1. Kupu Whakataki
Thank you for choosing the Offgridtec MPPT Pro Duo charge controller. This device is designed to efficiently manage solar power input to charge two independent battery banks, typically a main service battery and a starter battery, in 12V or 24V systems. It utilizes Maximum Power Point Tracking (MPPT) technology to optimize energy harvest from your solar panels. Please read this manual thoroughly before installation and operation to ensure safe and optimal performance.

Whakaahua 1: Mua view of the Offgridtec MPPT Pro Duo Charge Controller.
2. Nga Tohutohu Haumaru
Always observe the following safety precautions to prevent personal injury or damage to the controller and connected equipment:
- Ko te whakaurunga me mahi e nga kaimahi mohio anake.
- Ensure all power sources (solar panels, batteries) are disconnected before installation or maintenance.
- Whakamahia ngā taputapu e tika ana, ā, mau hoki i ngā taputapu tiaki.
- Do not disassemble or attempt to repair the controller. Contact Offgridtec support for assistance.
- Me whakarite kia tika te hau huri noa i te kaiwhakahaere kia kore ai e wera rawa.
- Connect batteries with correct polarity. Reverse polarity can cause severe damage.
- Use fuses or circuit breakers on all battery and solar panel connections as recommended by local regulations and system design.
- Avoid short-circuiting battery terminals or solar panel wires.
- Keep the controller away from flammable materials, moisture, and direct sunlight.
3. Hua Neke Atuview
3.1 Nga waahanga matua
- Dual battery charging: Charges both main (service) and starter batteries.
- MPPT Technology: Maximizes power harvest from solar panels.
- Supports 12V and 24V systems.
- Maximum charge current up to 30A.
- Adaptive three-level charging for extended battery life.
- Supports various battery types: Gel, Flooded, LiFePO4, Li-NiCoMn (for main battery).
- Secondary charge output for starter battery (supports lead-acid).
- Optional remote display and Bluetooth compatibility (accessories required).
- AES control signal for car refrigerators to prevent energy waste.
- Standard bus protocol and RS485 communication connection.
- Robust aluminum heatsink design for efficient cooling.
- Overload, reverse polarity, and deep discharge protection.
3.2 Waehanga
The Offgridtec MPPT Pro Duo charge controller includes:
- MPPT Pro Duo Charge Controller unit.
- Nga pito hononga.
- Integrated LED status indicators.
- SET button for battery type selection.
- Temperature sensor ports (one with integrated sensor, one for external).
- Tauranga korero RS485.
- AES signal output port.

Whakaahua 2: Mua me muri view of the charge controller, highlighting the heatsink design.
4. Tatūnga me te Tāuta
Proper installation is crucial for the safe and efficient operation of your charge controller. Ensure all safety instructions are followed.
4.1 Te Tauwhi Maunga
- Mount the controller vertically on a non-flammable surface.
- Ensure adequate air circulation around the heatsink for optimal cooling.
- Avoid locations exposed to direct sunlight, high temperatures, or moisture.
- Dimensions: 24.7 cm (L) x 16.5 cm (W) x 6.9 cm (H).
- Mounting holes diameter: 5 mm.

Figure 3: Physical dimensions of the MPPT Pro Duo charge controller, showing the aluminum heatsink.
4.2 Kauwhata Waea me ngā Hononga
Follow the wiring sequence below. Incorrect wiring can damage the controller or batteries.
- Connect Battery 1 (Main/Service Battery): Connect the positive and negative terminals of your main battery to the BATT1 terminals on the controller. Use appropriate cable gauge (e.g., 16 mm² / AWG6). Ensure correct polarity.
- Connect Battery 2 (Starter Battery): Connect the positive and negative terminals of your starter battery to the BATT2 terminals on the controller. Use appropriate cable gauge (e.g., 4 mm² / AWG12). Ensure correct polarity.
- Connect Solar Panels (PV): Connect the positive and negative terminals of your solar panel array to the PV terminals on the controller. Ensure the open-circuit voltage of your solar array does not exceed 100V.
- Connect Temperature Sensors: The controller includes ports for temperature sensors. Connect the provided sensor to monitor battery temperature for optimized charging.
- Hononga Kōwhiringa:
- RS485 Whakawhitiwhiti: For connecting an optional remote display or USB adapter for PC communication.
- AES Signal Output: For controlling car refrigerators to prevent excessive discharge of the main battery.
- Whakapapa: Ensure the controller is properly grounded (negative grounding).

Figure 4: Simplified wiring diagram showing connections from solar panel to controller and dual batteries.

Whakaahua 5: Example installation of the charge controller in a recreational vehicle.
5. Nga Tohutohu Whakahaere
5.1 Whakanui-a-Tamatanga
After all connections are securely made, connect the battery power first, then the solar panel power. The controller will perform a self-test, and the LED indicators will illuminate.
5.2 Setting Battery Type (BATT1)
The controller supports various battery types for the main battery (BATT1). To select the correct battery type:
- Patohia me te pupuri i te SET button for approximately 5 seconds until the battery type indicator starts flashing.
- Pehia te SET button repeatedly to cycle through the available battery types (Gel, Flooded, LiFePO4, Li-NiCoMn).
- Once the desired battery type is selected, wait for 5 seconds without pressing any button. The indicator will stop flashing, and the setting will be saved.
The secondary battery (BATT2) is typically charged as a lead-acid battery and does not require specific type selection.
5.3 Tohu LED
The front panel features LED indicators to show the operational status:
- PV Status LED: Indicates solar panel input status.
- BATT1 Status LEDs: Show the charging stage and state of charge for the main battery.
- BATT2 Status LED: Indicates charging status for the starter battery.
- Hapa LED: Illuminates to indicate a fault or warning. Refer to the troubleshooting section.

