# Parameters of the BMS

This page will describe the variables of the BMS. \
There are 6 kind of parameters

1. The common battery variables
2. The calculated battery variables
3. The additional battery variables
4. The configuration variables 
5. The CAN variables
6. The hardware parameters 

{% hint style="info" %}
In the console (CLI) type "bms get all" to get all the parameters and its current value.

In the console (CLI) type: "bms help parameters" to get more info on the parameters.
{% endhint %}

##  The BMS parameter lists

### The common battery variables list <a href="#ref167459253" id="ref167459253"></a>

Table 1.       Common battery variables list

<table data-header-hidden><thead><tr><th width="127"></th><th width="68"></th><th width="105"></th><th width="231"></th><th width="91"></th><th width="70"></th><th></th></tr></thead><tbody><tr><td>Parameter</td><td>Unit</td><td>Datatype</td><td>Description</td><td>Default</td><td>RO/RW</td><td>No</td></tr><tr><td>v-out</td><td>V</td><td>float</td><td>The voltage of the BMS output</td><td>0</td><td>RO</td><td>0</td></tr><tr><td>v-batt</td><td>V</td><td>float</td><td>The voltage of the battery pack</td><td>0</td><td>RO</td><td>1</td></tr><tr><td>n-cells</td><td>-</td><td>uint8_t</td><td>Number of cells used in the BMS board</td><td>3</td><td>RW</td><td>2</td></tr><tr><td>v-cell1</td><td>V</td><td>float</td><td>The voltage of cell 1</td><td>0</td><td>RO</td><td>3</td></tr><tr><td>v-cell2</td><td>V</td><td>float</td><td>The voltage of cell 2</td><td>0</td><td>RO</td><td>4</td></tr><tr><td>v-cell3</td><td>V</td><td>float</td><td>The voltage of cell 3</td><td>0</td><td>RO</td><td>5</td></tr><tr><td>v-cell4</td><td>V</td><td>float</td><td>The voltage of cell 4</td><td>0</td><td>RO</td><td>6</td></tr><tr><td>v-cell5</td><td>V</td><td>float</td><td>The voltage of cell 5</td><td>0</td><td>RO</td><td>7</td></tr><tr><td>v-cell6</td><td>V</td><td>float</td><td>The voltage of cell 6</td><td>0</td><td>RO</td><td>8</td></tr><tr><td>i-batt</td><td>A</td><td>float</td><td>The last recorded current of the battery</td><td>0</td><td>RO</td><td>9</td></tr><tr><td>i-batt-avg</td><td>A</td><td>float</td><td><p>The average current since the last</p><p>measurement (period t-meas (default 1s))</p></td><td>0</td><td>RO</td><td>10</td></tr><tr><td>i-batt-10s-avg</td><td>A</td><td>float</td><td><p>The 10s rolling average current, updated</p><p>each t-meas, default 1000 (ms)</p></td><td>0</td><td>RO</td><td>11</td></tr><tr><td>sensor-enable</td><td>-</td><td>bool</td><td><p>This variable is used to enable or disable</p><p>the battery temperature sensor, 0 is</p><p>disabled, 1 is enabled</p></td><td>0</td><td>RW</td><td>12</td></tr><tr><td>c-batt</td><td>C</td><td>float</td><td><p>The temperature of the external battery</p><p>temperature sensor</p></td><td>0</td><td>RO</td><td>13</td></tr><tr><td>c-afe</td><td>C</td><td>float</td><td>The temperature of the analog front end</td><td>0</td><td>RO</td><td>14</td></tr><tr><td>c-t</td><td>C</td><td>float</td><td>The temperature of the transistor (switch)</td><td>0</td><td>RO</td><td>15</td></tr><tr><td>c-r</td><td>C</td><td>float</td><td>The temperature of the sense resistor</td><td>0</td><td>RO</td><td>16</td></tr></tbody></table>

&#x20;

&#x20;

