Distribution
Victron VE.Bus BMS V2 wiring diagram
Control-level BMS for original Victron Lithium Battery Smart. Requires a compatible VE.Bus inverter or inverter/charger: battery negative is obtained through VE.Bus, with no separate negative power terminal. Battery+ uses a 1 A fused lead; load and charge control wiring is separate.
- Continuous draw
- 0 A
Wiring diagram
How the VE.Bus BMS is wired.
Open this example in Crimp to use your own parts and cable lengths. Review the assumptions and installation notes as you adapt the circuit.
Cable sizing for this example
Use the diagram as a starting point for your installation. Replace the example equipment and cable lengths with your own, and check the connections against your exact model's instructions.
3 m one way
12 V system
- Wire
- 1.5 mm² · 16 AWG
- Example fuse
- 1 A
- Design current
- 0.0 A
- Voltage drop
- 0.0%
Sized against ABYC E-11. The design current is the part's continuous draw. The length is one way; voltage drop includes an equal-length return.
Run-length and manufacturer assumptions
The editable example uses 3.048 m (10 ft) runs unless a shorter run is stated. Metric overviews round these to 3 m. Adapt the parts and lengths to your installation before choosing cable and protection.
Supporting parts
- 6.1 m total of 1.5 mm² (16 AWG) marine cable
- Terminations for 1.5 mm² cable, matched to the equipment's screw terminals, leads or studs
- 1 A fuse and holder on the positive run
- Heat-shrink, strain relief and terminal boots sized to the cable
Check stud sizes, fuse type, run length and how warm the space gets against the gear you actually have before you order.
Installation notes
Before you install.
Open a question for model-specific guidance and sources.
Verified against the manufacturer's documentation (rev. Rev 07 — 06/2025), checked 2026-10-01. Manufacturer documentation →
Which system can use VE.Bus BMS V2?
This BMS protects Victron Lithium Battery Smart, the original non-NG battery family, in a system with a compatible VE.Bus inverter or inverter/charger. It is not the VE.Bus BMS NG. The V2 manual, printed pages 4–9, supplies the installation and firmware requirements.
It carries no main battery current. Battery power goes to the inverter/charger and protected DC distribution independently of this small controller.
Why is there only a positive supply terminal?
The drawing's + represents Battery+, supplied through the manual's 1 A inline fuse with at least 0.75 mm² (16 AWG) wire. The BMS has no separate battery-negative power connection. It obtains negative through VE.Bus and cannot operate without the connected VE.Bus device.
Connect the inverter/charger's VE.Bus port to the BMS MultiPlus/Quattro port. Daisy-chain the batteries' BMS cables, then connect the first and last cable to the BMS. Neither VE.Bus nor this battery-control chain is represented by the single positive terminal on the simplified drawing.
How are the other loads and chargers controlled?
Load disconnect is a normally-high source output rated 1 A; Charge disconnect is rated only 10 mA. Both become free-floating to withdraw permission. These are control outputs, not high-current load terminals or general-purpose relay-coil supplies. Confirm the receiving input's required polarity and interface cable.
Compatible solar chargers can be controlled through a GX device with DVCC enabled. Other chargers and DC loads need the documented remote input or external switching arrangement. Uncontrolled devices can continue charging or discharging after the BMS requests a stop.
The remote L/H connection controls system on/off. GX-Pow and Aux-In support keeping a GX device powered for monitoring; they are separate 1 A circuits, not substitutes for the missing main negative terminal.
Which setup details are model-dependent?
Printed page 5 recommends VE.Bus firmware xxxx489 or later and explains the assistant requirement for earlier supported versions. Older processors numbered 19XXXXX or 20XXXXX are unsupported. Verify the inverter's generation before commissioning.
The supplied mains detector is not required for the listed new-style MultiPlus 12/1600/70 or 12/2000/80, MultiPlus-II, Quattro-II or inverter models. Other supported inverter/chargers can require it for recovery when AC returns after low-cell shutdown; follow the exact model instructions.
Check battery detection, VE.Bus communication, remote off and charger/load permission behavior before use. The drawing omits those control circuits, the optional mains detector and AC protection. The small fused Battery+ lead alone is not a complete BMS installation.
Fit check
Connect it to the rest of your system.
Describe your setup to draft a system with VE.Bus BMS V2 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
Control-level BMS for original Victron Lithium Battery Smart. Requires a compatible VE.Bus inverter or inverter/charger: battery negative is obtained through VE.Bus, with no separate negative power terminal. Battery+ uses a 1 A fused lead; load and charge control wiring is separate.
- Continuous draw
- 0 A
Terminal map
Catalog connection points, current direction and planning limits. Check the manufacturer's pinout and connector ratings before installation.
+
positive · input
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. Sized against ABYC E-11. Boats built to UK or EU rules answer to ISO 13297 — check these figures against it before you build. Results use the example current and run length shown above. Set your actual equipment, lengths and installation conditions in Crimp before choosing hardware.
Read how the sizing worksNext step
Plan your installation with VE.Bus BMS.
Open this example as a new project, or add this component to your existing diagram. Use your equipment and cable lengths to review the sizing.
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