Figure 6: Installed charge controller showing illuminated LED indicators.
5.4 Tukatuka Toha
The MPPT Pro Duo uses an adaptive three-level charging algorithm to optimize battery health and lifespan. It prioritizes charging the main battery (BATT1) and then provides a maintenance charge to the starter battery (BATT2).
- Akona Ake: Delivers maximum current to rapidly charge the battery.
- Utu horomanga: Maintains a constant voltage to fully charge the battery without overcharging.
- Ake Whakatika: Reduces voltage to a lower level to maintain the battery at full charge and compensate for self-discharge.
6. Tiaki
Mā te tiaki auau ka roa te ora me te mahi tino pai o tō kaiwhakahaere utu:
- Tirotiro Ataata: Periodically check for loose connections, damaged wiring, or signs of corrosion.
- Te horoi: Keep the controller clean and free of dust. Use a dry cloth to wipe the exterior. Do not use liquids or solvents.
- Whakahau: Ensure the heatsink fins are not obstructed to allow for proper heat dissipation.
- Taki Hononga: Verify that all terminal connections are tight and secure.
- Hauora Pūhiko: Monitor the health of your batteries. A failing battery can affect the performance of the entire system.
7. Te Raru
If you encounter issues with your MPPT Pro Duo, refer to the following common problems and solutions:
| Raruraru | Take pea | Rongoā |
|---|---|---|
| No LED indicators lit. | No power from battery or solar panels; reverse polarity. | Check battery and solar panel connections and polarity. Ensure fuses are intact. |
| Kaore nga pākahiko e utu ana. | Low solar input; incorrect battery type setting; loose connections; faulty solar panel or battery. | Verify solar panel output. Check battery type setting. Inspect all wiring. Test solar panels and batteries independently. |
| Error LED is lit. | Te taumaha, ara iahiko poto, over-voltage, over-temperature, or other system fault. | Disconnect all power, inspect wiring for shorts or damage. Allow controller to cool if overheating. Reconnect power in correct sequence. If error persists, contact support. |
| Bluetooth connection issues (with optional adapter). | Incorrect password; app not installed correctly; location services disabled for app. | Try alternative passwords (refer to adapter manual). Reinstall the app. Enable location services for the app on your mobile device. |
| Secondary battery (BATT2) not charging or charging slowly. | Main battery (BATT1) not fully charged; low solar input; faulty BATT2 connection. | Ensure BATT1 is adequately charged. Verify solar input. Check BATT2 wiring and health. Note that BATT2 receives a compensatory charge after BATT1. |
If the problem persists after attempting these solutions, please contact Offgridtec customer support.
8. Whakatakotoranga
| Tawhā | Uara |
|---|---|
| Tauira | MPPT Pro Duo 12V/24V 30A |
| Pūnaha Voltage | 12V / 24V (Pūrongo-aunoa) |
| Max. Utu o naianei | 30A |
| Mana Whakauru PV Mōrahi (Pūnaha 12V) | 390W |
| Mana Whakauru PV Mōrahi (Pūnaha 24V) | 780W |
| Max. PV Open Circuit Voltage | 100V |
| Whakapapa whenua | He kino |
| Supported Battery Types (BATT1) | Gel, Flooded, LiFePO4, Li-NiCoMn |
| Supported Battery Types (BATT2) | Hua-waikawa |
| Te kaha | Tae atu ki te 98% |
| Ahu (L x W x H) | 24.7 cm x 16.5 cm x 6.9 cm |
| Taumaha | 1.4 kg |
| Te Waahi Mahi | Tae atu ki te 60 Degree Celsius |
| Whakamahi Hiko | 26 mA (12V), 15 mA (24V) |
| Kaihanga | Offgridtec GmbH |
| Tohutoro Hua / Tauira Tau | 011200 |
9. Pūtāhui me te Tautoko
For warranty information, please refer to the terms and conditions provided at the time of purchase or contact Offgridtec GmbH directly. Keep your proof of purchase for any warranty claims.
For technical support, troubleshooting assistance beyond this manual, or inquiries about accessories, please contact Offgridtec customer service. Contact details can typically be found on the manufacturer's official webpae, to tuhinga hoko ranei.
10. Nga Tono Tikanga
The Offgridtec MPPT Pro Duo charge controller is suitable for a variety of off-grid and mobile solar power systems, including:
- Recreational Vehicles (RVs) and Campervans
- Marine Systems (Boats & Yachts)
- Remote Telecommunication Stations
- Off-grid Cabins and Small Homes
- Camping and Outdoor Solar Setups

Whakaahua 7: Examples of typical applications for the MPPT Pro Duo charge controller.





