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English
BP-LFP-1375
4. Functionality of BMS
If the
BMS is in ACTIVE MODE,
all critical parameters of the battery system (such as cell
temperature, voltages, currents, etc.) are monitored cyclically by battery management
system for compliance with the limits and the battery system is shut down in the event of
a fault. Charging and discharging is only possible with an activated battery management
system.
Without communication the
BMS is in SLEEP mode,
the load FET is activated. A moni-
toring of critical parameters is included in larger time intervals. It awakens upon detection
of a current flow or communication.
4.1. Protection functions
The BMS has a large number of parameters for detecting fault conditions – their limits
and validity can be specified in detail. The following is a basic breakdown into
short-term,
reversible and permanent errors:
If a short-term, reversible fault occurs during operation (e.g. overcurrent, overtempera-
ture, etc.), the electronics will switch off briefly and then switch off again when the fault
no longer exists, otherwise the battery will remain deactivated.
If a permanent error occurs during operation (e.g. loss of a cell voltage tap, cell overvol-
tage, cell undervoltage), the battery remains permanently deactivated and can only be
re-enabled by the manufacturer (after troubleshooting, via SM bus or similar).
First level of security - short circuit and overload detection:
The BMS has hardware-based short-circuit and overload detection. Regardless of whether
in SLEEP or ACTIVE MODE, current flow monitoring takes place.
Second level of security - fuse:
An additional short-circuit protection in hardware is provided on the BMS and protects
the battery system in the second level of security.