Solar charge controller QOLTEC MPPT 20A 12V/24V with 2×USB ports

QOLTEC MPPT 20A 12V/24V solar charge controller provides maximum power point tracking to optimize energy harvest from photovoltaic panels for 12V or 24V battery systems. The controller supports up to 20A charging current and includes two USB ports for direct charging of phones and small devices. It performs regulated charging, battery protection and basic system monitoring functions suitable for off-grid installations, recreational vehicles, boats and small backup power systems.

Advantages

The MPPT algorithm increases charging efficiency by continuously adjusting panel operating point to extract maximum available power. Built-in battery regulation protects against overcharge, deep discharge and reverse polarity, while the two USB ports allow convenient on-site charging of mobile devices without additional adapters. Compact housing and clear connection terminals simplify installation in limited-space applications.

Suitable for

• Small off-grid solar systems for cabins and remote power
• RVs, campervans and caravans requiring battery maintenance
• Marine applications such as boats and yachts with 12V/24V battery banks
• Backup power systems for lighting and low-power electronics

Key specifications

• Nominal system voltages: 12V and 24V automatic detection
• Maximum charging current: 20A
• MPPT algorithm for improved solar panel efficiency
• Two USB output ports for charging small devices
• Battery charge regulation with multi-stage charging profiles
• Protection features: overcharge protection, deep discharge prevention, reverse polarity protection
• Connection type: screw terminals for PV, battery and load
• Compact form factor suitable for small installations

How to use

Mount the controller in a dry, ventilated location close to the battery bank and within reach of PV cable runs. Ensure correct system voltage selection (the device supports automatic detection of 12V/24V). Connect the battery first, then the solar panel input, and finally any load; follow correct polarity to avoid damage. Use the USB ports to charge phones or small electronics directly. Observe wiring guidelines and recommended wire gauges for the 20A current rating.

Usage recommendations

For optimal performance, pair the controller with panels whose combined open-circuit voltage remains within the device's allowable PV input range and size the array to match the 20A maximum charge current. Regularly check battery electrolyte levels if using flooded batteries and inspect connections for corrosion. Avoid installing the controller in direct sunlight or near heat sources to maintain thermal stability and prolong service life.