The Victron BlueSolar PWM DUO-LCD&USB 12/24V-20A (SCC010020060) is a dual-output PWM solar charge controller for 12V and 24V battery systems. It delivers up to 20A of charge current and includes a built-in LCD display with a USB output port, making it suited to small off-grid installations, caravans, boats and remote power setups.

Key features

• Dual battery output (DUO), charges two separate battery banks from a single solar input.
• System voltage, 12V and 24V, with automatic voltage detection.
• Charge current, up to 20A.
• Display, built-in LCD showing battery voltage, charge current and charge state.
• USB output, 5V port for charging phones, tablets or other USB devices.
• Charge algorithm, PWM (Pulse Width Modulation).
• Weight, 0.377kg.

How it works

PWM charge controllers regulate the current flowing from the solar panel to the battery by switching the connection on and off at high frequency. As the battery approaches full charge, the controller reduces the average current delivered, avoiding overcharge without the tracking circuitry an MPPT controller uses. This keeps cost down on smaller systems where panel voltage is closely matched to the battery voltage.

The DUO output adds a second battery connection, useful on boats or campervans where a starter battery and a leisure battery need separate charging. The primary bank charges first; once it reaches its threshold the controller diverts charge to the secondary bank, so the secondary bank cannot draw down the primary.

Applications

• Campervans and motorhomes with separate starter and leisure batteries.
• Boats and narrowboats with dual battery bank setups.
• Small off-grid cabins, sheds or outbuildings on 12V or 24V systems.
• Remote monitoring stations or security installations with low power needs.
• Portable solar setups needing USB device charging alongside battery charging.

Installation notes

This controller is for 12V and 24V off-grid battery systems only, not for grid-connected installations. Check that the solar panel's open-circuit voltage does not exceed the controller's rated input, and follow Victron's wiring guidance for correct sequencing between primary and secondary banks. Fit fuses on both battery and solar connections close to the source, and have the installation carried out by someone familiar with low-voltage DC systems.

What's in the box

• 1x Victron BlueSolar PWM DUO-LCD&USB 12/24V-20A charge controller