Overview of Safety Functions

V_String, V_DC_EXT

Plausibility check against V_String voltage

V_DC_EXT

Check of polarity reversal

Bat-Com Slave Count

Comparison of number of detected battery modules and number of parameterized modules (“greater than” semantics)

Battery Current

Check of I_String1

Battery Module

Check of each connected battery module (Bat-Com) with regard to cell voltages, temperatures, temperature imbalance in module, and string/voltage imbalance

Bat-Com Time Out

Check of Bat-Com communication timeout

Precharge

Check of time and voltage difference between V_String and V_DC_EXT during precharging

Contactor

Plausibility check of auxiliary contacts compared to main contactor switching condition

E-Stop

Check of whether E-Stop is active

Parameter valid check

Cyclical redundance check

Firmware valid check

CRC check

CPU diagnostic

Check of timers, ports, and watchdog, etc.

VREF2

CRC check

V_REF_INT

Check of timers, ports, and watchdog, etc.

Fault Hardware Logic

Internal status signal FLT of hardware safety circuit

RAM

Test and check of microcontroller RAM

Watchdog trigger

Internal watchdog check, check of timeout watchdog

Cyclic ADC conversion

Check of values

External Watchdog Trigger

Triggering of hardware safety logic - timeout of hardware safety block = 1000 ms

Temperature and voltage dependent Current Monitoring (I_String1)

Comparison of I_String1 and actual charging and discharging limits