# Getting started

## SIM card

Efento NB-IoT loggers are available in two options: with a plastic SIM card (micro SIM / 3FF) or an embedded SIM (on request). The SIM card must support NB-IoT.

If your device has an embedded SIM, you do not need to insert a SIM card. Logger will register on a network as soon as you power it up.

A Micro SIM card holder is placed on the PCB. In order to insert the SIM card you need to open the device enclosure.

{% hint style="danger" %}
**Make sure that the logger is off when inserting the SIM card. Inserting the SIM card when the device is on may damage the logger!**
{% endhint %}

## Battery

By default the logger comes with a battery pack 3.6V 6300 mAh.

{% hint style="danger" %}
**Danger of explosion if the battery is incorrectly installed. Replace only with the same or equivalent type.**
{% endhint %}

{% hint style="info" %}
**Protect the environment! Battery must be recycled or disposed of properly. Follow your local regulations and guidelines regarding the battery disposal procedure.**
{% endhint %}

## Logger’s startup

Once you insert a SIM card, switch on the device - open the enclosure and set the switch in the “ON” position. On the device startup:

1. Red and green LEDs blink every second for 15 seconds,
2. After that, if the device has started correctly, the green LED will turn ON for 3 seconds. Otherwise the red LED will turn ON for 3 seconds.
3. Next, until the first communication with the server LEDs flash alternately every 4 seconds.
4. If the first communication succeeds, the green LED blinks every 4 seconds otherwise the red LED blinks every 4 seconds.

From now on, the device operates, takes the measurements and saves them in the memory. Once the startup is finished, the LEDs will blink as described in the Product overview chapter.


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