Configuration

Inputs and outputs

​​​​​​Discrete inputs

The BMS Main 3 device has 6 discrete inputs that detect signal line closing to the virtual ground, and 2 inputs that detect 9-32V input voltage. For each discrete input, its assignment and inversion flag are set.

Also, BMS has two additional configurable inputs named “KEYRUN” and “CHARGE_ON”, each serves 9-32V input voltage. Those inputs serve as power buttons with additional functions that can be set.

Assignments of discrete inputs are configured in the "Signals → Input discrete signals → Assignments" section:

Inversion flags for discrete inputs are configured in the "Signals → Input discrete signals → Inversion" section:

The behavior of “KEYRUN” signal can be configured in the "Signals → Input discrete signals → KEYRUN mode" section:

The behavior of “CHARGE_ON” signal can be configured in the "Signals → Input discrete signals → CHARGE_ON mode" section:

In both “KEYRUN mode” and “CHARGE_ON mode“ sections:

• Do nothing – power on device and do nothing;
• Set “Discharge request” – power on device and set “Discharge request” signal immediately;
• Set “Charge request” – power on device and set “Charge request” signal immediately.

Current sensor

The BMS Main 3 device has an ability to measure battery current by 3 external Hall-Effect current sensors.

Current sensor settings are configured in the "Signals → Current sensor" section:

The device supports the following current sensor settings:

• Connection – type of multiple sensors connection
  • One sensor (#1) – only first sensor is used to measure the battery current;
  • Two sensors (#1 and #2) in parallel – sensors are connected in parallel (the total battery current equals the sum of two sensors);
  • Two sensors (#1 and #2) in different branches – sensors located in two halves of the battery (used in batteries with a middle point);
• Sensor 2, 3: Enable – a flag to enable the second of third current sensor;
• Sensor 1, 2, 3: Nominal current – rated current I_nom of the sensor according to the datasheet, А;
• Sensor 1, 2, 3: Sensitivity – sensitivity of the current sensor according to the datasheet, V / I_nom.;
• Sensor 1, 2, 3: Invert – invert the sign of the measured value;
• Sensor 1, 2, 3: Multiply charging current (experimental) – an experimental flag for scaling the charging current by given multiplier;
• Sensor 1, 2, 3: Multiplier for charging current – charging current multiplier;
• Sensor 1, 2, 3: REF_IN2 mode – mode of additional analog line:
  • Not connected;
  • Reference line – reference output of the sensor;
  • Low range (for the dual range sensor) - a second output of a dual-range sensor (for example, LEM DHAB series);
• Sensor 1, 2, 3: Low range nominal current - rated current I_nom of the low current line of dual range sensor according to the datasheet, А;
• Sensor 1, 2, 3: Low range sensitivity – sensitivity of the low current line of dual range sensor according to the datasheet, V / I_nominal.;
• Sensor 1, 2, 3: Threshold for low range – a threshold current value at which the device uses the readings of the high current sensor instead of low current, A;
• Calibrate – a flag to calibrate (find a 0A point) the current sensor when the device is started;
• Calibration time – calibration time of the current sensor, millisecond;
• Recalibrate current sensor – a command to calibrate the current sensor manually.

Shunt sensor (CAN bus)

The BMS Main 3 device has an ability to measure battery current via a shunt sensor, connected to the CAN bus.

Shunt sensor settings are configured in the "Signals → Shunt sensor (CAN bus)" section:

The device supports the following shunt sensor settings:

• Enable – a flag to start interaction with the BMS Current Sensor (if interaction is enabled, then BMS doesn’t use Hall-Effect current sensor which settings are described in the section "Signals → Current sensor");
• Node ID – an address of BMS Current Sensor in the CANopen network;
• Invert – a flag to invert current measurements;
• Receive timeout – a timeout for receiving messages from the BMS Current Sensor (if no data is being received from the current sensor during this time, the “Shunt offline” flag is set), millisecond;
• Mean value threshold – T_M level, A (if module of instantaneous current (I_I) which is received from the shunt sensor is between T_M and T₀, the BMS will use mean value of current I_M; if I_I is greater than T_M, the BMS will use instantaneous value of current I_I);
• Zero threshold – T₀ level, A (if module of instantaneous current (I_I) which is received from the shunt sensor is lower than T₀, the BMS will assume that current flowing through the battery is zero);

Temperature sensors

Temperature sensors settings are configured in the "Signals → Temperature sensors" section:

In this section:

• Type of cell temperature sensors – a type of temperature sensors connected to BMS Logic devices and used to measure cells temperature;
• Unused cell temperature sensors – a bitfield to select unused temperature sensors on each BMS Logic;
• Type of temperature sensors 1 and 2 – a type of temperature sensors connected to BMS Main 3.

Output discrete signals

The BMS Main 3 device has 4 open drain type outputs. For each discrete output, its assignment and inversion flag are set.

Assignments of discrete outputs are configured in the "Signals → Output discrete signals → Assignments" section:

Inversion flags for discrete outputs are configured in the "Signals → Output discrete signals → Inversion" section:

Power switches

The BMS Main 3 device has 6 power switches to drive contactors. For each switch, its assignment and inversion flag are set.

Assignments of power switches are configured in the "Signals → Power switches → Assignments" section:

Inversion flags for switches are configured in the “Signals → Power switches → Inversion” section: