2. Introduction
2.1. General description
The Smart BMS 12-200 is an all-in-one battery management (BMS) system for Victron Lithium Battery 12,8V Smart batteries available with a nominal voltage of 12.8V in various capacities. This is the safest of the mainstream lithium battery types. The maximum number of batteries in one system is 20, which results in a maximum energy storage of 84kWh in a 12V system. It has been specifically designed for 12V systems with a 12V alternator such as in vehicles and boats.
It combines a Current Limiter, Battery Combiner and Battery Protector in a robust and compact solution and lets you safely connect any size 12V alternator (and starter battery) through its dedicated alternator connection. At the same time, it protects the alternator (and wiring), provides alternator current limiting and one-way traffic from the alternator into the battery, this so any size alternator (and starter battery) can be safely connected to the lithium battery and the starter battery is protected from excessive discharge.
A dedicated power System+ port allows the direct connection of DC loads, chargers or inverters and inverter/chargers to charge the lithium battery or to supply DC loads with up to 200A. The power port works in both directions and the BMS ensures that it will cut-off loads in case of imminent cell under voltage to protect the battery and also enables charging through this port.
The Smart BMS 12-200 monitors and protects each individual battery cell within the battery and will disconnect the alternator, charge sources or DC loads in case of low/high battery cell voltage or high temperature.
The BMS is equipped with Bluetooth for monitoring and configuration via our VictronConnect app. This includes Instant Readout, which allows key values, including notifications for warnings, alarms and errors, to be read and displayed in real time without requiring a paired connection to the BMS, enabling diagnostics at a glance. A programmable remote on/off function defines what is controlled by the Remote on/off terminals: Alternator/Starter Batt+ & System+, Alternator/Starter Batt+ only or switch everything, including the BMS, off. A pre-alarm contact allows a warning signal to be issued before the BMS disconnects the batteries from the system.
2.2. Features and functionality
Alternator/Starter Batt+ port alternator and battery protection
The input current on the Alternator/Starter Batt+ port is electronically limited to approximately 90% of the fuse rating. A 100A fuse, for example, will therefore limit the input current to approximately 90A. (For fuse ratings and corresponding current limit please see the table in the Installation chapter).
Current can flow to the lithium battery only if the input voltage (corresponds to the voltage of the starter battery) exceeds 13V. In addition, no current can flow back from the lithium battery to the starter battery, which prevents the lithium battery from being deeply discharged.
Choosing the right fuse will also:
Protect the lithium battery against excessive charge current (important in case of a low capacity battery).
Protect the alternator against overload in case of a high capacity lithium battery bank (most 12V alternators will overheat and fail if running at maximum output during more than 5 minutes).
System+ power port to connect loads and additional chargers
The System+ port can be used to either charge or discharge the lithium battery (i.e. via an additional charger, an inverter or inverter/charger connected directly to this port) with a maximum continuous current of 200A in both directions.
The BMS interrupts the battery charge/discharge if there is a risk of imminent cell under- or overvoltage or low/high temperature. Charging via System+ is also stopped when set Battery charge limit has been reached. The input will turn on again when the battery voltage is 0.5V below the battery charge limit for 10 (consecutive) seconds.
Remote on/off terminal
The Remote on/off terminal can be used to interrupt charging via the Alternator port and charging and discharging via the System+ port or interrupt charging via the Alternator port only while the BMS functionality will remain active regardless of the remote on/off state.
Depending on the Remote on/off function setting made via the VictronConnect app, it can also be used as system on/off switch (Charge and Load disconnect port will also be disabled) either by using a physical switch or a relay contact between L and H terminal or by using the soft switch in the VictronConnect app. Alternatively, terminal H can be switched to battery plus, or terminal L can be switched to battery minus.
Note
Note that it is mandatory to install either an on/off switch between L and H of the remote on/off terminal or the wire loop (default) for correct operation. Alternatively, terminal H can be switched to battery plus or terminal L to battery minus.
LED indicators
The BMS has a number of LED indicators that show the status of the BMS and the various inputs and outputs. See Appendix C for a complete overview of all LED indicators.
Lithium battery protection
Excessive input voltage and transients are regulated down to a safe level.
The Smart BMS will stop charging in case of cell over voltage or over temperature.
It has three outputs, similar to the smallBMS:
Load disconnect
Can be used to control the remote on/off input of a BatteryProtect, inverter, DC-DC converter or other loads that have remote on/off port functionality.
Normally the Load disconnect output is high and becomes free-floating when cell undervoltage is imminent (default 2.8V, adjustable in battery). Maximum current: 10mA
Pre-alarm
The pre-alarm output can be used to issue a visible or audible warning when the battery voltage is low and will trip with a minimum delay of 30 seconds before the Load disconnect output is disabled due to cell undervoltage.
The output may be used to drive a relay, LED or Buzzer and can be configured as continuous or intermittent signal.
Its output is normally free floating and becomes high in case of imminent cell undervoltage (default 3,1V, adjustable in battery). Maximum current: 1A (not short circuit protected).
Charge disconnect
The Charge disconnect output can be used to control the remote on/off port of a charger, such as the Phoenix Smart Charger IP43, a Cyrix-Li-Charge relay, a Cyrix-Li-ct Battery Combiner or a BatteryProtect. Note that the Charge disconnect output is not suitable to power an inductive load such as a relay coil.
The output is normally high and becomes free floating in case of imminent cell overvoltage or overtemperature. Maximum current: 10mA
Note
In some cases an interface cable such as a non-inverting or inverting on/off cable may be required, see Appendix A.
Setup, configuration and monitoring via VictronConnect
Initial setup, configuration, monitoring and diagnostics of the BMS is done via Bluetooth and the VictronConnect app.
This includes Instant Readout; a way to view key BMS parameters in real time without having to pair with the BMS.
The advantage is:
Better range than a regular Bluetooth connection
The key data at a glance
Encrypted data
Visual notifications of warnings, alarms and errors
This feature is available for a large number of other Victron smart products
2.3. What's in the box
Smart BMS 12-200
Ground wire with 10mm eye terminal
2-pin plug with pre-installed wire loop
3-pin plug for load/charge disconnect and pre-alarm
Megafuse 200A pre-installed
ATO fuse holder with 2x 7.5A fuse