# Set Up Universal Transmitter Mode on a BR31

{% hint style="success" %}
This article is a guide for classic Alarms. Refer to this [article](/new-alarms/installation/set-up-universal-transmitter-mode-on-a-br31.md) if you have new Alarms. See [New Alarms vs Classic Alarms](/new-alarms/getting-started/new-alarms-vs-classic-alarms.md) if you are unsure which version of Alarms you have.
{% endhint %}

***

The [Verkada BR31 wireless door sensor](https://docs.verkada.com/docs/br31-quick-start-guide.pdf) can be used as a universal transmitter, enabling wired alarm devices to communicate wirelessly with Verkada wireless hubs.

{% stepper %}
{% step %}
**Collect the required components, including the main body of the BR31, a T10 Torx screwdriver, and the wired sensor.**

<div align="left" data-with-frame="true"><img src="/files/EgTRI5XSUI2srLZG2SE7" alt=""></div>
{% endstep %}

{% step %}
**Use the T10 Torx screwdriver to unscrew the Torx screw on the underside of the BR31. Remove the backplate of the unit.**

<div align="left" data-with-frame="true"><img src="/files/IzGW7ZwYOwEJVn6Os7vS" alt=""></div>
{% endstep %}

{% step %}
**Plug the leads of the wired alarm sensor into the 2 inputs at the top of the BR31 unit. Polarity does not matter in this case.**

<div align="left" data-with-frame="true"><img src="/files/2c2TdhxtABRO9IK6Z2fn" alt=""></div>
{% endstep %}
{% endstepper %}

***

## Command set up

{% hint style="danger" %}
[Add the device](/command/organization-settings/add-a-device-to-your-command-organization.md) to Command before you continue.
{% endhint %}

{% stepper %}
{% step %}
**Navigate to the Devices page in the alarm site.**

1. Select a sensor.
2. At the top right, click <i class="fa-ellipsis">:ellipsis:</i> > click **Edit Sensor**.
   {% endstep %}

{% step %}
**In the device settings:**

1. Toggle on **Universal Transmitter Mode**.
2. Select the normal state of the sensor (see specific, relevant sensor). Wired door contact sensors are commonly "Normally Closed".
3. Click **Done** and wait a few minutes for the new configuration to update on the BR31.
   {% endstep %}

{% step %}
**Manually trigger the wired sensor to confirm that the BR31 is transmitting the sensor events to Command.**
{% endstep %}

{% step %}
**Once device performance is confirmed, follow the mounting steps in the** [**BR31 Install Guide**](https://docs.verkada.com/docs/br31-quick-start-guide.pdf) **to complete the installation.**
{% endstep %}
{% endstepper %}


---

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