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BMU dashboard

The Battery Management Unit (BMU) dashboard shows the data of a Prohelion Battery Management System (BMS). It appears as a tab in the sidebar once a Prohelion BMU is added to the Profile.

Prohelion BMU dashboard showing the summary row, cell graphs, status indicators and state flowchart

Prohelion BMU

The top section of the dashboard shows data from the BMU. Select the MORE DETAILS banner to expand it and display telemetry from the Cell Management Units (CMUs). The controls for the CAN signals and messages on the dashboard open the CAN signals and messages from the BMS in the CAN database (DBC) viewer.

BMU data

The top row summarises these values:

  • The battery voltage.
  • The current, which is negative when it flows into the battery.
  • The state of charge (SOC) as a percentage of the user-set pack capacity (SOC %).
  • The maximum and minimum cell voltage in the pack.
  • The maximum and minimum cell temperature in the pack.

The summary row is followed by graphs of the cell temperatures and node voltages that the CMUs observe. Hover over a graph to see the data in greater resolution.

The status indicators show battery events. The indicators depend on the BMS in use and include:

  • Cell over voltage and under voltage.
  • Cell over temperature.
  • Untrusted measurements.
  • CMU and vehicle timeouts.
  • An invalid SOC estimation.

The D1000 Gen2 dashboard instead shows the reasons reported by the BMS, including a separate PRECHARGE FAIL REASON group for a failed precharge. In that group, HVIL means the High-Voltage Interlock Loop is measuring a high impedance, which points to a connector failure. BJU means the Battery Junction Unit (BJU) has not responded to requests for measurements.

A flowchart shows the progression of the BMU state machine, with the current state in the grey box. The states depend on the model and firmware. The dashboard extends the D1000 Gen1 state machine with a Discovery state. The table of models links the reference pages for each model.

Model Status flags State machine Configuration parameters
D1000 Gen1 Transmitted CAN Packets BMS State Machine Not listed separately
D1000 Gen2, Firmware V1.2 Messages and Signals (BMS Info message) State Machine Configuration Parameters
D1000 Gen2, Firmware V1.1 Messages and Signals (BMS Info message) State Machine Configuration Parameters
M48 Gen1 Not listed separately Software Specifications Software Specifications

Node telemetry

The Node Telemetry table lists the connected CMUs and the voltage of each cell they monitor. The columns depend on the BMS model. For a D1000 Gen1 they are:

  • The CMU serial number (Node Number).
  • The CMU board and external cell temperatures (PCB C and Cell C).
  • The voltage of each cell in millivolts (Cell 1 - 8 mV). A negative voltage is a trust error, where the two redundant measurement channels disagree, and the table shows it without the minus sign. The value -32768 indicates a cell position that the BMU has not configured as present, as described in Transmitted CAN Packets.

Node Telemetry table listing each CMU and the voltage of each cell it monitors

Prohelion CMU

The colour of each voltage reading shows additional information, and every cell shows its voltage in millivolts as text, except where the colour table says otherwise. Without a loaded firmware configuration, the balancing, zero state of charge, and critical thresholds are not applied.

Colour Meaning Text in the cell
Gold The highest voltage cell. The voltage
Light salmon The lowest voltage cell. The voltage
Pale blue The cell is balancing, at or above the cell balancing voltage in the firmware configuration. The voltage
Pale yellow The cell is at or below the voltage that corresponds to zero state of charge, or is not present. The voltage, or no text when the cell is not present
Red The voltage is at or beyond the critical under-voltage or over-voltage threshold. The voltage
Grey The reading is outside the range the table displays. No text
Yellow-green gradient A cell with none of the conditions above. The voltage

To change the BMU configuration or flash its firmware, refer to Update BMU configuration and firmware.