Monitoring
Victron SmartShunt 300A wiring diagram
300 A/50 mV battery shunt with Bluetooth and a VE.Direct port, no display — the smallest SmartShunt. Reads out through the VictronConnect app or a GX device; supports 6.5–70 V systems.
Wiring diagram
How the SmartShunt 300 is wired.
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Cable sizing for this example
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Installation notes
Before you install.
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Verified against the manufacturer's documentation (rev. 19 - 08/2026), checked 2026-10-01. Manufacturer documentation →
Which SmartShunt is covered?
This is the SmartShunt 300A/50mV, IP21. It measures one bank's current and state of charge and communicates through Bluetooth or VE.Direct; it has no display. The IP21 enclosure needs a dry mounting location. The manual's 300 A model measures 44 × 120 × 44 mm and uses M8 main bolts, maximum 10 N·m. Do not copy the smaller model's hardware specification when selecting lugs.
How do the power and return connections work?
Connect bank negative only to BATTERY MINUS. Connect every load and charging return to SYSTEM MINUS, through a common negative bus if needed. Earlier labels say LOAD MINUS. A chassis return connected on the battery side bypasses the measurement just as a directly connected charger does.
The red Vbatt+ lead supplies the electronics and measures voltage. Retain its supplied 1 A slow-blow fuse. The operating range is 6.5–70 V DC. This small fuse does not protect the bank cables, and 300 A is the shunt's measuring range, not a recommended battery fuse. Size the main circuit for its actual continuous and transient current, cable installation and fault protection.
What does Aux measure?
Aux can measure a second battery's voltage, series-bank midpoint voltage, or temperature with the specified sensor. It does not measure a second bank's current. Select one function and use the matching diagram in manual §3.5. The canvas shows the main shunt and voltage lead; Aux and the VE.Direct cable are additional connections.
What must be configured and checked?
Use VictronConnect to set the actual bank capacity, chemistry-related parameters and charged-voltage/tail-current settings. Synchronize to 100% only after the bank is actually full. With all loads and chargers off, check zero current; then switch on a known load and confirm discharge direction. A plausible voltage with missing current usually calls for a return-path check before changing calibration. See manual §§3–5 and the technical table in §11.
Fit check
Connect it to the rest of your system.
Describe your setup to draft a system with SmartShunt 300A connected. Review the selected parts and cable lengths, then edit the diagram in Crimp.
The model only picks parts and draws the connections. Every wire size and fuse rating still comes from Crimp's own sizing, never from the model.
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Technical reference
Specifications and terminal map.
Check the model, ratings and connection points against your own unit before choosing installation hardware.
Catalog specification
300 A/50 mV battery shunt with Bluetooth and a VE.Direct port, no display — the smallest SmartShunt. Reads out through the VictronConnect app or a GX device; supports 6.5–70 V systems.
Connection limits are listed in the terminal map. Use the manufacturer's documentation for the full specifications.
Terminal map
Catalog connection points, current direction and planning limits. Check the manufacturer's pinout and connector ratings before installation.
BATT −
negative · input
LOAD −
negative · output
B+ sense
signal · bidi
Sources and sizing method
Equipment specifications. Model details, ratings and terminal roles come from the catalog. Check your unit’s label and current manufacturer documentation for its exact revision.
Example sizing. Wire sizes and fuse ratings apply to the connected example, not a fixed cable size for this component. Set your actual equipment, current, lengths and installation conditions in Crimp before choosing hardware.
Read how the sizing worksNext step
Plan your installation with SmartShunt 300.
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