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Sleep:
this state places the electronic devices inside modules (SMU) and BMM in low power
consumption: the contactor is open and there is no possibility to charge and discharge battery.
However, CAN communication is still available with BMM.
Safe:
two kinds of faults can occur: warnings and alarms. At warning level, the battery system
stays in nominal mode and only informs about the fault code. If a fault occurs with an alarm
level, the BMM will open the contactor.
Thus, the battery is isolated from the customer application because it has gone out of the safety
perimeter. The charging and discharging operation are not permitted. However, the BMM
remains operational (powered up and awake).
A
“hardware reset” or a “software reset” implies the BMU going into Nominal mode again
(assuming the fault is no more present). Hardware reset corresponds to ON/OFF/ON of the 24V
power supply that reset the alarm. Software reset corresponds either to client reset by CAN
Open (alarms status are sent to client who can or not reset them) or if the fault condition is no
more present for some kind of alarms.
Transition between modes:
#
States transition
Conditions
1
Off -> Init
BMM is supplied with 24Vdc
2
Init -> Stand-by
Initialization ends successfully
3
Stand-by -> Nominal
Contactor closing demand by EMS (CAN Open request)
4
Any states -> Off
Power supply is switched Off
5
Stand-by -> Sleep
One Cell voltage < 3.35V during 2 hours
6
Safe -> Sleep
One Cell voltage < 3.35V during 2 hours
7
Safe -> Stand-by
Critical fault condition reset occurred
8
Init -> Safe
Failure of BMU PBIT
9
Nominal -> Sleep
One Cell voltage < 3.35V during 2 hours
10
Nominal -> Safe
Critical fault condition appears
11
Stand-by -> Safe
Critical fault condition appears
12
Nominal -> Stand-by
Contactor opening demand by EMS (CAN Open request)
4.6. Precharge
The battery system does not implement a precharge function. If a precharge function is
needed from customer side to charge capacitors, this precharge has to be activated before
closing the battery contactor. Then, the customer has to allow the closing of the battery
contactor within 300 seconds after the start-up of the precharge. Otherwise, the alarm 18
« Main contactor status not expected (closed) » may appear.