> For the complete documentation index, see [llms.txt](https://docs.deltaquad.com/tac/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.deltaquad.com/tac/setup/powering-the-vehicle/checking-the-battery-voltage.md).

# Checking the Battery Voltage

{% hint style="info" %}
The DeltaQuad Evo Battery has a nominal voltage of 22.2 V (3.7 V per cell). When fully charged, it reaches 25.2 V (4.2 V per cell). The battery and individual cell voltages can be measured with a battery checker, as explained below.
{% endhint %}

<figure><img src="/files/wLRDAGgHSXvT8TdRqSqm" alt="" width="563"><figcaption></figcaption></figure>

* The DeltaQuad Evo Battery has a power lead with an XT90 connector. This cable and plug are used to power the DeltaQuad Evo.

{% hint style="warning" %}
The power lead is not used for checking the battery voltage.
{% endhint %}

<figure><img src="/files/BRF3VrA1Ed280k9b48Ji" alt="" width="563"><figcaption></figcaption></figure>

* The smaller cable, called the balance lead, is a multi-pin connector that allows the checker to measure the voltage of each cell.

<figure><img src="/files/6QoN1YuV1vJKEEgMS6Ml" alt="" width="563"><figcaption></figcaption></figure>

* Connect this multi-pin connector to the battery checker.&#x20;

<figure><img src="/files/CJmAiIxtR1bg1vIAPdI0" alt="" width="563"><figcaption></figcaption></figure>

* On the balance lead, the outer wires serve as the pack’s main negative (black wire) and positive (red wire) terminals.

<figure><img src="/files/HTbR0csDL5ofXZ15UfjM" alt="" width="563"><figcaption></figcaption></figure>

<figure><img src="/files/gFkkanNyQ8LmAxNCjRAE" alt="" width="563"><figcaption></figcaption></figure>

* Connect the balance lead as indicated on the battery checker. The checker will be powered by the battery through the balance lead.

<figure><img src="/files/MryEYWcEhcoEB97AqYIj" alt="" width="563"><figcaption></figcaption></figure>

<figure><img src="/files/mg1GiQsnIIWp9eOWW5wM" alt="" width="563"><figcaption></figcaption></figure>

<figure><img src="/files/mPHRN2pw15E77Fpg5cpX" alt="" width="563"><figcaption></figcaption></figure>

<figure><img src="/files/u5iwF1Q83YwYIKCV6Gf4" alt="" width="563"><figcaption></figcaption></figure>

* To get an accurate battery percentage readout, set the battery checker to Li-ion type. Use the middle button to enter the menu, then the arrows to navigate to **Battery Type** and select **LiIon**.

<div><figure><img src="/files/qcY4fwNxjIOFU9WRscjU" alt=""><figcaption></figcaption></figure> <figure><img src="/files/YRoix3lKHmLcAWGvvkGg" alt=""><figcaption></figcaption></figure> <figure><img src="/files/v7d6euGertfOI3VOOUHY" alt=""><figcaption></figcaption></figure> <figure><img src="/files/aeBVTkRm0SSb2JsLkKHO" alt=""><figcaption></figcaption></figure></div>

{% hint style="info" %}
Once set, the battery checker displays total voltage, cell voltage difference, battery type, remaining capacity (%), and the voltage of each cell.
{% endhint %}

<figure><img src="/files/GHhouUReMiA526ulqHxu" alt="" width="540"><figcaption></figcaption></figure>

{% hint style="danger" %}
**Always** fly with fully charged batteries **(at least 95%)**.&#x20;

**Voltage Matching (Dual Battery Operation)**

* When operating the UAV with two batteries, verify that the **voltage difference between the two batteries does not exceed 0.1 V**.
  {% endhint %}


---

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