### The calculated battery variables list

Table 2.       Calculated battery variables list

<table data-header-hidden><thead><tr><th width="126"></th><th width="67"></th><th width="106"></th><th width="258"></th><th width="90"></th><th width="66"></th><th></th></tr></thead><tbody><tr><td>Parameter</td><td>Unit</td><td>Datatype</td><td>Description</td><td>Default</td><td>RO/RW</td><td>No</td></tr><tr><td>p-avg</td><td>W</td><td>float</td><td><p>Average power consumption over the</p><p>last 10 seconds.</p></td><td>0</td><td>RO</td><td>17</td></tr><tr><td>e-used</td><td>Wh</td><td>float</td><td>Power consumption since device boot</td><td>0</td><td>RO</td><td>18</td></tr><tr><td>t-full</td><td>h</td><td>float</td><td><p>Charging is expected to complete in this</p><p>time; zero if not charging.</p></td><td>0</td><td>RO</td><td>19</td></tr><tr><td>a-rem</td><td>Ah</td><td>float</td><td>Remaining capacity in the battery</td><td>0</td><td>RW</td><td>20</td></tr><tr><td>a-full</td><td>Ah</td><td>float</td><td><p>Full charge capacity, predicted battery</p><p>capacity when it is fully charged.</p><p>Decreases with aging.</p></td><td>4.6</td><td>RW</td><td>21</td></tr><tr><td>a-factory</td><td>Ah</td><td>float</td><td>Battery capacity stated by the factory</td><td>4.6</td><td>RW</td><td>22</td></tr><tr><td>s-charge</td><td>%</td><td>uint8_t</td><td>Percentage of the full charge 0 - 100%.</td><td>0</td><td>RO</td><td>23</td></tr><tr><td>s-health</td><td>%</td><td>uint8_t</td><td><p>Health of the battery in percentage, use</p><p>STATE_OF_HEALTH_UNKNOWN =</p><p>127 if cannot be estimated.</p></td><td>127</td><td>RO</td><td>24</td></tr><tr><td>s-out</td><td>-</td><td>bool</td><td>This is true if the output power is enabled.</td><td>0</td><td>RO</td><td>25</td></tr><tr><td>s-in-flight</td><td>-</td><td>bool</td><td><p>This is true if the system is in flight (with</p><p>flight-mode-enable and i-flight-mode)</p></td><td>0</td><td>RO</td><td>26</td></tr><tr><td>batt-id</td><td>-</td><td>uint8_t</td><td><p>Identifies the battery within this vehicle,</p><p>0 - primary battery.</p></td><td>0</td><td>RW</td><td>27</td></tr></tbody></table>

