High Efficiency, silent DC-DC converters to switch between 12, 24, and 48 volt systems. All units can be used in parallel if you need more power than a single unit can provide and adds system redundancy.

These devices are also referred to as buck / boost converters, switching power supplies, and dc-dc chargers. This page does not list MPPT charge controllers. If your intention is to charge a battery from solar power input, you should select an appropriate MPPT Charger instead.

Begin by choosing how many volts you need to convert from and to. Then select the maximum power output of the unit. If you know your equipment's watts, you can divide it by the voltage it runs at to determine how many amps it will draw.

The output voltage is fixed on some models, and variable on others. Variable output units have either a set-screw or bluetooth to adjust the output voltage.

Our converters can be used up to 100% of their rated output amps. The input is less if down-converting and more if up-converting. So it is important to size your power cables properly. It is still a wise idea to keep your constant loads at under 50% of the transformer's rated power to reduce heat and maximize equipment life.

Take the watts your machinery consumes, and divide them by the voltage, to get the amps output you need. If you need more amps than the unit provides, you can use two or more of the same model in parallel, as long as it is the same model, with the same settings configured.

Below are some additional considerations when choosing the best DC-DC Converter:

Isolated vs. Non-Isolated converters: For most uses, you get the best price and efficiency with non-isolated converters. They share a common negative. They may have 4 or 3 connectors. For models with three binding posts, such as the Victron Orion-TR series, you connect the negative of both your 24V and 48V systems to the same post, and you get a secondary positive with your other voltage of choice.

In comparison, an isolated converter creates a new circuit. Its output positive and output negative are not a part of the same circuit as the input. It is better suited for powering sensitive electronics and it is safer when stepping down from higher voltages because you get less points of contact to accidentally complete a circuit with.

You can always use an isolated transformer instead of a non-isolated unit, but they are more expensive and ironically slightly less efficient. Victron brand isolated converters are for example used for telecom and other critical DC equipment.

If you're running motors, batteries, DC air conditioners, or similar equipment, a larger size non-isolated converter will be your standard good choice.

What about 12 vs 13.8 Volts - 24 vs 27.1 Volts - 48 vs 54.4 Volts - What is the difference?

The higher 13.8 - 27.1 or  54.4 V helps with voltage drop on longer runs, and provides a boost to your pure DC equipment such as motors and heat pumps, reducing heat. These voltage setpoints coincide with a safe upper float voltage for keeping LFP batteries topped off without risk of overcharge.

It is important to note that the transformers do not have any charging algorithms and instead output a steady voltage up to the transformer's rated current output (amps). 4S, 8S, or 16S LFP banks can be relatively safely floated at these voltages which corresponds to 100% SOC. An example use scenario may be using a 48V ➔ 24V converter to maintain an auxiliary 24 volt battery from your 48V solar system’s main battery. Another example may be using a 12V ➔ 24V converter to charge an onboard 24 volt battery from the engine's 12 volt alternator.

Charger vs. not charger??

There is a difference. You can use a charger as a power supply no problem.

Chargers have the extra option of varying the voltage automatically to maintain a battery. They normally start by putting out a larger voltage to Bulk up the battery, then reduce the voltage to finish it. There can also be a third Float stage where the voltage is further reduced to a 'settled' voltage that the cells are happy to float at for long periods of time without damage.

Units designated as 'chargers' monitor the voltage of the battery they are attached to. They start by feeding a higher voltage to force feed the battery to take a faster charge at a higher current. Once the battery's full voltage is reached, the charger goes into float mode (which may be variable or fixed), where keeps the voltage is reduced and held steady. This completes the Bulk stage of charging if your charger has that setting.

A converter on the other hand constantly supplies the same fixed voltage. You can damage a battery by using it with a converter instead of a charger, if the converter's volts are higher than the recommended 'float' voltage of the battery.

Using a 12V out converter to charge a 12V LFP battery would not work, as its full voltage is 13.6V. At the same time, powering a router or modem that calls for a 12V DC input with a 13.8V out converter may fry it, depending on how it is built. So be sure to check the output volts in the picture of the selected converter, and match them to your needs.

Is there a difference between a converter and a transformer?

We have Transformer Tuesdays but the rest of the week we call them converters.

In all cases, we have the best solutions to help your DC-DC converting needs so if you need a second opinion to pick out the best one, just ask.