy mode | <10W | <15W | |
7.3. Charge Mode Specifications
Utility Charging Mode:
| INVERTER MODEL | 3.8KW 24V | 3.8KW 48V | 6.2KW 48V |
|---|---|---|---|
| Charging current (UPS) @ nominal input voltage | 80A | 60A | 80A |
| Bulk charging voltage (Flooded Battery) | 29.2V | 58.4V | |
| Bulk charging voltage (AGM/Gel Battery) | 28.2V | 56.4V | |
| Float charging voltage | 27Vdc | 54Vdc | |
| Charging Algorithm | 3-Step | ||
Solar Charging Mode:
| INVERTER MODEL | 3.8KW 24V | 3.8KW 48V | 6.2KW 48V |
|---|---|---|---|
| Nominal power | 6000W | ||
| PV charging current | 110A | 80A | 110A |
| Efficiency | 98.0% max. | ||
| Max. PV Array Open Circuit Voltage | 450Vdc | ||
| PV Array MPPT Voltage Range | 55-450Vdc | ||
| Minimum battery voltage for PV charging | 2W | ||
| Power consumption in standby mode | +/-0.3% | ||
| Battery voltage accuracy | +/-2V | ||
| PV Voltage Accuracy | 3-Step | ||
| Charging Algorithm | |||
7.4. General Specifications
| INVERTER MODEL | 3.8KW 24V | 3.8KW 48V | 6.2KW 48V |
|---|---|---|---|
| Safety certification | CE | ||
| Operating temperature range | 0°C to 55°C | ||
| Storage temperature | -15°C to 60°C | ||
| Dimensions (T*B*H), mm | 423*290*100 (mm) | 423*290*105 (mm) | |
| Net weight, kg | 6.8KG | 6.9KG | 7.5KG |
8. User Tips
8.1. WiFi Module Connectivity
Several users have inquired about the compatible WiFi module for this inverter. The DATOUBOSS DT-24V3000W inverter supports an optional WiFi module for convenient real-time monitoring of its function status and parameters. This module allows for remote monitoring without distance limitations.
For specific recommendations on compatible WiFi modules and connection instructions, please refer to the full PDF user manual or contact DATOUBOSS customer support.
9. Warranty and Support
For detailed information regarding warranty coverage, technical support, and service, please refer to the official DATOUBOSS DT-24V3000W User Manual (PDF) provided with your product. You can also visit the DATOUBOSS website or contact their customer service for assistance.
