1. Introduction
The ZK-SJ30 is a high-power 700W synchronous rectification automatic boost-buck power supply module, designed for various applications including solar charging, battery charging, and LED constant current drive. This versatile module features Maximum Power Point Tracking (MPPT) for efficient solar energy utilization, adjustable DC stabilized power output, and comprehensive protection mechanisms. It can function as a buck (step-down) or boost (step-up) regulator, automatically adjusting to maintain the desired output voltage and current.
This manual provides detailed instructions for the safe and effective use of your ZK-SJ30 module, covering installation, operation, specifications, and troubleshooting.
2. Product Features
- High Power Output: Up to 700W dissipation power.
- Wide Input Voltage Range: DC 6-80V.
- Adjustable Output Voltage: DC 1.3-78V.
- Automatic Boost-Buck Function: Automatically adjusts voltage up or down to maintain stable output.
- MPPT (Maximum Power Point Tracking): Optimizes power extraction from solar panels.
- Constant Current (CC) Regulation: Ideal for battery charging and LED constant current drive.
- Visual Adjustment: Potentiometers for MPPT voltage, output voltage, and output current limiting.
- Enhanced Heat Dissipation: Features large heat dissipation fins and MOS tubes. Includes a reserved 12V fan port for optional external fan connection (fan not included by default).
- LCD Display: Real-time display of input voltage, output current, output voltage, output power, and MPPT voltage.
- User-Friendly Controls: Output switch button and display switch button for easy operation.
- Anti-Backflow Protection: Built-in anti-reverse function, eliminating the need for an external diode when charging batteries.
- Overpower Protection (OPP): Automatically turns off output if power exceeds 700W.
3. Specifications
Figure 3.1: ZK-SJ30 Product Parameters
| Parameter | Value |
|---|---|
| Input Voltage Range | DC 6-80V |
| Output Voltage Range | DC 1.3-78V |
| Voltage Display Range | 1.40-80.00V (Accuracy ±0.1V) |
| Output Current Regulation Range | 0-30A |
| Current Display Range | 0.00A-30.00A (Accuracy ±0.03A) |
| Adjusting Knobs | MPPT voltage regulation, output voltage regulation, output current limiting regulation |
| MPPT Function | Yes |
| Anti-Backflow | Yes (no need for external diode to battery) |
| Constant Current (Current Limiting) | Yes |
| Overpower Protection | 700W (output turned off and OPP displayed if exceeded) |
| Size | 110mm x 93.5mm x 46mm |
| Product Weight (with display) | 223g |
| Product Weight (without display) | 209g |
| Package Weight (with display) | 259g |
| Package Weight (without display) | 244g |
| Application | Solar charging, lithium battery charging, LED constant current drive, regulated power supply |
| Customization | Yes |
| Condition | New |
Figure 3.2: ZK-SJ30 Product Dimensions and Installation Hole Size
4. Safety Information and Precautions
Figure 4.1: Important Safety Notes and Reminders
- Polarity: The input positive and negative poles must not be connected reversely, as this will damage the module.
- Battery Connection: When connecting the output terminal to a battery, ensure the positive and negative electrodes are not reversed to prevent damage.
- Current and Power Limits: The maximum output current of 30A is only achievable when the difference between input and output voltage is small, and the output power does not exceed 700W. A greater voltage difference can lead to lower conversion efficiency and increased heating. If excessive heating occurs, reduce the power usage or install an optional 12V fan (with a fan current less than 200mA) to assist in heat dissipation.
- MPPT Voltage Setting: The MPPT voltage is typically set to 0.75 times the open circuit voltage of the solar panel. Refer to the solar panel manufacturer's nameplate or Vmp parameter value for precise settings. The display screen can show the set voltage for easy adjustment.
- Output Current Limiting (CC): The CC value is generally the allowable charging current of the rechargeable battery. To set this, short-circuit the output terminals with a suitable wire and adjust the CC potentiometer while observing the current display value. The displayed value represents the current limiting value (maximum output current).
- Anti-Reverse Function: The product includes an anti-reverse function, meaning the output end of the charging pool does not require an additional anti-reverse diode.
5. Setup Instructions
Figure 5.1: ZK-SJ30 Wiring Diagram and Control Layout
- Identify Terminals: Locate the input (IN+ and IN-) and output (OUT+ and OUT-) terminals on the module. Ensure correct polarity.
- Connect Input Power: Connect your DC power source (e.g., solar panel, DC power supply) to the IN+ (positive) and IN- (negative) terminals. Ensure the input voltage is within the DC 6-80V range.
- Connect Output Load: Connect your load (e.g., battery, LED array) to the OUT+ (positive) and OUT- (negative) terminals. Ensure correct polarity, especially when connecting to batteries.
- Optional Fan Connection: If using an external 12V fan for enhanced cooling, connect it to the designated 12V fan port. Ensure the fan current is less than 200mA.
