The Victron SmartShunt and BMV-712 are the two battery monitors in the current Victron range. Both measure the same thing — how much energy is flowing in and out of your battery — but they do it with different form factors and features. This guide helps you choose the right one.
Quick Answer
The SmartShunt is app-only (no display), compact, cheaper, and the newer design. The BMV-712 adds a physical display panel and a programmable relay. Choose the SmartShunt if you're comfortable using your phone or have a GX device with a screen. Choose the BMV-712 if you want a dedicated display mounted in your dashboard or panel.
Feature Comparison
| Feature | SmartShunt | BMV-712 |
|---|---|---|
| Shunt rating | 500A / 50mV | 500A / 50mV |
| Built-in Bluetooth | Yes | Yes |
| Physical display | No (app only) | Yes (wired display panel) |
| VE.Direct port | Yes | Yes |
| VE.Smart Networking | Yes | Yes |
| Temperature sensor included | Yes (built-in on some models) | Optional (sold separately) |
| Programmable relay | No | Yes (built into display) |
| Midpoint voltage monitoring | Yes (500A model) | Yes |
| Physical size (shunt) | Very compact | Same shunt, larger with display |
| Accuracy | ±0.5% | ±0.5% |
How They Work
Both devices use a shunt resistor connected in the battery's negative cable. By measuring the tiny voltage across this precision resistor, they calculate the current flowing in or out of the battery. A microprocessor tracks cumulative current over time to calculate:
- State of Charge (SOC) — percentage of battery capacity remaining
- Voltage — battery terminal voltage
- Current — amps flowing in (charging) or out (discharging)
- Power — watts (voltage × current)
- Consumed Ah — amp-hours used since last full charge
- Time remaining — estimated hours until battery is empty at current draw
The SmartShunt Advantage: Simplicity
The SmartShunt is just the shunt unit with a small PCB — no display, no cables to a panel. It mounts at the battery, connects via two wires (to battery positive and the load side of the shunt), and you monitor everything via the VictronConnect app on your phone or tablet.
Benefits:
- Cheaper: No display to manufacture, so the price is lower.
- Simpler installation: No need to route a cable from the battery to a display panel.
- More flexible: Monitor from anywhere within Bluetooth range (up to 10m typical).
- Cleaner dashboard: No additional panel cutout required.
If you have a Cerbo GX with a GX Touch display, the SmartShunt data appears on the GX screen alongside your solar, inverter, and other system data. This makes a dedicated BMV display redundant.
The BMV-712 Advantage: Always-On Display
The BMV-712 includes a wired display panel that shows battery data at a glance — no phone needed, no app to open, no Bluetooth connection to establish. It's always on and always visible.
Benefits:
- Instant visibility: Glance at the panel to see SOC, voltage, and current without picking up a phone.
- Physical relay: The display unit includes a programmable relay that can trigger alarms, start generators, or control loads based on battery conditions (low voltage, low SOC, high voltage, etc.).
- No phone dependency: Works independently of any smartphone or tablet.
- Familiar interface: Buttons to scroll through readings — straightforward for users who aren't app-savvy.
Bluetooth Range
Both devices have Bluetooth, but the SmartShunt relies on it entirely for monitoring. In practice:
- SmartShunt: Bluetooth range is typically 5–10m through walls and obstacles. In a campervan, this easily covers the distance from under-seat batteries to anywhere in the van. In a larger boat, Bluetooth may not reach from the engine room to the cockpit.
- BMV-712: The display is wired (up to 10m cable), so Bluetooth range is less important — you have the physical display regardless.
Temperature Monitoring
Battery temperature data is important for accurate charging — especially for lead-acid batteries that need temperature-compensated charge voltages.
- SmartShunt IP65: Has a built-in temperature sensor in the shunt unit. Temperature data is shared automatically via VE.Smart Networking with compatible charge controllers.
- SmartShunt (standard): No built-in temperature sensor. You can add a Smart Battery Sense for temperature.
- BMV-712: Temperature sensor sold separately (an optional cable with a ring terminal sensor).
Which Should You Buy?
Choose the SmartShunt if:
- You're comfortable monitoring via the VictronConnect app
- You have a GX device with a display (Cerbo GX + GX Touch)
- You want the simplest, cheapest, most compact installation
- You don't need a programmable relay
- You're building a new system and want the most modern option
Choose the BMV-712 if:
- You want a permanent, always-visible display
- You need the built-in programmable relay (for alarms, generator start, etc.)
- You prefer not to rely on a smartphone for monitoring
- Your installation is on a larger boat where Bluetooth range may be insufficient
Can You Use Both?
No — you only need one battery monitor per battery bank. Both the SmartShunt and BMV-712 use the same 500A shunt and measure the same data. There's no benefit to having both.
Summary
The SmartShunt is the better choice for most new installations — it's cheaper, simpler to install, and provides all the same data via the VictronConnect app or a GX device. The BMV-712 is worth the extra cost only if you specifically need a permanent physical display or the built-in programmable relay. Both are excellent battery monitors with identical accuracy and measurement capability.
