> For the complete documentation index, see [llms.txt](https://docs.efento.io/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.efento.io/nb-iot-loggers/general-information/technical-data.md).
# Technical data
## Memory
Efento loggers are equipped with built-in memory capable of storing up to 100,000 records. When the memory becomes full, the oldest records are automatically overwritten by new ones (circular buffer).
The length of time this memory can cover depends on the measurement interval, which is user-configurable from 1 second to 10 days.
## Power Supply
Efento NB-IoT loggers are available in two power supply configurations, designed to match the requirements of your specific deployment environment.
### Power configurations
* **External Power Supply**: Powered via USB or 9-26V DC, this version features an integrated 1300 mAh Li-Po backup battery to ensure continuous operation during external power outages.
* **Replaceable Battery**: Powered by a high-capacity, replaceable battery pack consisting of an ER26500H cell paired with an SPC1520 capacitor (8500 mAh, 3.6 V), designed for long-term, autonomous operation.
More information on: [power supply safety](/nb-iot-loggers/general-information/safety-guidelines.md#power-supply), [battery replacement and proper disposal](/nb-iot-loggers/installation/replacing-the-battery.md).
## Measured values
Efento loggers are capable of monitoring a broad range of physical and environmental parameters. Each logger can support up to six channels, each assigned to a dedicated sensor or probe. Devices can measure over 25 different parameters, including temperature, humidity, air pressure, differential pressure, open/close status, pulse counts, VOC levels, and water leakage.
All features described in this manual apply to every sensor model, while some sensors offer additional model-specific configuration options, such as calibration.
For the complete and up-to-date list of supported sensors, including their accuracy and measurement ranges, visit [getefento.com](https://getefento.com/product-categories/bluetooth-low-energy-sensors/).
## Communication interfaces
### Narrowband IoT (NB-IoT)
Efento NB-IoT loggers leverage cellular technology compliant with the **3GPP Release 13** standard, delivering a transmission power of **23 dBm** to ensure robust signal penetration even in challenging environments. The loggers support a wide array of global frequencies across bands **1, 2, 3, 4, 5, 8, 12, 13, 17, 18, 19, 20, 25, 28, and 66**.
To optimize data efficiency and minimize energy consumption over the network, communication utilizes the **CoAP** ([RFC 7252](https://tools.ietf.org/html/rfc7252)) protocol - supporting both confirmable and non-confirmable data frames - with data payload serialized via **Protocol Buffers (protobuf)**. Data **transmission** **intervals** are completely user-configurable, ranging from **1 minute up to 10 days**, balancing data granularity with optimal battery longevity.
Users have full flexibility over network deployment, with network settings allowing either automatic or manual configuration of the APN and PLMN. Cellular network access is provided via a standard **Micro SIM (3FF)** slot, with an **Embedded SIM (eSIM)** option available upon request.
### Bluetooth Low Energy
Efento loggers use Bluetooth Low Energy (BLE) to communicate with smartphones and tablets. They utilize both BLE advertising and BLE connections for communication. For deployments where local wireless interaction is not required, the Bluetooth interface can be completely disabled to further maximize and extend the device's battery lifetime.
## Types of enclosures
Efento loggers are available in two enclosure types: **IP30** and **IP67**, each suited for different environments and measurement needs.
{% hint style="info" %}
**General guidelines for choosing the enclosure type:**
* For precise environmental measurements using the logger’s internal sensors, select **IP30**.
* If the logger will be exposed to moisture or harsh conditions, select **IP67** and use external probes.
{% endhint %}
### IP30 Enclosure
**Characteristics**
* **Protection level:** protected against solid objects larger than 2.5 mm, such as tools and thick wires, no protection against liquids
* **Airflow:** Allows free airflow, making it suitable for loggers that measure temperature, humidity or air quality using built-in sensors
* **Use cases:** Indoor environments, including offices, warehouses, laboratories, server rooms or other sheltered indoor environments
* **Material:** ABS, inflamable
* **Mounting**: 3M adhesive pad with acrylic glue
* **Advantages:**
* Provides the best measurement accuracy for built-in environmental loggers
* Smaller size, suitable for indoor use
**Size**
### **IP67 Enclosure**
**Characteristics**
* **Protection level:** Fully dustproof and waterproof.
* **Airflow:** The enclosure is airtight and does not allow airflow. Therefore, IP67 devices cannot be used for built-in measurements of temperature, humidity, or air quality. IP67 devices must use external probes when environmental monitoring is required.
* **Use cases:** Industrial environments, outdoor installations, places exposed to moisture, wash-downs, dust, or chemicals
* **Material:** ABS, inflamable
* **Mounting**: screws or cable ties
* **Advantages:**
* Provides strong protection against water and dust
* Suitable for installation in harsh environments or outdoor
**Size**
---
# Agent Instructions
This documentation is published with GitBook. GitBook is the documentation platform designed so that both humans and AI agents can read, navigate, and reason over technical content effectively. Learn more at gitbook.com.
## Querying This Documentation
If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question.
Perform an HTTP GET request on the current page URL with the `ask` query parameter, and the optional `goal` query parameter:
```
GET https://docs.efento.io/nb-iot-loggers/general-information/technical-data.md?ask=&goal=
```
`ask` is the immediate question: it should be specific, self-contained, and written in natural language.
`goal` is optional and describes the broader end goal you are ultimately trying to accomplish on behalf of the user. GitBook uses it to tailor the answer towards what is most useful for that goal.
The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.
Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.