Mastervolt DC Master 48/12-20 DC-DC Converter

The Mastervolt DC Master 48/12-20 is a non-isolated converter. This means there is no galvanic isolation between the 48V input and the 12V output. In a non-isolated converter, the negative grounds of the input and output are common.

This makes it suitable for installations where the 48V circuit and the 12V circuit share the same negative ground. Conversely, an isolated converter (such as certain models in the DC Master range labeled 'isolated') electrically separates the two circuits, which may be necessary to avoid ground loops or for safety reasons with sensitive equipment.

Yes, this is entirely possible. The Mastervolt DC Master 48/12-20 is designed to convert an input voltage of 48V into a stabilized output voltage of 13.6V. This 13.6V output is ideal for maintaining the charge of a 12V battery (lead-acid, AGM, or gel type) or for directly powering 12V consumers.

It can therefore perfectly serve to charge an auxiliary 12V battery from a 48V propulsion battery bank, for example on a sailboat or an electric boat.

Installing the DC Master 48/12-20 requires a few essential precautions:

Power off: Ensure the power source (48V battery) is turned off or disconnected before starting the installation.Disconnect loads: Verify that no devices are connected to the batteries during installation to avoid any risk.Check voltages: Confirm that the battery voltage matches the converter's input voltage (48V) and that the output voltage (13.6V) is suitable for your load.Install a fuse: Add a fuse on the positive cable, as close as possible to the 48V battery.Mounting: Choose a cool, dry, and well-ventilated location. Use the provided mounting bracket to clip the converter in place.Wiring order: Connect the input wires (48V side) first, then the output wires (12V side).

The Mastervolt DC Master 48/12-20 can provide a continuous output current of 20A. It can also deliver a peak current of 24A for a maximum duration of 2 minutes, which is useful for starting equipment with a high inrush current.

The Mastervolt DC Master 48/12-20 has a nominal output power of 272W. This corresponds to an output voltage of 13.6V multiplied by a continuous current of 20A. Its maximum output power reaches 326W (13.6V x 24A for 2 minutes).

Absolutely. The Mastervolt DC Master 48/12-20 is specifically designed for this type of application. On modern cruising sailboats or electric propulsion boats, it is common to have a 48V service battery bank. This converter reliably and stably powers all your 12V equipment (lighting, autopilot, navigation instruments, VHF, etc.) from this 48V source.

The Mastervolt DC Master 48/12-20 accepts an input voltage range of 40 to 62V to deliver its full output power. It can withstand without damage an input voltage range of 0 to 65V DC. Below 40V or above 62V, the output may no longer be stabilized or the converter could go into safety mode.

The Mastervolt DC Master 48/12-20 input and output connections are Faston type (quick-connect terminals). This makes cable connection easier. The product is supplied with the necessary Faston connectors.

Yes, the Mastervolt DC Master 48/12-20 is a stabilized converter. This means its 13.6V output voltage remains constant and precise, even if the input voltage fluctuates within its normal operating range (40–62V). This stabilization is essential to protect sensitive electronic equipment connected at the output.

Yes, absolutely. The Mastervolt DC Master 48/12-20 is perfectly suited to power a 12V autopilot. Its stabilized output voltage of 13.6V and its ability to supply up to 20A continuously (and 24A peak) are suitable for most autopilots, which often draw high currents during manoeuvres. Just ensure that your autopilot's consumption does not exceed 20A continuously.

The Mastervolt DC Master 48/12-20 comes complete with everything needed for installation. The package includes:

The DC-DC converter itselfA mounting bracket (clip) for easy wall installationMounting screws for the bracketFaston connectors for cable connections

Yes, the Mastervolt DC Master 48/12-20 is compatible with 48V lithium batteries, provided the battery voltage remains within the converter's operating range (40-62V). Since lithium batteries have a wider voltage range than lead-acid batteries, ensure your lithium battery's maximum charge voltage does not exceed 62V. In most cases, this is compatible.

Yes, the Mastervolt DC Master 48/12-20 can power a 12V refrigerator. Most marine refrigerators draw between 3 and 8A during operation, with a peak at compressor start-up. With its 20A continuous and 24A peak output, this converter can handle this type of load without issue. Ensure the total power of connected equipment does not exceed 272W.

Mounting the Mastervolt DC Master 48/12-20 is straightforward thanks to the supplied bracket. Follow these steps:

Select a cool, dry, and well-ventilated location.Use the mounting bracket to mark the positions for the three mounting holes.Drill 3.5 mm diameter holes.Secure the bracket with the supplied screws.Snap the converter onto the bracket.Ensure adequate clearance around the unit for proper airflow and natural cooling.

The part number (SKU) for the Mastervolt DC Master 48/12-20 is 81400800. This code uniquely identifies it within the Mastervolt range and ensures the correct reference is ordered.