Battery Equivalents and Replacements

ProMariner 44021 ProSportHD 20 Plus 3-Bank Battery Charger

ProMariner 44021 ProSportHD 20 Plus 3-Bank Battery Charger is a very popular lead-acid 20A battery charger intended for charging 12V, 24V, and 36V batteries and battery packs in various combinations.

As such, ProMariner 44021 ProSportHD 20 Plus 3-Bank Battery Charger is commonly used on boats, yachts, RVs, off-the-grid, and other similar applications and installations where a fully automatic on-board battery charger is required.

Published: June 9, 2023.

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ProMariner 44021 ProSportHD 20 Plus Features and Specifications

ProMariner 44021 ProSportHD 20 Plus 3-Bank Battery Charger is a relatively compact unit featuring physical dimensions of 7.9 x 12.8 x 2.9 inches (~20 x 32.5 x 7.4 cm) and weighing 7.8 pounds (3.53 kg).

Also, it comes with 6' (~183 cm) long cables with inline fuses and accepts 110-120V 60Hz AC power.

battery cables

Note: ProMariner ProSport HD20Plus Global (model 44029) is a similar 3-bank battery charger that accepts 100-240V AC 50-60Hz - hence the "Global" as part of its label.

ProMariner 44021 ProSportHD 20 Plus battery charger features an IP67 water protection level.

This battery charger is intended for charging only lead-acid batteries (wet/flooded, Gel-Cell, AGM) and is unsuitable for charging lithium batteries. But it can be used to charge 12V, 24V, and 36V batteries.

For example, the charger can be connected to three batteries and charge them with 20A total. These three batteries may be connected as follows:

  • three individual 12V batteries,
  • one 12V battery and one 24V battery (two 12V batteries connected in series),
  • one 36V battery (three 12V batteries connected in series).

This flexibility is just one of many reasons why the ProMariner 44021 ProSportHD 20 Plus is one of the most popular 3-Bank onboard battery chargers.

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ProMariner 44021 ProSportHD 20 Plus 3-Bank Battery Charger also comes with other features required for an onboard charger.

One of such very interesting features is so-called "Distributed-On-Demand" charging - the battery charger features a total charging current of 20 Amps, which is distributed across the banks depending on the requirements.

This allows the battery charger to charge unevenly dimensioned and charged batteries faster - however, if You intend to charge a uniform and balanced battery pack consisting of three exactly the same batteries, this feature doesn't help.

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The housing of the charger is very strong and ensures good passive cooling. However, it is highly recommended to mount the charger (and the batteries) in a well-ventilated area to prevent the buildup of various gasses and improve the cooling indirectly.

status panel

A control panel provides all required information in a single place, including charging and battery status.

ProMariner 44021 ProSportHD battery charger is very easy to set, use, and maintain; however, when the unit arrives, be sure to read the manual/Owner's Guide thoroughly, especially Safety and Battery Connections sections. If required, one can also store the Owner's Guide near the unit to "refresh" the memory occasionally.

ProMariner 44021 ProSportHD battery charger comes with a 3-year limited warranty. Also, considering all its features, it comes at a rather affordable price. And no, it is not a cheap unit ;)

For more reviews and recommendations, feel free to check the ProMariner 44021 ProSportHD 20 Plus 3-Bank Battery Charger Amazon link (link opens in the new window).