### The additional battery variables list <a href="#ref167459217" id="ref167459217"></a>

Table 3.       Additional battery variables list

<table data-header-hidden><thead><tr><th width="128"></th><th width="67"></th><th width="105"></th><th width="242"></th><th width="92"></th><th width="66"></th><th></th></tr></thead><tbody><tr><td>Parameter</td><td>Unit</td><td>Datatype</td><td>Description</td><td>Default</td><td>RO/RW</td><td>No</td></tr><tr><td>v-cell-ov</td><td>V</td><td>float</td><td>Battery maximum allowed voltage for one cell. exceeding this voltage, the BMS will go to fault mode</td><td>4.2</td><td>RW</td><td>28</td></tr><tr><td>v-cell-uv</td><td>V</td><td>float</td><td><p>Battery minimum allowed voltage for one cell.</p><p>Going below this voltage, the BMS will go to</p><p>fault mode followed by deepsleep after</p><p>t-fault-timeout</p></td><td>3</td><td>RW</td><td>29</td></tr><tr><td>v-cell-nominal</td><td>V</td><td>float</td><td>Battery nominal voltage for one cell. will be used for energy calculation.</td><td>3.7</td><td>RW</td><td>30</td></tr><tr><td>v-storage</td><td>V</td><td>float</td><td>The voltage what is specified as storage voltage for a cell</td><td>3.8</td><td>RW</td><td>31</td></tr><tr><td>v-cell-margin</td><td>mV</td><td>uint8_t</td><td>Cell voltage charge margin to decide or not to go through another topping charge cycle</td><td>50</td><td>RW</td><td>32</td></tr><tr><td>v-recharge-margin</td><td>mV</td><td>Uint16_t</td><td>Cell voltage charge complete margin to decide or not to do a battery re-charge, to keep the cell voltages at max this much difference with the cell-ov</td><td>200</td><td>RW</td><td>33</td></tr><tr><td>i-peak-max</td><td>A</td><td>float</td><td>Maximum peak current threshold to open the switch during normal operation, can't be overruled</td><td>200</td><td>RW</td><td>34</td></tr><tr><td>i-out-max</td><td>A</td><td>float</td><td>Maximum current threshold to open the switch during normal operation, if not overruled</td><td>60</td><td>RW</td><td>35</td></tr><tr><td>i-out-nominal</td><td>A</td><td>float</td><td>Nominal discharge current (informative only)</td><td>60</td><td>RW</td><td>36</td></tr><tr><td>i-flight-mode</td><td>A</td><td>uint8_t</td><td>Current threshold to not disable the power in flight mode</td><td>5</td><td>RW</td><td>37</td></tr><tr><td>i-sleep-oc</td><td>mA</td><td>uint8_t</td><td>Overcurrent threshold detection in sleep mode that will wake up the BMS and also the threshold to detect the battery is not in use</td><td>30</td><td>RW</td><td>38</td></tr><tr><td>i-system</td><td>mA</td><td>uint8_t</td><td><p>Current of the BMS board itself, this is</p><p>measured (as well) during charging, so</p><p>this needs to be subtracted</p></td><td>40</td><td>RW</td><td>39</td></tr><tr><td>i-charge-max</td><td>A</td><td>float</td><td><p>Maximum current threshold to open the</p><p>switch during charging</p></td><td>4.6</td><td>RW</td><td>40</td></tr><tr><td>i-charge-nominal</td><td>A</td><td>float</td><td><p>Nominal charge current (informative</p><p>only)</p></td><td>4.6</td><td>RW</td><td>41</td></tr><tr><td>i-charge-full</td><td>mA</td><td>uint16_t</td><td><p>Current threshold to detect end of charge</p><p>sequence</p></td><td>50</td><td>RW</td><td>42</td></tr><tr><td>c-cell-ot</td><td>C</td><td>float</td><td><p>Over temperature threshold for the cells.</p><p>Going over this threshold and the BMS</p><p>will go to FAULT mode</p></td><td>45</td><td>RW</td><td>43</td></tr><tr><td>c-cell-ut</td><td>C</td><td>float</td><td><p>Under temperature threshold for the cells.</p><p>Going under this threshold and the BMS will</p><p>go to FAULT mode</p></td><td>-20</td><td>RW</td><td>44</td></tr><tr><td>c-pcb-ot</td><td>C</td><td>float</td><td><p>PCB Ambient temperature over temperature</p><p>threshold</p></td><td>45</td><td>RW</td><td>45</td></tr><tr><td>c-pcb-ut</td><td>C</td><td>float</td><td><p>PCB Ambient temperature under Temperature</p><p>threshold</p></td><td>-20</td><td>RW</td><td>46</td></tr><tr><td>c-cell-ot-charge</td><td>C</td><td>float</td><td><p>Over temperature threshold for the cells</p><p>During charging. Going over this threshold and</p><p>the BMS will go to FAULT mode.</p><p> </p><p> </p></td><td>40</td><td>RW</td><td>47</td></tr><tr><td>c-cell-ut-charge</td><td>C</td><td>float</td><td><p>Under temperature threshold for the cells</p><p>during charging. Going under this</p><p>threshold during charging and the BMS</p><p>will go to FAULT mode</p></td><td>0</td><td>RW</td><td>48</td></tr><tr><td>n-charges</td><td>-</td><td>uint16_t</td><td>The number of charges done</td><td>0</td><td>RW</td><td>49</td></tr><tr><td>n-charges-full</td><td>-</td><td>uint16_t</td><td>The number of complete charges</td><td>0</td><td>RW</td><td>50</td></tr><tr><td>ocv-slope</td><td>mV/A.min</td><td>float</td><td><p>The slope of the OCV curve. This will</p><p>be used to calculate the balance time. </p></td><td>5.3</td><td>RW</td><td>51</td></tr><tr><td>battery-type</td><td>-</td><td>uint8_t</td><td><p>The type of battery attached to it.</p><p>0 = LiPo, 1 = LiFePO4, 2 = LiFeYPO4,</p><p>3 = NMC (LiPo type, LiNiMnCoO2),</p><p>4 = Na-ion (Sodium-ion, SIB). Could be</p><p>extended. Will change OV, UV, v-storage,</p><p>OCV/SoC table if changed runtime.</p></td><td>3</td><td>RW</td><td>52</td></tr></tbody></table>

