
2. Introduction
2.1. General description
The Smart BMS CL 12-100 is an all-in-one battery management (BMS) system for Victron Lithium Battery 12,8V Smart batteries.
It has been specifically designed for 12V systems with a 12V alternator such as in vehicles and boats and supports up to 5
batteries in parallel (BTVs are simply daisy-chained).
It monitors and protects each individual battery cell within the battery (or battery bank) and will disconnect the alternator, charge
sources or DC loads in case of low/high battery cell voltage, or high temperature.
A dedicated alternator input provides 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. The Charge Current Limiter protects the alternator
against overload.
The BMS is also equipped with a remote on/off terminal to turn the BMS (and the system) off via a remote switch, and a pre-alarm
contact to give a warning signal before the BMS will disconnect the batteries from the system. Configuration and control is done
via Bluetooth and the VictronConnect app.
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 [8]).
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:
1. Protect the lithium battery against excessive charge current (important in case of a low capacity battery).
2. 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).
Remote on/off terminal
• The remote on/off terminal can be used to disable alternator charging 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 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 [15] 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:
Smart BMS CL 12-100
Page 2 Introduction