DualPRO on-board chargers give every 12V battery on the boat its own charging output, called a bank. Picking the right one comes down to three questions: how many 12V batteries you have, how many amps you want per battery, and what kind of batteries they are. This guide walks through all three for the DualPRO models we carry: the Professional Series PS1 to PS4, their AutoProfile versions, and the Sportsman HF SS2HF to SS4HF.
Step 1: count your 12V batteries
Professional Series and Sportsman HF banks are 12V outputs. On a 24V, 36V or 48V trolling motor, the batteries are 12V units wired in series, and DualPRO's multi-bank chargers put one bank on each of those batteries so they all charge at the same time. Add one more bank if you want the same charger to look after the cranking battery.
| Your setup | 12V batteries | Banks | Professional Series (15A per bank) | Sportsman HF (10A per bank) |
|---|---|---|---|---|
| One battery: a 12V trolling motor battery or a single cranking battery | 1 | 1 | PS1 or PS1AUTO | None in this range |
| 12V trolling motor plus a cranking battery, or a 24V trolling motor on its own | 2 | 2 | PS2 or PS2AUTO | SS2HF |
| 24V trolling motor plus a cranking battery, or a 36V trolling motor on its own | 3 | 3 | PS3 or PS3AUTO | SS3HF |
| 36V trolling motor plus a cranking battery, or a 48V trolling motor (four batteries) | 4 | 4 | PS4 or PS4AUTO | SS4HF |
DualPRO describes the PS3AUTO the same way: built for a two-battery 24V trolling motor with a cranking battery, or a three-battery 36V trolling motor. A 48V motor on four 12V batteries uses all four banks of a PS4 or SS4HF, so there is no bank left over for a cranking battery.
Step 2: 15 amps or 10 amps per bank
Every Professional Series bank delivers 15A. Every Sportsman HF bank delivers 10A. Each bank is independent, so a four-bank PS4 can put 15A into each of its four batteries at once (60A total), and an SS4HF puts 10A into each (40A total).
A rough way to compare: divide the amp-hours you need to put back by the amps per bank. If a 100Ah battery is half empty, that's about 50Ah to replace. At 15A that's roughly 3.3 hours of bulk charging; at 10A it's roughly 5 hours. The charger then spends extra time on the finishing stage, and real-world losses add more, so treat these numbers as a floor, not a promise. If you fish early mornings and recharge overnight, either rate usually covers it. If you have big batteries and short turnarounds, 15A per bank gives you more margin.
Step 3: match the battery type
- Wet cell (flooded) or AGM only: the standard Professional Series (PS1, PS2, PS3, PS4). DualPRO lists these PROVolt models for Wet Cell and AGM batteries.
- Lithium (LiFePO4), now or later: an AutoProfile model (PS2AUTO and the rest), which detects lithium, AGM or flooded batteries on each bank, or a Sportsman HF, where you select lithium, wet cell or AGM for each bank yourself.
- Mixed, such as a lithium trolling bank with an AGM cranking battery: either AutoProfile or Sportsman HF works, because each bank is set to its own battery.
The details, including what happens when you switch from AGM to lithium, are in our guide to charging lithium trolling motor batteries with DualPRO.
What if my trolling motor runs on one 24V, 36V or 48V battery?
A single 36V lithium pack, for example, isn't a set of 12V batteries, so a 12V-per-bank charger doesn't fit it. For that, DualPRO makes the Eagle HF ES800 marine chargers: ES0800-24V003 for 24V, ES0800-36V003 for 36V and ES0800-48V003 for 48V. DualPRO's spec sheet says these work with a single 24V, 36V or 48V battery, or with batteries in series when paired with its B.O.S. (Battery Optimization System). Our Eagle HF ES800 guide explains the different versions.
Professional Series or Sportsman HF?
Beyond 15A versus 10A per bank, the two lines differ in size, weight and cable length: a Sportsman HF is much lighter for the same number of banks, and it comes with longer cords. The side-by-side numbers are in DualPRO Professional Series vs Sportsman HF.
What every model here has in common
- IP67 waterproof, rated for fresh and salt water
- ISO 8846 marine standard, ignition protected to US Coast Guard 33 CFR 183.410
- Fully automatic multi-stage charging with a maintenance mode
- Ring-terminal DC leads: 5 ft on Professional Series, 6 ft on Sportsman HF
- A 3-year warranty from DualPRO
Mounting and wiring
These are on-board chargers: they mount on the boat, the DC leads stay connected to the batteries, and you plug the AC cord into shore power at the dock or at home. A few things to plan before you drill:
- Lead length. The DC leads are 5 ft on Professional Series and 6 ft on Sportsman HF, so mount the charger within reach of every battery it charges.
- One bank, one battery. Each bank's leads go to the terminals of its own 12V battery, including the batteries in a series trolling string. Follow the wiring diagram in the DualPRO manual for your model.
- Leave it plugged in. All of these chargers are fully automatic and drop into a maintenance mode once the batteries are full, so the boat can stay on the charger between trips.
- Read the lights. LEDs show each battery's state of charge, and the chargers display diagnostic codes if something is wrong on a bank.
FAQ
Do I need a bank for my cranking battery?
Only if you want this charger to charge it. If you do, count it as one more 12V battery when you pick the number of banks.
Can a DualPRO charger charge a lithium battery?
The AutoProfile and Sportsman HF models can, and so can the Eagle HF ES800, where you set lithium in the PROView Link app. The standard Professional Series models are listed for wet cell and AGM batteries.
How do I pick between PS3 and PS3AUTO?
They have the same three 15A banks. Choose the PS3AUTO if any battery on the boat is lithium, or might be one day. If you only run flooded or AGM batteries, the PS3 does the job.
See every model in our DualPRO range, or read our general battery charger buying guide.