### &#x20;The configuration variables list <a href="#ref167459195" id="ref167459195"></a>

Table 4.       Configuration variables list

&#x20;

<table data-header-hidden><thead><tr><th width="132"></th><th width="68"></th><th width="104"></th><th width="231"></th><th width="106"></th><th width="65"></th><th></th></tr></thead><tbody><tr><td>Parameter</td><td>Unit</td><td>Datatype</td><td>Description</td><td>Default</td><td>RO/RW</td><td>No</td></tr><tr><td>t-meas</td><td>ms</td><td>uint16_t</td><td>Cycle of the battery to perform a complete battery measurement and SOC estimation can only be 10000 or a whole division of 10000 (For example: 5000, 1000, 500)</td><td>1000</td><td>RW</td><td>53</td></tr><tr><td><del>t-ftti</del></td><td><del>ms</del></td><td><del>uint16_t</del></td><td><del>Cycle of the battery to perform diagnostics (Fault Tolerant Time Interval)</del></td><td><del>1000</del></td><td><del>RW</del></td><td><del>54</del></td></tr><tr><td>t-bms-timeout</td><td>s</td><td>uint16_t</td><td>Timeout for the BMS to go to SLEEP mode when the battery is not used.</td><td>600</td><td>RW</td><td>55</td></tr><tr><td>t-fault-timeout</td><td>s</td><td>uint16_t</td><td>After this timeout, with an undervoltage fault the battery will go to DEEPSLEEP mode to preserve power. 0 sec is disabled.</td><td>60</td><td>RW</td><td>56</td></tr><tr><td>t-bcc-sleep-cyclic</td><td>s</td><td>uint8_t</td><td>Wake up cyclic timing of the AFE (after front end) during sleep mode</td><td>1</td><td>RW</td><td>57</td></tr><tr><td>t-sleep-timeout</td><td>h</td><td>uint8_t</td><td>When the BMS is in sleep mode for this period it will go to the self-discharge mode, 0 if disabled.</td><td>24</td><td>RW</td><td>58</td></tr><tr><td>t-ocv-cyclic0</td><td>s</td><td>int32_t</td><td>OCV measurement cyclic timer start (timer is increase by 50% at each cycle)</td><td>300</td><td>RW</td><td>59</td></tr><tr><td>t-ocv-cyclic1</td><td>s</td><td>int32_t</td><td>OCV measurement cyclic timer final value (limit)</td><td>86400</td><td>RW</td><td>60</td></tr><tr><td>t-charge-detect</td><td>s</td><td>uint8_t</td><td>During NORMAL mode, if the battery current is positive for more than this time, then the BMS will go to CHARGE mode</td><td>1</td><td>RW</td><td>61</td></tr><tr><td>t-cb-delay</td><td>s</td><td>uint8_t</td><td>Time for the cell balancing function to start after entering the CHARGE mode</td><td>120</td><td>RW</td><td>62</td></tr><tr><td>t-charge-relax</td><td>s</td><td>uint16_t</td><td>Relaxation time after the charge is complete before going to another charge round.</td><td>300</td><td>RW</td><td>63</td></tr><tr><td>batt-eol</td><td>%</td><td>uint8_t</td><td>Percentage at which the battery is end-of-life and shouldn’t be used anymore Typically between 90%-50%</td><td>80</td><td>RW</td><td>64</td></tr><tr><td>s-flags</td><td>-</td><td>uint8_t</td><td><p>This contains the status flags as</p><p>described in BMS_status_flags_t</p></td><td>255</td><td>RO</td><td>65</td></tr><tr><td>self-discharge-enable</td><td>-</td><td>bool</td><td>This variable is used to enable or disable the SELF_DISCHARGE state, 0 is disabled, 1 is enabled</td><td>1</td><td>RW</td><td>66</td></tr><tr><td>flight-mode-enable</td><td>-</td><td>bool</td><td>This variable is used to enable or disable flight mode, is used together with i-flight-mode. 0 is disabled</td><td>0</td><td>RW</td><td>67</td></tr><tr><td>emergency-button-enable</td><td>-</td><td>bool</td><td>This variable is used to enable or disable the emergency button on PTE8.</td><td>0</td><td>RW</td><td>68</td></tr><tr><td>smbus-enable</td><td>-</td><td>bool</td><td>This variable is used to enable or disable the SMBus update.</td><td>0</td><td>RW</td><td>69</td></tr><tr><td>gate-check-enable</td><td>-</td><td>bool</td><td>This variable is used to enable or disable the gate safety check. If true, it will check if it can be turned off, based on output voltage.</td><td>1</td><td>RW</td><td>70</td></tr><tr><td>model-id</td><td>-</td><td>uint64_t</td><td>Model id, set to 0 if not applicable</td><td>0</td><td>RW</td><td>71</td></tr><tr><td>model-name</td><td>-</td><td>char[32]</td><td><p>Battery model name, model name is a</p><p>human-readable string that could</p><p>include the vendor, model, chemistry.</p></td><td>"BMS772"</td><td>RW</td><td>72</td></tr></tbody></table>

