ChargeMaster 24/12-3

The Mastervolt ChargeMaster 24/12-3 is a fully automatic battery charger, designed for marine and mobile environments. It is intended to efficiently and safely recharge 24V battery banks using an advanced 3-stage+ charging algorithm.

The ChargeMaster 24/12-3 has dimensions of 234 x 132 x 60 mm (HxWxD). Its weight is 1.8 kg.

Yes, even when the batteries are not connected, the ChargeMaster 24/12-3 can provide a constant DC output, allowing you to power equipment such as lighting or refrigeration directly.

The 3-stage+ charging algorithm runs in three automatic phases:

BULK: The charger delivers its maximum current for a fast charge from 0 to 80 % of the battery's capacity.
ABSORPTION: The charger reaches its maximum charging voltage and the charging current slowly decreases until the battery is fully charged to 100 %.
FLOAT: This stage begins once the battery is fully charged. The battery remains in a fully charged state, compensating for self-discharge.

The ChargeMaster 24/12-3 has an IP23 protection rating. This means it is protected against solid objects larger than 12.5 mm and against rain falling at angles up to 60° from the vertical.

No, the ChargeMaster 24/12-3 does not have an on/off switch. To shut it down, you must cut the AC power. Charging will resume as soon as AC power is restored.

The ChargeMaster 24/12-3’s bright LED screen displays essential information such as charge current, charge voltage, charge stage, and battery level (or available capacity percentage in Ah). It also indicates the status of the MasterBus network communication.

The ChargeMaster 24/12-3 is compatible with a wide range of battery technologies, including lead-acid (flooded), AGM, Spiral, Gel, deep-cycle, and Mastervolt lithium-ion batteries (MLi).

Yes, the ChargeMaster 24/12-3 is compatible with the MasterBus network. This enables decentralized communication between the various devices in the Mastervolt system, as well as remote control and monitoring.

For Mastervolt gel batteries (MVG series), the minimum recommended capacity for the ChargeMaster 24/12-3 is 25 Ah. Always follow the manufacturer's instructions for your battery.

The ChargeMaster 24/12-3 is designed for indoor use only. It should preferably be mounted on a vertical wall, with the connection cables facing downward. Ensure at least 10 cm of free space around the device for proper air circulation and avoid placing it in the same compartment as batteries or directly above them due to corrosive fumes.

For maximum system efficiency, DC cables should be as short as possible. The minimum recommended cross-section for battery cables up to 3 meters (9 feet) in length is 4 mm² (10 AWG) for each of the three outputs. Use ring terminals on the battery side and cable ends on the charger side, crimped with an appropriate tool.

The recommended DC fuses for each of the three outputs of the ChargeMaster 24/12-3 are 15A. The battery positive cable must be fitted with a fuse and connected to the positive terminal of the battery bank.

Yes, for a secure installation, a residual current device (RCD) must be inserted into the ChargeMaster 24/12-3’s AC input circuit. The ground wire provides protection only if the ChargeMaster’s housing is connected to the safety ground.

In addition to the ChargeMaster itself, delivery typically includes:

A battery temperature sensor with cable and plug.DC wiring: 2 positive cables (red) and 1 negative cable (black).A MasterBus termination device.The user manual.Important safety instructions.

Installation must be carried out by a certified electrician. All electrical systems (AC and DC) must be disconnected from any power source during installation. It is critical to avoid short circuits or reverse polarity, as this can seriously damage batteries, the ChargeMaster, wiring, and accessories.

The warranty for the ChargeMaster 24/12-3 may be voided if work is performed that does not comply with the guidelines, instructions, and specifications contained in the user manual. Mastervolt guarantees that the unit was built according to applicable standards, but any deviation from the instructions may result in damage or failure to meet specifications, thereby voiding the warranty.

Yes, the ChargeMaster 24/12-3 is equipped with temperature compensation. By installing the included battery temperature sensor, charging voltages are automatically adjusted to ambient temperatures. This prevents overcharging or excessive gassing, thereby extending the life of your batteries.