Victron Energy Skylla-TG 24/100 (1+1) Battery Charger

Overview

The Victron Energy Skylla-TG 24/100 is a mounted 24V battery charger for vessel service banks, with a 100A main charging output and a separate 4A output for topping up a starter battery. It uses a three-step IUoUo charge profile, with 28.5V absorption and 26.5V float charging values, and it suits 24V battery banks in the 500 to 1000Ah range.

This charger is a practical fit for larger boats with a 24V DC system, including cruising yachts, workboats, and fishing vessels that need a fixed charger for dockside charging or onboard power systems. Battery voltage sensing helps compensate for cable voltage loss, and the included temperature-sensing function adjusts charging behavior as battery temperature changes.

The enclosure is IP21 rated and built from blue aluminium, so it should be mounted in a dry, protected equipment space rather than in an exposed cockpit, lazarette, or washdown area. Plan for airflow around the unit, access to the M8 battery studs, and a location that keeps AC wiring and battery cabling serviceable.

Key features

• 24V charger with 100A charging current for the house battery bank and a separate 4A output for starter battery maintenance.
• Three-step IUoUo charging profile supports controlled charging for sealed and unsealed battery systems when set up correctly.
• Battery voltage sense connection helps the batteries receive the intended charge voltage when cable runs create voltage drop.
• Temperature sensor support reduces charge voltage as battery temperature rises, which is useful for sealed batteries in warm machinery spaces.
• Can be used as a stabilized DC power supply when batteries or large buffer capacitors are not available.
• Built-in protection covers output short circuit, battery reverse polarity detection, excessive battery voltage, and excessive temperature.
• IP21 aluminium enclosure with M8 battery studs and screw-clamp AC connection for fixed installation in a protected onboard electrical space.
• Operates across a -40 to +50°C temperature range, with full output current up to 40°C.

Variants

The Skylla-TG 24/100 is offered here in two configurations. Both versions share the 24V, 100A main charging output, the 4A starter battery output, the 500 to 1000Ah battery bank range, IP21 enclosure rating, M8 battery connections, and 365 x 250 x 257 mm housing size.

The main difference is the input and approval configuration. One version is for 230V AC installations, while the GL version adds the wider 120/230V input class and Germanischer Lloyd approval for protected marine installations.

• SDTG2401001: Input and approval: 230V. This version fits vessels wired around 230V AC supply and has a 185 to 264V AC input range, with 180 to 400V DC input accepted where the installation calls for DC supply.
• SDTG2401003: Input and approval: GL 120-240V. This version covers 120/230V AC input installations with a 90 to 265V AC range and 90 to 400V DC input, and it carries GL approval for protected shipboard equipment locations.

Installation and setup

Install the charger close enough to the battery bank to keep DC cable runs sensible, while leaving room for ventilation and service access. The battery connections use M8 studs, and the AC side uses a screw-clamp connection, so the surrounding installation should allow proper strain relief, overcurrent protection, and cable routing in line with the vessel electrical plan.

Because the charger is IP21 rated, it belongs in a dry interior location such as an electrical locker, technical compartment, or protected machinery space. It should not be treated as a deck-mounted or splash-exposed charger.

Electrical and system integration

The 4A auxiliary output is intended for maintaining a starter battery while the main output charges the house bank. This layout works well on boats where the 24V service bank handles larger DC loads and a separate starter battery needs maintenance charging without adding a second charger.

A Skylla Control panel can be paired with the charger when the installation needs remote charge-current adjustment, which is useful on shore power supplies with limited capacity. The charger also includes remote alarm contacts rated at 60V and 1A for integration with onboard monitoring or alarm wiring.

Use on board

This charger is a good match for 24V vessels with larger battery banks, steady hotel loads, or long dockside charging periods. It is especially relevant for boats where voltage drop, battery temperature, and starter battery maintenance need to be handled as part of one fixed charging installation.