### The can variables list <a href="#ref167459188" id="ref167459188"></a>

Table 5.       Can variables list

<table data-header-hidden><thead><tr><th width="131"></th><th width="73"></th><th width="107"></th><th width="222"></th><th width="110"></th><th width="69"></th><th></th></tr></thead><tbody><tr><td>Parameter</td><td>Unit</td><td>Datatype</td><td>Description</td><td>Default</td><td>RO/RW</td><td>No</td></tr><tr><td>cyphal-node-static-id*</td><td>-</td><td>uint8_t</td><td>This is the node ID of the CYPHAL node. Should be between 1 - 127 or 255 for PNP.</td><td>255</td><td>RW</td><td>73</td></tr><tr><td>cyphal-es-sub-id*</td><td>-</td><td>uint16_t</td><td>This is the subject ID of the energy source CYPHAL message (1...100Hz)</td><td>4096</td><td>RW</td><td>74</td></tr><tr><td>cyphal-bs-sub-id*</td><td>-</td><td>uint16_t</td><td>This is the subject ID of the battery status CYPHAL message (1Hz)</td><td>4097</td><td>RW</td><td>75</td></tr><tr><td>cyphal-bp-sub-id*</td><td>-</td><td>uint16_t</td><td>This is the subject ID of the battery parameters CYPHAL message (0.2Hz)</td><td>4098</td><td>RW</td><td>76</td></tr><tr><td>cyphal-legacy-bi-sub-id*</td><td>-</td><td>uint16_t</td><td>This is the subject ID of the battery info legacy CYPHAL message (0.2 ~ 1Hz)</td><td>65535</td><td>RW</td><td>77</td></tr><tr><td>dronecan-node-static-id</td><td>-</td><td>uint8_t</td><td>This is the node ID of the DRONECAN node. Should be between 1 - 127 or 255 for dynamic node id.</td><td>0</td><td>RW</td><td>78</td></tr><tr><td>dronecan-bat-continuous</td><td>-</td><td>uint8_t</td><td>This indicates if the particular DroneCAN topic has to be published</td><td>0</td><td>RW</td><td>79</td></tr><tr><td>dronecan-bat-periodic</td><td>-</td><td>uint8_t</td><td>This indicates if the particular DroneCAN topic has to be published</td><td>0</td><td>RW</td><td>80</td></tr><tr><td>dronecan-bat-cells</td><td>-</td><td>uint8_t</td><td>This indicates if the particular DroneCAN topic has to be published</td><td>0</td><td>RW</td><td>81</td></tr><tr><td>dronecan-bat-info</td><td>-</td><td>uint8_t</td><td>This indicates if the particular DroneCAN topic has to be published</td><td>1</td><td>RW</td><td>82</td></tr><tr><td>dronecan-bat-info-aux</td><td>-</td><td>uint8_t</td><td>This indicates if the particular DroneCAN topic has to be published</td><td>1</td><td>RW</td><td>83</td></tr><tr><td>can-mode</td><td>-</td><td>char[32]</td><td>Options “OFF”, "DRONECAN" and "CYPHAL". To indicate which is used.</td><td>“OFF”</td><td>RW</td><td>84</td></tr><tr><td>can-fd-mode*</td><td>-</td><td>uint8_t</td><td>If true CANFD is used, otherwise classic CAN is used</td><td>0</td><td>RW</td><td>85</td></tr><tr><td>can-bitrate*</td><td>bit/s</td><td>int32_t</td><td>The bitrate of classical can or CAN FD arbitration bitrate</td><td>1000000</td><td>RW</td><td>86</td></tr><tr><td>can-fd-bitrate*</td><td>bit/s</td><td>int32_t</td><td>The bitrate of CAN FD data bitrate</td><td>4000000</td><td>RW</td><td>87</td></tr></tbody></table>

