> For the complete documentation index, see [llms.txt](https://help.verkada.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://help.verkada.com/new-alarms/configuration/alarm-panel-as-a-lan-expander.md).

# Alarm Panel as a LAN Expander

Expander Mode allows a second alarm panel to forward signals from its connected wired and wireless devices to the primary panel over the LAN. When a second supported panel is added to an alarm site, it automatically enters Expander Mode.

This is designed for sites with multiple buildings, such as schools, manufacturing campuses, and business complexes, where the buildings share a network but do not have conduit between them. Devices connected to the expander can be added to and managed from the same alarm site.

{% hint style="warning" %}

* An expander panel does not require an additional license.
* The expander panel inherits the site settings from the primary panel.
  {% endhint %}

***

### When to use Expander Mode

* Use Expander Mode when buildings share a single address, a single set of monitoring requirements, and a single operational identity. 
* Use separate alarm sites for buildings that are independent locations with their own addresses and dispatch requirements.

### Requirements

* Both panels must be added to the same alarm site in Command.
* Both panels must be connected to the same LAN and able to communicate with each other.
* The expander panel must be a BP52.

{% hint style="danger" %}

* Cellular backup is not supported on expander panels.
* Battery backup is supported. However, Command does not currently display the battery charge or indicate when an expander panel is running on battery power.
  {% endhint %}


---

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