Victron Skylla-TG 24/50 (1+1) GL 120-240V 50A Battery Charger

The Victron Skylla-TG 24/50(1+1) GL 120-240V (MPN: SDTG2400503) is a high-performance 24V battery charger with a 50 A charging current, a universal AC input, and an additional 4 A output for charging a starter battery. The microprocessor-controlled charging system operates using an IUoUo charging curve and takes into account both the battery temperature and potential voltage drops in the wiring. This allows the charging voltage to be precisely adjusted to the connected battery. The GL version of the unit is designed for marine and professional applications.

Precise 24 V battery charging with 50 A and a separate starter battery output

• 50 A charging current for the main battery
• Additional, galvanically isolated 4 A output for a starter battery
• Wide input voltage range of 90–265 V AC
• Adjustable charging voltages to accommodate different battery types
• Temperature compensation via the included temperature sensor
• Voltage-sense connection to compensate for voltage drops in the wiring
• Can be used as a stabilized power source or power supply
• Dry contact alarm terminal for external signaling

Three-stage, microprocessor-controlled battery charging

The charger controls the charging process using an IUoUo charging characteristic. After power-on, it starts in boost mode and supplies the battery with the required charging current. As soon as the set boost voltage is reached, the unit initially maintains this voltage at a constant level. It then switches to float mode and reduces the voltage to the level specified for trickle charging. For the Skylla-TG 24/50, the standard boost voltage is 28.5 V and the float voltage is 26.5 V. Both values can be adjusted within the specified ranges to meet the requirements of the battery in use. This makes the charger suitable for various battery applications, provided that the required charging parameters are set accordingly.

Two Outputs for Main and Starter Batteries

In addition to the 50 A main output, the 24 V version features a second output with a maximum of 4 A. This output is intended for charging or trickle charging a starter battery and operates at a slightly lower output voltage than the main output. This allows, for example, both battery systems in systems with a large service battery and a separate starter battery to be powered by the same charger. The second output is galvanically isolated from the main output.

Temperature Compensation for Adjusted Charging Voltage

The required charging voltage of a battery changes with its temperature. Therefore, a temperature sensor can be used that is attached directly to the battery. The charger automatically takes the measured temperature into account when regulating the output voltage. As the battery temperature rises, the charging voltage is reduced; as the temperature falls, it is increased accordingly. This is particularly relevant for sealed, maintenance-free batteries, where a consistently excessive charging voltage can contribute to overcharging and drying out. According to the datasheet, the temperature sensor is an integral part of the device.

Voltage Sense Compensates for Line Losses

At high charging currents, even slight cable resistance can cause a measurable voltage drop between the charger and the battery. The device therefore uses the Voltage Sense connection to measure the voltage directly at the battery terminals. The output voltage is adjusted accordingly to compensate for the voltage loss in the connecting cables. This compensation can be up to 2 V. This feature supports more precise charge control, particularly with longer cable lengths or high currents.

Customizable Charging Parameters and Additional Operating Modes

It offers several configuration options for different operating conditions. Internal DIP switches and potentiometers can be used to adjust, among other things, the boost and float voltages as well as the duration of the equalization charging mode. In addition, there is a permanent boost charging mode and a traction mode for corresponding battery applications. It can also be used as a stabilized power source without a connected battery.

Protection and Monitoring Functions

The integrated protection mechanisms include short-circuit protection as well as safeguards against excessive input voltage, excessive battery voltage, and elevated unit temperature. As the internal temperature rises, the unit first reduces the output current; under extreme conditions, it may shut down and resume operation once it has cooled sufficiently. A dry contact alarm also enables external signaling of a battery condition outside the specified voltage range.

Installation and Connection

The unit is intended for stationary installation in a dry, well-ventilated location. The cable run between the unit and the battery should be kept as short as possible to minimize cable losses. Ideally, the cable length should be less than 1.5 m with a recommended conductor cross-section of 10 mm²; for distances greater than 1.5 m, a cross-section of 16 mm² is recommended. The power connection, as well as the battery and other electrical connections, must be made in accordance with the specifications in the installation and operating instructions.

Technical Specifications

• Battery system: 24 V
• AC input voltage range: 90–265 V AC
• Rated supply voltage: 120–240 V AC
• Frequency: 45–65 Hz
• Power factor: 1
• Main battery charging current: 50 A
• Charging current at 110 V AC: 30 A
• Charging current for starter battery: 4 A
• Recommended battery capacity: 250–500 Ah
• Remote alarm: dry contact, 60 V / 1 A
• Cooling: forced cooling
• Protection class: IP21
• Ambient temperature: -40 to +50 °C
• Relative humidity: max. 95%
• AC connection: screw terminal, 2.5 mm² / AWG 6
• Dimensions: 365 × 250 × 147 mm
• Weight: 5.5 kg

Package Contents

1x Victron Energy Skylla-TG 24/50(1+1) GL 120-240V battery charger
1x Temperature sensor