1. Specifications

The following specifications must be met to ensure a safe and optimal work with the foxBMS hardware.

1.1. BMS-Master

1.1.1. Electrical Ratings

Description Minimum Typical Maximum Unit
Supply Voltage DC 10 26 V
Contactor Continuous Current 4 A
Contactor Feedback Supply Voltage 5.0 V
Analog Input 3.3 V
Isolated Contacts Continuous Current 4 A
Interlock Circuit Sink Current 10 mA
Idle Supply Current at 12V supply 150 mA
Idle Supply Current at 24V supply 110 mA

1.1.2. Mechanical Dimensions (BMS-Master PCB only)

Description Value Unit
Width 120 mm
Length 160 mm
Height 15 mm
Weight 122 g

1.1.3. Mechanical Dimensions (BMS-Master Unit in housing)

The BMS-Master Unit consists of BMS-Master board, BMS-Interface board and BMS-Extension board and is mounted in an aluminum housing.

Description Value Unit
Width 124 mm
Length 164 mm
Height 49.2 mm
Weight 785 g

1.2. BMS-Slave 12-Cell

1.2.1. Electrical Ratings

The current consumption from the module has been measured at 43.2V module voltage, which is equivalent to a cell-voltage of 3.6V per cell. No sense lines have been connected from this measurment (as the impact of cell voltage sensing is neglectable on the current consumption).

The DC supply current has been measured with a voltage of 12V and no Vbat or cells connected.

Description Minimum Typical Maximum Unit
Battery Module Voltage 11 60 V
Single Battery Cell Voltage 0 5 V
Temperature Sensor Inputs 10k Ω
Analog Inputs (pin headers) 0 5 V
Digital Inputs/Outputs (pin headers) 0 5 V
External DC Supply (HW version 2.1.0 and above) 8 12 24 V
Current consumption: Primary in sleep, Secondary in sleep 9.1µ A
Current consumption: Primary active, Secondary in sleep 11.64m A
Current consumption: Primary active, Secondary active 22.33m A
DC supply current: Primary in sleep, Secondary in sleep 4.3m A
DC supply current: Primary active, Secondary in sleep 73.6m A
DC supply current: Primary active, Secondary active 144.3m A

1.2.2. Mechanical Dimensions (PCB only)

Description Value Unit
Width 100 mm
Length 160 mm
Height 15 mm
Weight 83 g

1.3. BMS-Slave 18-Cell

1.3.1. Electrical Ratings

The current consumption from the module has been measured at 64.8V module voltage, which is equivalent to a cell-voltage of 3.6V per cell. No sense lines have been connected from this measurment (as the impact of cell voltage sensing is neglectable on the current consumption).

The DC supply current has been measured with a voltage of 12V and no Vbat or cells connected.

Description Minimum Typical Maximum Unit
Battery Module Voltage 16 90 V
Single Battery Cell Voltage 0 5 V
Temperature Sensor Inputs 10k Ω
Analog Inputs (pin headers) 0 5 V
Digital Inputs/Outputs (pin headers) 0 5 V
External DC Supply 8 12 24 V
Current consumption: Primary in sleep, Secondary in sleep 13.35µ A
Current consumption: Primary active, Secondary in sleep 11.66m A
Current consumption: Primary active, Secondary active 22.35m A
DC supply current: Primary in sleep, Secondary in sleep 3.3m A
DC supply current: Primary active, Secondary in sleep 112.0m A
DC supply current: Primary active, Secondary active 211.6m A

1.3.2. Mechanical Dimensions (PCB only)

Description Value Unit
Width 100 mm
Length 160 mm
Height 15 mm
Weight 88 g