SmallBMS for LiTHIUM batteries - Victron Energy

Description

A simple and inexpensive alternative to the VE.Bus BMS

The smallBMS can replace the VE.Bus BMS in several applications. However, it is not suitable for use with MultiPlus and Quattro inverter/chargers with VE.Bus: it has no VE.Bus interface.

The smallBMS is designed to work with Victron Smart LiFePo4 batteries with M8 circular connectors.

The smallBMS has three outputs, just like the VE.Bus BMS.

Load disconnect output

The load output is normally high, and becomes floating in case of undervoltage risk on the cell(s) (default 2.8 V/cell, adjustable on the battery between 2.6 and 2.8 V per cell).

Maximum current: 1 A. The load output is short-circuit protected.

The load output can be used to control:

• A relay or contactor for high current
• The remote on/off input of a BatteryProtect, inverter, DC-DC converter or other loads. (An inverter or non-inverter remote on/off cable may be required. Please consult the detailed manual on our website).

Pre-alarm output

The pre-alarm output is normally floating, and becomes high in case of imminent undervoltage risk on the cell(s) (default 3.1 V/cell, adjustable on the battery between 2.85 and 3.15 V per cell). Maximum current: 1 A (not short-circuit protected).

The minimum delay between pre-alarm and load disconnect is 30 seconds.

Charger disconnect output

The charger (or alternator) disconnect output is normally high and becomes floating in case of imminent overvoltage or overheating. Maximum current: 10 mA.

The charger output is not suitable for powering an inductive load such as a relay coil.

The charger output can be used to control:

• The remote on/off of a charger.
• A Cyrix-Li charge relay.
• A Cyrix-Li-ct battery coupler.

System on/off input

The system on/off input controls both outputs. When off, both outputs will be floating, so that loads and chargers are turned off.

The system on/off has two terminals: Remote L, and Remote H.

A remote on/off switch or relay contact can be connected between terminals L and H.

It is also possible to switch terminal H to the positive battery terminal, or terminal L to the negative battery terminal.

Protects 12V, 24V and 48V systems
Operating voltage range: 8 to 70 VDC.