1. Product Overview
The NOCO Genius GENM2 is a fully-automatic, smart marine battery charger designed for charging and maintaining two independent 12-volt batteries. It delivers 8 amps total output, with 4 amps per bank, making it suitable for a variety of lead-acid battery types.
Figure 1: NOCO Genius GENM2 On-Board Battery Charger. This image shows the compact, rugged design of the charger with its two output cables and AC input.
This charger features a fully-sealed, waterproof housing, rated IP68 and NEMA 6P, allowing for installation in tough marine environments and submersion up to 3 meters without failure. Its advanced charging technology includes an onboard processor capable of detecting, diagnosing, recovering, charging, and maintaining all types of lead-acid batteries, including Wet Cell (Flooded), Gel Cell, AGM, and Deep-Cycle batteries, without overcharging.
Key features include spark-proof technology, reverse polarity protection, thermal protection, ignition protection, and overcharge protection, ensuring safe and worry-free operation. The GENM2 continuously monitors the battery, identifying potential issues and automatically adjusting its charging cycle for optimal battery maintenance.
2. Package Contents
- GENM2 On-Board Battery Charger
3. Safety Information
Before using the NOCO Genius GENM2 charger, read all safety instructions. This device is designed with multiple safety features to protect both the user and the battery.
- Spark-Proof Technology: Prevents sparks during connection, enhancing safety.
- Reverse Polarity Protection: Protects against damage if battery connections are reversed.
- Thermal Protection: Monitors internal temperature to prevent overheating.
- Ignition Protection: Designed for safe use in environments where flammable vapors may be present.
- Overcharge Protection: Automatically stops charging when the battery is full, preventing damage.
The GENM2 is certified to UL1236, ISO 8846 Marine Standards, and Ignition Protection US Coast Guard 33 CFR 183.410, ensuring compliance with stringent safety regulations.
Always ensure proper ventilation when charging batteries. Do not attempt to charge frozen batteries. Disconnect the AC power before making or breaking battery connections.
4. Setup and Installation
The GENM2 charger is designed for easy installation directly onto various applications, particularly in marine environments. Its robust, waterproof construction allows for flexible mounting options.
Figure 2: NOCO Genius GENM2 with all cables connected. This image illustrates the AC input cable and the two independent output cables with battery terminals.
- Mounting: Choose a suitable, secure location for the charger. Ensure it is accessible for AC power connection but protected from physical damage. The waterproof design allows for mounting in damp or wet areas.
- Battery Connection: Connect the charger's output cables to your 12-volt batteries. Each bank (Bank 1 and Bank 2) operates independently. Ensure correct polarity: connect the red positive (+) terminal to the positive battery post and the black negative (-) terminal to the negative battery post.
- AC Power Connection: Once battery connections are secure, plug the charger's AC power cord into a compatible 120V AC outlet.
The charger will automatically begin its charging process once connected to AC power and batteries.
5. Operating Instructions
The NOCO Genius GENM2 is a fully-automatic charger. Once connected, it will assess the battery condition and initiate the appropriate charging mode.
Figure 3: Close-up of the NOCO Genius GENM2 LED indicators. This image highlights the 'CHARGE' and fault indicators for each bank, providing visual feedback on the charging status.
- Automatic Operation: The charger's onboard processor automatically detects the battery type and condition, then initiates a multi-stage charging process. This includes diagnosis, recovery (for deeply discharged batteries), bulk charging, absorption, and maintenance (float) modes.
- LED Indicators: The charger features LED indicators for each bank to display the charging status. A solid green 'CHARGE' LED typically indicates a fully charged battery in maintenance mode. Other indicator patterns may signal different charging stages or fault conditions (refer to troubleshooting for details).
- Continuous Monitoring: The GENM2 continuously monitors the connected batteries. It will automatically shut off power when a battery is fully charged and then transition to a maintenance mode to keep the battery at optimal charge without overcharging.
6. Maintenance
Regular maintenance ensures the longevity and optimal performance of your NOCO Genius GENM2 charger and connected batteries.
- Cleaning: Periodically clean the charger's exterior with a soft, damp cloth. Do not use harsh chemicals or abrasive cleaners.
- Cable Inspection: Regularly inspect all cables and connections for any signs of wear, damage, or corrosion. Replace damaged cables immediately.
- Connection Integrity: Ensure battery terminals are clean and connections are tight to prevent resistance and ensure efficient charging.
- Storage: When not in use for extended periods, store the charger in a cool, dry place.
7. Troubleshooting
If you encounter issues with your GENM2 charger, refer to the following common troubleshooting steps:
- Charger Not Turning On:
- Ensure the AC power cord is securely plugged into a live outlet.
- Verify that the battery connections are correct and secure (positive to positive, negative to negative).
- Check for any tripped circuit breakers in the AC supply.
- Battery Not Charging:
- Confirm that the battery voltage is within the charger's operating range (12V).
- Inspect battery terminals for corrosion and clean if necessary.
- The charger may enter a 'recovery' mode for deeply discharged batteries, which can take time. Observe the LED indicators.
- If a fault indicator (e.g., red LED) is illuminated, refer to the specific fault code in the full product manual for detailed resolution.
- Overheating:
- Ensure the charger has adequate ventilation and is not covered.
- If the charger feels excessively hot, disconnect it immediately and allow it to cool before re-evaluating.
For persistent issues or specific fault codes not covered here, consult the complete NOCO Genius GENM2 product manual or contact customer support.
8. Specifications
| Brand | NOCO |
| Model | GENM2 |
| Output Voltage | 12 Volts (14.4 Volts max) |
| Output Current | 8 Amps (4 Amps per bank) |
| Battery Compatibility | 20-120Ah, 12V Lead-Acid (Wet, Gel, AGM, Deep-Cycle) |
| Waterproof Rating | IP68, NEMA 6P (Submersible up to 3 meters) |
| Dimensions | 7.9 x 2.2 x 5.5 inches |
| Item Weight | 5.8 pounds |
| Certifications | UL1236, ISO 8846 Marine Standards, 33 CFR 183.410 |
9. Warranty and Support
The NOCO Genius GENM2 On-Board Battery Charger is backed by a 5-Year Limited Warranty. This warranty covers defects in material and workmanship under normal use and service.
For warranty claims, technical support, or further assistance, please refer to the official NOCO website or contact their customer service department. Keep your proof of purchase for warranty validation.
