A lithium battery holds an almost flat voltage until it's nearly empty, so a gauge that only reads voltage can read full long after the pack has been drawn down. DualPRO's lithium battery fuel gauges solve that with a current transducer (CT), which tracks the amp-hours going in and out. Here's how the five DualPRO gauges we carry differ and which one fits your setup.
The five gauges at a glance
| Gauge | Display | Batteries | Voltage |
|---|---|---|---|
| BFGRLITH | Round, single | Lithium (LiFePO4) | Configurable for 12V, 24V, 36V or 48V |
| BFGVLITH | Vertical rectangle, single | Lithium (LiFePO4) | Configurable for 12V, 24V, 36V or 48V |
| BFGHLITH | Horizontal rectangle, single | Lithium (LiFePO4) | Configurable for 12V, 24V, 36V or 48V |
| BFGDUALLITH | Dual, round, marine | Two lithium banks, two CTs | 36V and 12V, or 24V and 12V |
| BFGDUALCOMBO | Dual, round, marine | Listed for lithium and AGM / flooded batteries | 36V and 12V, or 24V and 12V |
The single gauges include one CT and the BFGDUALLITH includes two; DualPRO doesn't list a CT for the BFGDUALCOMBO.
Single gauges: round, vertical or horizontal
The three single gauges work the same way and differ only in shape. Each one includes a CT, can be configured for a 12V, 24V, 36V or 48V lithium pack, and shows the pack level on a 9-LED array. A red low-battery LED flashes a warning and stays on when the pack needs charging, and the LEDs also show charging progress. DualPRO says these gauges can also be configured for lead-acid and AGM batteries.
- BFGRLITH: a round face, about 2.25 in across, that fits a 2 in round cutout. This is the usual pick for a dash or console with round gauges.
- BFGVLITH and BFGHLITH: 2.1 x 1.25 in rectangular faces, one upright and one sideways, for a tight panel.
DualPRO lists these for golf carts, LSVs, utility vehicles, aerial lifts, lift trucks, floor scrubbers and boats.
Dual gauges: trolling bank plus cranking battery
On a bass boat with a 24V or 36V trolling motor and a separate 12V cranking battery, a dual gauge shows both on one round display.
- BFGDUALLITH: both sides read lithium, and it comes with two CTs, one per bank. Choose it if the trolling bank and the 12V battery are both lithium.
- BFGDUALCOMBO: DualPRO lists it for use with lithium and AGM or flooded (FLA) batteries. It's the one to ask about if your trolling bank is lithium and your cranking battery isn't; confirm which side reads which chemistry in the instructions before you install.
Both cover 36V plus 12V or 24V plus 12V. DualPRO's spec sheet lists a 1.065 x 1.58 in panel cutout for the dual gauges. Check the instructions before you cut.
Installing the current transducer
The CT is a sensor that a battery cable passes through. DualPRO lists the CT opening at 0.75 x 0.42 in, so your battery cable must fit through that slot, and the single gauges have a 13 ft cable. Measure your cable (including its insulation) before you order. DualPRO offers cable extenders for longer runs, but we don't stock them.
The PROView Link app
The gauges work with DualPRO's free PROView Link app for Apple and Android, which lets you check the battery from your phone over Bluetooth, configure the battery, and receive over-the-air updates. DualPRO's chargers that support PROView Link, such as the Eagle HF ES800, use the same app.
Which gauge for which setup
| Your setup | Gauge |
|---|---|
| 36V or 48V lithium golf cart or LSV with a round dash hole | BFGRLITH |
| Lithium pack in a tight rectangular panel, such as a lift or utility vehicle | BFGVLITH or BFGHLITH |
| Boat with a 24V or 36V lithium trolling bank and a 12V lithium cranking battery | BFGDUALLITH |
| Boat that mixes lithium with AGM or flooded batteries (24V or 36V plus 12V) | BFGDUALCOMBO (confirm the setup in its instructions) |
| Boat with a single 12V lithium trolling battery | BFGRLITH set for 12V |
For any other mix, such as two 12V batteries, ask us before you order.
Setting it up
After the gauge is wired and the battery cable runs through the CT, DualPRO has you configure the battery in the PROView Link app: so the display matches your pack. The gauge then tracks the state of charge as the pack discharges and recharges, and adjusts itself while charging is in progress.
Gauge or shunt monitor?
A gauge gives you a permanent display you can read at a glance at the helm or on the dash. A shunt-based monitor such as the Victron SmartShunt has no display of its own and is read in an app. If that's what you're weighing up, see SmartShunt for lithium trolling motor and kayak batteries.
FAQ
Why does a lithium gauge need a current transducer?
Because voltage alone says little about how full a lithium pack is. The CT counts amp-hours in and out, so the gauge follows the actual state of charge.
Can a DualPRO lithium gauge read an AGM or lead-acid battery?
DualPRO says its lithium gauges can also be configured for lead-acid and AGM batteries. For a boat that pairs lithium with AGM on one display, the BFGDUALCOMBO is made for that mix.
How far can the gauge sit from the battery?
DualPRO lists a 13 ft cable on the single lithium gauges. Plan the route from the battery to the dash before you mount it.
What warranty do DualPRO gauges have?
DualPRO lists a 1-year factory warranty on these gauges.
Which charger pairs with these gauges?
Any charger suited to your batteries. For lithium on a boat, see charging lithium trolling motor batteries with DualPRO.
See the gauges and chargers in our DualPRO range.