A ~~line~~ means this is not implemented yet.

\* These parameters will only be implemented during startup of the BMS

&#x20;

### The hardware parameters

Table 6.       BMS hardware parameters list

<table data-header-hidden><thead><tr><th width="128"></th><th width="69"></th><th width="103"></th><th width="261"></th><th width="89"></th><th width="65"></th><th></th></tr></thead><tbody><tr><td>Parameter</td><td>Unit</td><td>Datatype</td><td>Description</td><td>Default</td><td>RO/RW</td><td>No</td></tr><tr><td>v-min</td><td>V</td><td>uint8_t</td><td>Minimum stack voltage for the BMS board to be fully functional</td><td>6</td><td>RW</td><td>88</td></tr><tr><td>v-max</td><td>V</td><td>uint8_t</td><td>Maximum stack voltage allowed by the BMS board</td><td>26</td><td>RW</td><td>89</td></tr><tr><td>i-range-max</td><td>A</td><td>uint16_t</td><td>Maximum current that can be measured by the BMS board</td><td>300</td><td>RW</td><td>90</td></tr><tr><td>i-max</td><td>A</td><td>uint8_t</td><td>Maximum DC current allowed in the BMS board (limited by power dissipation in the MOSFETs). For info only. Use i-out-max for a limit.</td><td>60</td><td>RW</td><td>91</td></tr><tr><td>i-short</td><td>A</td><td>uint16_t</td><td>Short circuit current threshold (typical: 550A, min: 500A, max: 600A)</td><td>500</td><td>RW</td><td>92</td></tr><tr><td>t-short</td><td>us</td><td>uint8_t</td><td>Blanking time for the short circuit detection</td><td>20</td><td>RW</td><td>93</td></tr><tr><td>i-bal</td><td>mA</td><td>uint8_t</td><td>Cell balancing current under 4.2V with cell balancing resistors of 82 ohms</td><td>50</td><td>RW</td><td>94</td></tr><tr><td>m-mass</td><td>kg</td><td>float</td><td>The total mass of the (smart) battery</td><td>0</td><td>RW</td><td>95</td></tr><tr><td>f-v-out-divider-factor</td><td>-</td><td>float</td><td>The factor of the output voltage divider as component tolerances could be different to not result in 11.0.</td><td>11.0</td><td>RW</td><td>96</td></tr></tbody></table>

A ~~line~~ means this is not implemented yet.


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