Optimized Converter Performance for RVs

Many recreational vehicles (RVs) come equipped with at least one 12VDC accessory battery, typically a lead acid, gel cell, or lithium deep-cycle battery. These batteries are designed to handle slow power drains, enabling the RV owner to use essential 12VDC appliances when away from shore power. Examples of these devices include lights, water pumps, and refrigerators.

When an RV is plugged into AC power, the converter/charger system kicks in, charging the battery as needed while simultaneously providing clean power to 12VDC systems. PowerMax converter/chargers are engineered to keep the battery charged and ready for use when disconnecting from AC power or switching off the generator.

PowerMax 3-Stage Smart Charging Technology

PowerMax converters feature a 3-Stage Smart Charging process, which automatically cycles through three modes—Absorption, Bulk, and Float—along with a Fixed Mode option for flexibility and efficiency in charging.

Bulk Mode

The Bulk Mode is activated when the battery is significantly discharged. This mode is optimized for faster charging than Absorption Mode. The converter detects a low battery voltage and increases the output voltage to 14.4V DC to charge the battery quickly. While this higher voltage speeds up charging, it continues to deliver clean 12VDC power to the RV’s systems.

During Bulk Mode, the converter may not consistently provide a 14.4V DC output, so it’s important to reduce some DC loads to achieve the correct voltage reading on a meter. As the battery charges, the current drawn from the converter decreases, and once the battery reaches a sufficient charge, the PowerMax converter will automatically switch to the next mode. For battery protection, the Bulk Mode duration is limited to a maximum of four hours.

Absorption Mode

Absorption Mode serves as the default charging mode with a 13.6V DC output. This mode begins once the battery is connected, allowing the converter to supply power as needed. The charging current varies depending on the battery’s charge level—fully charged batteries draw minimal current, while discharged batteries draw more.

The time it takes to fully charge the battery in Absorption Mode is influenced by the DC load in use. For example, a 20-amp load will charge the battery in roughly three hours, but additional DC devices will lengthen the charging time. Voltage and amperage are interconnected—if the DC load increases beyond the converter’s maximum rated current, the voltage output will drop, prompting the converter to shift to Bulk Mode for a higher charging voltage.

Float Mode

Float Mode maintains the battery’s charge over extended periods when the RV is not in use. If the converter detects no significant changes in current draw for approximately 44 continuous hours, it will reduce the voltage from 13.6V to 13.2V. This helps preserve the battery’s life while keeping it ready for use. If the converter senses a change in current draw, it will revert to Absorption Mode to continue charging the battery.

Fixed Output Mode

The Fixed Output Mode offers more control over the voltage level. By selecting this mode via a switch, the converter provides a constant, preset output voltage for powering 12V equipment or maintaining the battery at the set voltage.

To activate Fixed Mode, turn off the unit, move the selector switch to "Fixed Voltage," then plug the converter into a 110V power source. Use the voltage adjustment switch to fine-tune the output between 13V and 16.5V to meet your needs. The output voltage will remain constant at the selected level each time the unit is powered on.

To reset the converter to its default 3-Stage Smart Charging settings, turn off the unit, set the selector switch to "Three Stage," and power the unit back on. Adjust the voltage to 14.6V using the voltage switch, restoring the factory settings.

By leveraging PowerMax’s advanced 3-Stage Smart Charging technology, RV owners can ensure their batteries remain fully charged and ready for use, whether the RV is connected to AC power or operating off-grid. The ability to seamlessly switch between Bulk, Absorption, Float, and Fixed Output Modes allows for maximum charging efficiency, longer battery life, and a hassle-free RV experience.