Radio Parts MB3613
MB3613 SLA Battery Charger User Manual
Model: MB3613 | Brand: Radio Parts
Product Overview
The Radio Parts MB3613 is a fully automatic 9-stage battery charger designed for both 12V and 24V lead-acid batteries (Wet cell, Gel cell, AGM) and Lithium Iron Phosphate (LiFePO4) batteries. This advanced unit incorporates diagnostics to optimize charging rates and extend battery life. It delivers up to 7.2A for 12V batteries and 3.6A for 24V batteries. Key features include multi-stage charging, desulphation, and recondition modes, making it a versatile solution for various applications such as cars, 4WDs, trucks, and boats.

Figure 1: MB3613 Battery Charger with included battery clamps and ring terminal connectors.
Safety Information
Always read and understand all safety warnings and instructions before operating the charger. Failure to follow these instructions may result in electric shock, fire, or serious injury.
- Ensure adequate ventilation during charging to prevent overheating.
- Do not expose the charger to rain or wet conditions.
- Always disconnect the AC power before connecting or disconnecting battery leads.
- Avoid charging frozen batteries.
- Keep out of reach of children.
Setup and Connection
Before connecting the charger, ensure the battery terminals are clean and free of corrosion. The charger comes with two types of battery connectors: battery clamps and ring terminals.

Figure 2: Included battery clamps and ring terminal connectors.
- Select Connector: Choose either the battery clamps for temporary connection or the ring terminals for a more permanent installation.
- Connect to Battery:
- Connect the red (+) charger lead to the positive (+) battery terminal.
- Connect the black (-) charger lead to the negative (-) battery terminal.
- Ensure connections are secure.
- Connect to Mains Power: Plug the charger's AC power cord into a suitable 220V AC power outlet.

Figure 3: MB3613 Battery Charger with its mains power plug.
Operating Instructions
The MB3613 charger features a clear LCD display and a "Mode" button for operation.

Figure 4: Charger display and "Mode" button.
- Power On: Once connected to the battery and mains power, the charger will power on and display the current battery voltage.
- Select Charging Mode: Press the Mode button to cycle through the available charging programs. The charger automatically detects 12V or 24V, but you can select specific modes for different battery types (e.g., AGM, LiFePO4) or functions (e.g., Recondition, Power Supply).
- Charging Process: The charger will automatically begin the 9-stage charging process. The display will show charging status, voltage, and current. Indicators for "Float" and "Low" may also be present.
- Desulphation/Recondition: If selected, these modes will attempt to restore deeply discharged or sulphated batteries.
- Power Supply Mode: This mode provides a stable 13.8V DC output up to 5.0A, useful for powering 12V devices or maintaining vehicle electronics during battery changes.
- Charging Completion: The charger will automatically switch to maintenance (float) mode once the battery is fully charged.
- Disconnecting: Always disconnect the mains power first, then disconnect the battery leads (negative first, then positive).
Maintenance
Proper maintenance ensures the longevity and safe operation of your MB3613 charger.
- Cleaning: Wipe the charger casing with a soft, dry cloth. Do not use abrasive cleaners or solvents.
- Storage: Store the charger in a cool, dry place when not in use. Ensure cables are neatly coiled to prevent damage.
- Cable Inspection: Periodically inspect the AC power cord and battery leads for any signs of damage, fraying, or exposed wires. Do not use the charger if any cables are damaged.
Troubleshooting
If you encounter issues with your MB3613 charger, refer to the following common problems and solutions:
| Problem | Possible Cause | Solution |
|---|---|---|
| Charger does not power on. | No AC power; loose connections. | Check mains power outlet; ensure AC cord and battery leads are securely connected. |
| Charger shows error or does not charge. | Reverse polarity; battery too low; faulty battery. | Check battery connections for correct polarity (+ to +, - to -); battery voltage may be too low for charger to detect (try a different charger or jump start); battery may be beyond recovery. |
| Charger overheats. | Poor ventilation; prolonged high load. | Ensure charger is in a well-ventilated area; reduce load if possible (though charger is designed for continuous use). If overheating persists, discontinue use and contact support. |
Specifications
| Feature | Detail |
|---|---|
| Model | MB3613 |
| Brand | Radio Parts |
| Compatible Battery Types | Lead Acid (Wet cell, Gel cell, AGM), Lithium Iron Phosphate (LiFePO4) |
| Output Voltage (Nominal) | 12V, 24V |
| Output Current (12V) | Up to 7.2A |
| Output Current (24V) | Up to 3.6A |
| Charger Output Voltage (Specific) | 5.0V, 10.0V, 14.7V, 29.4V |
| Charging Stages | 9-Stage Automatic |
| Protection Features | Reverse Polarity Protection |
| Additional Functions | Power Supply Mode (13.8V @ 5.0A), Desulphation, Recondition |
| Mains Voltage Range | 220V AC |
| Mains Max Current | 1.3A |
| Mains Connection | AU/NZ 2 Pin (No Earth) |
| Package Dimensions | 31.6 x 20.2 x 7.4 cm |
| Item Weight | 5 kg |
Warranty and Support
This MB3613 SLA Battery Charger comes with a 1 Year Warranty from the date of purchase.
For technical support or warranty claims, please contact your retailer or the manufacturer, Radio Parts, directly. Please have your proof of purchase and product model number (MB3613) ready when contacting support.
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