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Component Description For Battery Management System Control Unit - GF54.10-P-3012KJE

MODEL 453.091/391/491 with ENGINE 780 

Fig 1: Battery Management System Control Unit Component Location - Engine 780
G12093883Courtesy of MERCEDES-BENZ USA

Location 

The battery management system control unit (N82/2) is in the high-voltage battery.

The high-voltage battery is located below the passenger compartment.

IMPORTANT The battery management system control unit and the high-voltage battery form a unit and cannot be replaced separately.

Task 

IMPORTANT Interlock circuit

The interlock circuit is used as contact protection to protect people against inadvertent contact with high-voltage components. The interlock is an anticipatory contact which opens a little before the high-voltage connections when opening a high-voltage connection. In this way timely discharging of the high-voltage intermediate circuit is achieved by the control units of the high-voltage components.

In order to do this, a 12 V/88Hz interlock signal is looped through all components of the high-voltage on-board electrical system that are can be removed or opened. To do this there is an electrical bridge in each removable high-voltage connection which interrupts the interlock circuit during removal of the high-voltage connection.

These tasks are subdivided as follows:

Reading in of sensors and signals 

These input factors are read in via the following connections:

Evaluation of input factors 

The read-in input factors are evaluated by the battery management system control unit.

Actuation of components 

The actuation of the components takes place via the following connections:

Input factors and output factors for the following components are read in or output over direct lines by the battery management system control unit:

Input factors over a direct line Initial parameters over a direct line Supplemental information
High-voltage DC + High-voltage DC + -
High-voltage DC - High-voltage DC - -
High-voltage interlock for high-voltage disconnect device (S8) - -
Circuit 30 - -
Circuit 31 - -
Actuation of battery management system control unit (N82/2k1) relay 1 (precharge) - -
Actuation of battery management system control unit (N82/2k2) relay 2 (phase signal) - -
Actuation of battery management system control unit (N82/2k3) relay 3 (neutral conductor) - -
Input factors over electric drive-CAN Initial parameters over electric drive-CAN Supplemental information
Electric drive control unit (N127) Electric drive control unit (N127) Includes signals from other control units that are connected via electric drive CAN (CAN EL).
Battery management system control unit (N82/2) Battery management system control unit (N82/2)  
DC/DC converter control unit (N83/1) DC/DC converter control unit (N83/1)  
Charging process monitoring control unit (N83/2) Charging process monitoring control unit (N83/2)  
High-voltage battery charger (7 kW charger) control unit (N83/5) High-voltage battery charger (7 kW charger) control unit (N83/5)  

Structure 

The battery management system control unit consists of a metal housing with three plug connectors and an internal control unit.

Voltage supply 

The battery management system control unit is supplied with power from "circuit 30 fused".

  Wiring diagram for battery management control unit   PE54.10-P-2104-97BEA