5.1. Solar Cell Charging Setup Steps
Figure 5.2: Solar Cell Charging Steps
- Determine MPPT Voltage: Measure the no-load voltage of your solar panel under sufficient sunlight. Calculate the MPPT voltage as approximately 0.75 times the no-load voltage, or directly use the Vmp parameter value provided by the solar panel manufacturer.
- Initial Module Power-Up: Access the solar panel to supply power to the module. Switch the display to the MPPT voltage display interface.
- Adjust MPPT Potentiometer: Adjust the MPPT potentiometer (CVT) to set the value to the determined Vmp voltage.
- Adjust Output Voltage (CV): Rotate the CV potentiometer to adjust the output voltage. For battery charging, this is typically the floating charge voltage of the battery bank.
- Adjust Output Current Limit (CC): Short circuit the positive and negative terminals of the output with a suitable wire. Adjust the CC potentiometer to set the desired current limit, which should be the allowable charging current of the rechargeable battery. If the solar panel's power is too low, the MPPT indicator light will illuminate, and the output current will be limited. It is recommended to use sufficient sunlight or adjust the current when using a constant voltage source as input.
- Connect Battery: Connect the battery to be charged to the output terminals. Ensure correct polarity (positive to OUT+, negative to OUT-). The MPPT potentiometer can be fine-tuned to ensure the module operates at the maximum power point output for optimal charging.
6. Operating Instructions
Figure 6.1: Introduction to Buttons
6.1. Output Switch Button (ON/OFF)
- Click: Toggles the output ON or OFF.
- Long Press (2 seconds): Sets the default power-on state. If the display shows "ON", the output will be enabled automatically upon power-up. If the display shows "OFF", the output will remain off until manually activated.
6.2. Display Switch Button (IN/OUT)
- Click: Cycles through the uplink display modes: Input Voltage, Output Voltage, and MPPT Voltage.
- Long Press: Switches to the downstream display mode, showing Current and Power.
- Press and Hold (10 seconds): Initiates a current reset. Hold until "0.00A" is displayed, indicating a successful reset.
6.3. Interface Display
Figure 6.2: Interface Display Modes
The LCD display provides real-time monitoring of various parameters:
- Input Voltage / Output Current: Displays the voltage at the input and the current flowing out.
- Output Voltage / Output Power: Shows the voltage at the output and the power being delivered.
- Input Voltage / Output Power: Displays the input voltage and the output power.
- MPPT Voltage / Output Power: Shows the tracking point voltage (MPPT voltage or Vmp voltage) and the output power. This interface is crucial for solar charging applications.
The MPPT indicator light illuminates when the input voltage is lower than the set MPPT voltage, indicating that the module is actively limiting output to maintain input voltage, ensuring the solar panel charges the battery at its maximum power point.
7. Maintenance
- Heat Dissipation: Regularly inspect the heat dissipation fins for dust or obstructions. Keep the area around the module clear to ensure adequate airflow.
- Optional Fan: If an external 12V fan is installed, ensure it is functioning correctly and free from debris. Clean fan blades periodically if necessary.
- Connections: Periodically check all wiring connections for tightness and signs of corrosion. Loose connections can lead to poor performance or overheating.
- Storage: When not in use for extended periods, store the module in a dry, cool environment, away from direct sunlight and extreme temperatures.
8. Troubleshooting
| Problem | Possible Cause | Solution |
|---|---|---|
| Module not powering on / No display | Incorrect input voltage or polarity; loose connections. | Verify input voltage is within DC 6-80V. Check input polarity (IN+ to positive, IN- to negative). Ensure all connections are secure. |
| No output voltage/current | Output is switched off; incorrect output settings; overpower protection (OPP) activated. | Click the ON/OFF button to enable output. Check output voltage (CV) and current limit (CC) settings. If "OPP" is displayed, reduce load or input power to stay within 700W. |
| Module overheating | Exceeding 700W power; insufficient ventilation; high ambient temperature. | Reduce load to stay within 700W. Ensure adequate airflow around the module. Consider installing an external 12V fan to the fan port. |
| MPPT indicator light is ON constantly | Input voltage is lower than the set MPPT voltage, or solar panel power is too small. | This indicates the module is actively limiting output to maintain input voltage. Ensure sufficient sunlight for solar panels or adjust current if using a constant voltage input. |
| Current display is inaccurate or stuck | Internal error or calibration issue. | Press and hold the IN/OUT button for 10 seconds to perform a current reset. |
9. User Tips
- Solar Charging: This module is specifically designed to function as an MPPT charge controller for solar battery charging. Ensure proper MPPT voltage setting for optimal efficiency.
- Heat Management: For continuous high-power operation, especially near the 700W limit, consider adding an external 12V cooling fan to the dedicated fan port to prevent overheating and ensure longevity.
- Potentiometer Adjustment: The module uses screwdriver-free potentiometers for direct manual adjustment, making fine-tuning easier.
10. Warranty and Support
For warranty information, technical support, or service inquiries, please contact your retailer or the manufacturer. Keep your purchase receipt as proof of purchase.
