Meet the Victron SmallBMS for Smart LiFePO4 Batteries with M8 connectors—the compact, low-cost alternative to the VE.Bus BMS. This smallBMS can replace the VE.Bus BMS in several applications, but it is not suitable for VE.Bus MultiPlus and Quattro inverter/chargers because it has no VE.Bus interface. Specifically designed for Victron Smart LiFePo4 batteries with M8 circular connectors, it delivers essential protection and precise control while keeping installation simple and affordable.
Key capabilities
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Three outputs for comprehensive protection: Load Disconnect, Pre-alarm, and Charger output, mirroring the essential functions of a VE.Bus BMS.
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Load Disconnect is normally high and becomes free-floating if a cell drops below the set threshold (default 2.8 V per cell, adjustable 2.6–2.8 V per cell). Maximum current: 1 A. Not short-circuit protected. Ideal for driving a high‑current relay or contactor, or for remote on/off control of loads such as inverters or DC‑DC converters.
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Pre-alarm is normally free-floating and goes high when imminent cell under‑voltage is detected (default 3.1 V per cell, adjustable 2.85–3.15 V per cell). Maximum current: 1 A (not short‑circuit protected). Minimum 30 seconds between pre‑alarm and load disconnect to allow safe transitions.
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Charge Disconnect is normally high and becomes free-floating on imminent cell overvoltage or over‑temperature. Maximum current: 10 mA. Not suitable for inductive loads. Use it to control the remote on/off of a charger, a Cyrix-Li-Charge relay, or a Battery Combiner System on/off input.
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System on/off input controls both outputs. The two terminals Remote L and Remote H accept a remote switch or relay between them; alternatively, H can be switched to battery plus and/or L to battery minus. When the system is off, both outputs become free-floating, turning off loads and chargers.
Electrical compatibility and indicators
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Protects 12 V, 24 V and 48 V systems with an operating range of 8 to 70 V DC.
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LED indicators: Load ON (blue) shows when the Load output is high (cell voltage > 2.8 V, adjustable on the battery). Temp or OVP (red) indicates charger output has freed due to cell over temperature (>50°C), cell under temperature (<5°C), or cell over voltage.
Designed for Victron Smart LiFePo4 batteries with M8 circular connectors, the SmallBMS gives you robust protection, flexible control, and straightforward installation at a fraction of the cost of other bus systems. It enables reliable load isolation, proactive cell‑voltage monitoring, and controlled charging actions across 12 V, 24 V and 48 V configurations.
Please contact your dealer for any returns, repairs or support issues related to this product.
