METHOD AND APPARATUS FOR MEASURING THE ELECTRIC CURRENT OF A BATTERY SYSTEM

An electric current measuring arrangement (1) and a corresponding method for a battery system with a first control unit (10) comprising a first microcontroller (12) and a second control unit (20) with a second microcontroller (22), an amplifier (24, 32) electrically interconnected between the second microcontroller (22) and terminals (T1, T2) of a shunt resistor (26) for current measurement, a node (N1, N2) interconnected between one of the terminals (T1, T2) of the shunt resistor (26) and the amplifier (24, 32) and a communication line (50) communicatively connecting the first control unit (10) and the second control unit (20). The first microcontroller (12) is configured to generate a test pattern signal (60) and transmit the test pattern signal (60) to the second control unit (20) through the communication line (50). The second control unit (20) is configured to transmit the test pattern signal (60) to the node (N1, N2). The second microcontroller (22) is configured to receive a measuring signal (64, 66) in response to the transmitted test pattern signal (60) through the amplifier (24, 32). The first microcontroller (12) is configured to receive the measuring signal through the communication line (50) from the second microcontroller (22), compare the measuring signal (64, 66) with the generated test pattern signal (60) and detect the functionality of the current measurement based on the comparison.