NB-IoT
Wireless water level logger
Efento NB-IoT wireless liquid level loggers deliver continuous, high-precision water level monitoring for environmental and industrial applications – from wells, retention systems, and water supply installations to wastewater treatment plants, groundwater level control, and water resource management. Equipped with an external 15-meter hydrostatic probe, it enables accurate depth and water column measurements in submerged or hard-to-access sites while keeping the main data logger safely mounted above ground.
By transmitting data directly over the cellular network (Narrowband IoT), the device operates completely independently – requiring no gateways, routers, or local Wi-Fi configuration. The integrated Bluetooth Low Energy interface enables quick, intuitive setup via smartphone in under 15 minutes, while its open architecture ensures seamless integration with Efento Cloud or any third-party IoT platform.
- Probe length: 15 m as standard, with other lengths available on request
- Flexible Power Options: Choose between a long-life primary battery offering up to 8 years of maintenance-free operation, or a rechargeable USB-C variant (1,300 mAh)
- Expanded internal memory: Stores up to 100,000 measurements, ensuring zero data loss during network disruptions
- Configurable intervals & instant alarms: Flexible logging (5 seconds to 7 days) with immediate alerts when safe thresholds are breached
- Easy setup & remote management: Quick configuration via mobile app in under 15 minutes
Key features
Efento Cloud Platform
Complete solution for continuous monitoring, customizable dashboards, instant SMS/VMS/PUSH/email threshold alerts, and automated reporting.
Long battery life
Engineered for long-term, maintenance-free operation (up to 8 years on battery) or available in a rechargeable USB-C variant.
No Gateways Required
Transmits data directly over the cellular network (NB-IoT). With no local routers, gateways, or complex Wi-Fi configuration needed, you significantly reduce both installation and maintenance costs.
Easy Set Up
Quick local configuration using a smartphone and Bluetooth LE mobile app. Up and running in under 15 minutes without specialized IT skills.
Data Safety & Internal Buffer
Internal memory stores up to 100,000 measurements. If cellular connectivity is temporarily lost, all log data is safely saved and automatically transmitted once connection is restored.
Integration
Standard CoAP protocol and open APIs enable seamless integration with any 3rd-party cloud platform, SCADA, or custom software.Edge analytics & smart transmission
The logger can process measurement data locally and optimize when information is transmitted. This helps reduce unnecessary cellular communication and supports long battery life while ensuring important events are reported promptly.Remote configuration & firmware updates
Manage devices remotely without on-site visits. Configuration changes and firmware updates can be delivered over the air, helping reduce maintenance effort and keeping deployed devices up to date.Custom factory configuration
Devices can be supplied with a customer-specific configuration prepared before shipment. Measurement intervals, transmission settings, APN, PLMN, and other parameters can be preconfigured according to project requirements, reducing installation time and simplifying large-scale deployments.Customer-provided SIM cards
The logger can operate with SIM cards supplied by the customer, allowing the use of a preferred local mobile operator and existing connectivity agreements. This gives customers greater flexibility in regions where their own operator provides the best NB-IoT coverage or commercial conditions.Optional IP68 waterproof enclosure
For applications requiring maximum protection against dust and water, the sensor can be supplied in an optional IP68 waterproof enclosure. The enclosure is fully dust-tight and designed to withstand prolonged immersion in water under specified conditions, making it suitable for demanding industrial, outdoor, and high-moisture environments.
| WATER LEVEL PROBE | Model: Hefei WNK 8010, 15-meter probe Measurement range: 0-15 m Accuracy: 0,5% FS Resolution: Default 1 mm (user-configurable) Drift: 0,2% FS/ year Protection class: IP68 |
|---|---|
| DATA LOGGING | Measurement interval: 5 s – 7 days (user-configurable) Memory size: 100 000 measurements |
| BLUETOOTH INTERFACE | Radio module frequency: 2,4 GHz Power: 2,5 mW (4 dBm) Range: up to 100 m (LOS) Transmision period: 1 s Bluetooth version: Bluetooth Low Energy (4.0) |
| NB-IoT INTERFACE | NB-IoT bands: 3GPP: 13 i 14 (LTE Cat NB2) Power: 23 dBm ±2 dB |
| COMMUNICATION | Protocol: CoAP Trasnsmission interval: 1 min – 7 days (user-configurable) |
| OPERATING & STORAGE CONDITIONS | Main unit operating conditions; temperature: -25°C to +70°C, humidity: 0-99% RH (non-condensing) Probe operating conditions; temperature: -40°C to +85°C Storage conditions; temperature: -25°C to +70°C Charging conditions (variants with external power supply); temperature: 0°C to +45°C |
| CERTIFICATIONS | Regulatory: CE (RED), FCC Environmental: RoHS |
| SOFTWARE UPDATES | Over the air (with delta mechanism); Over Bluetooth Low Energy |
| VARIANTS | Variant 1: Variant 2: Variant 3: Variant 4: |
NOT SURE YET?
Order a starter kit - $165 only
The offer is dedicated to companies only.
Check it yourself. The starter kit includes all you need to test Efento wireless sensors and Efento Cloud platform:
- NB-IoT temperature and humidity sensor
- Efento Cloud access
- Free shipping worldwide
Our customers
Newsletter September 2026
Efento Cloud for hospitals – safety, savings and full control
A hospital consists of thousands of processes, devices, and rooms whose proper functioning is essential for patient safety. One of these is ensuring proper storage conditions for medicines, vaccines, medical supplies, and laboratory samples.Efento devices can also monitor gas and liquid pressure, water leaks, and visitor footfall.
Efento Cloud enables automated monitoring and control.
Automated pressure warning systems
Pressure sensors are installed in water, oil, chemical, or compressed air pipelines for continuous pressure monitoring. In the event of a pressure issue, a PLC controller operates a pump or valve to immediately increase or decrease the pressure. However, most pressure sensors only provide control signals and lack alerting capabilities.Is it necessary to archive reports from the Efento system?
Data from temperature loggers used in the storage and transport of vaccines must be kept for at least 5 years. In the case of the Efento system, measurement data from the loggers is stored for 6 years. To ensure that nothing is lost (e.g., due to a failure), it is simultaneously saved in two independent data centers (AWS servers).We were busy deploying 150,000 NB-IoT sensors – The Things Conference
The 9th edition of The Things Conference—the premier global IoT event held on September 22–23, 2026, in Amsterdam—brought together over 2,500 experts from around the world.We are proud to have been a Bronze Partner of this conference.
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