<p><span>NEMOSENSE is a family of ethernet (TCP/IP) based IoT data loggers developed by Dewesoft. Devices send data directly to the database using MQTT protocol and are designed for long-term or permanent monitoring. The first device, launched in 2023, is the NEMOSENSE-3xACC-MEMS, incorporating a 3-axial MEMS accelerometer.</span></p>

What is the highest available sample rate with the NEMOSENSE devices?

<div> <div><span style="color: #333333; font-family: arial, sans-serif;"><span>The device was developed for long-term, unattended, structural health monitoring projects, where relatively slow vibrations are expected. The sampling rate is, therefore, limited to 125 S/s and can be further increased up to 4k S/s on request in the future.</span></span></div> <span class="im"><span></span></span> </div>

What is the storage spaces size of the NEMOSENSE?

<div>The device stores the data on a 32 GB internal memory (standard). <span>The files on the internal memory are overwritten when the memory is full (with a standard 32 GB memory, this occurs after approximately two months of measurement at 125 S/s).</span></div>

Is it possible to analyze the data acquired by NEMOSENSE in DewesoftX software?

<div>The data acquired by NEMOSENSE devices is sent to Dewesoft<span> </span><span class="il">Historian</span>.<span style="font-family: arial, sans-serif;"> <span>Dewesoft <span class="il">Historian</span> is a server-based software package where data from NEMOSENSE devices and DewesoftX Measurement Units is merged and stored into the same InfluxDB time-series database. The data from the database can be imported into DewesoftX for in-depth analysis using DewesoftX <span class="il">Historian</span> View Client.</span></span></div>

Can NEMOSENSE live stream the data to database?

<div><span style="color: #333333; font-family: arial, sans-serif;"><span>The data is acquired and logged continuously, but it is only sent to the database every 10 minutes. There is still a continuous full-speed data stream available in the database, but it is uploaded once every 10 minutes. Live streaming from NEMOSENSE is planned in future versions.</span></span></div>

Will the data be lost if connection between NEMOSENSE and database drops?

<div>NEMOSENSE always logs the data and starts sending it to the server whenever a connection is available. When the connection with the server is reestablished, the oldest data will be sent first and catch up with the present data.</div>

How are NEMOSENSE devices synchronized?

<div><span>NEMOSENSE supports three synchronization options:</span></div> <ol> <li><span style="font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, 'Open Sans', 'Helvetica Neue', sans-serif; font-size: 0.9375rem; letter-spacing: 0px;"><strong>NTP synchronization:</strong> The devices are synced to a reference NTP server. Even when powered off there is a very precise RTC clock on the device that keeps track of the time. Therefore, when the device is powered up again, it will have a reasonably accurate absolute time. Sync delay between devices on the same network is within 10 ms. </span><span style="font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, 'Open Sans', 'Helvetica Neue', sans-serif; font-size: 0.9375rem; letter-spacing: 0px;">Other sync options (GPS) will follow in future versions.</span></li> <li><span style="font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, 'Open Sans', 'Helvetica Neue', sans-serif; font-size: 0.9375rem; letter-spacing: 0px;"><strong>GNSS synchronization:</strong> The NEMOSENSE GNSS (G-version) supports GNSS synchronization and enables several remote devices to be synchronized to a GNSS clock with 100 µs accuracy.</span></li> <li><span style="font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, 'Open Sans', 'Helvetica Neue', sans-serif; font-size: 0.9375rem; letter-spacing: 0px;"><strong>PTP synchronization:</strong> At the time of writing, this method is not yet supported in firmware but is supported in hardware; therefore, a future firmware upgrade will enable this functionality on all NEMOSENSE devices. PTP synchronization will enable all daisy-chained devices with a synchronization accuracy of 1 µs.</span></li> </ol>

What is the spectral noise density floor of the NEMOSENSE-3xMEMS device?

<div> <div> <div><span style="color: #333333; font-family: arial, sans-serif;"><span>The device has a </span></span><span> <span style="font-family: arial, sans-serif;">25 µg/√Hz spectral noise density and 50 </span> </span><span>µ</span><span>g RMS noise at ±2g and 6Hz bandwidth. Lower-noise options (</span><span>0,7</span><span>µg/√Hz.</span><span>) are possible on request.</span><span></span></div> </div> </div>

Is there a battery-powered NEMOSENSE?

<div>Yes. All the "NEMOSENSE-B" versions offer a built-in Li-Ion battery. The battery pack consists of four 3,6V Lithium-Ion batteries with a nominal 12Ah. The battery packs can also be<span style="font-weight: 400;"> used in conjunction with passive POE. In this case, they serve as UPS. Immediately when out of power, the device switches to battery power to prevent data losses.</span></div>

Can NEMOSENSE use cellular 4G/5G network to send data?

<div><span style="font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, 'Open Sans', 'Helvetica Neue', sans-serif; font-size: 0.9375rem; letter-spacing: 0px;">NEMOSENSE can be used in the LTE network to send data by adding an external LTE router. This is an example of a </span><a href="https://iot-shop.de/en/shop/product/mil-ur32-l04eu-p-w-milesight-ur32-l04eu-p-w-industrial-cellular-4g-router-pro-with-poe-and-wifi-5684#attr=6224,6227,6219,6223,6226,6225,6220,6222,6213,6218,6215,6221,6217,6216" target="_blank" rel="noopener" style="font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, 'Open Sans', 'Helvetica Neue', sans-serif; background-color: #ffffff; font-size: 0.9375rem; font-weight: 400; letter-spacing: 0px;">3rd-party PoE LTE router</a><span style="font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, 'Open Sans', 'Helvetica Neue', sans-serif; font-size: 0.9375rem; letter-spacing: 0px;">. </span><span style="font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, 'Open Sans', 'Helvetica Neue', sans-serif; font-size: 0.9375rem; letter-spacing: 0px;">A fully integrated LTE NEMOSENSE device is planned in near future.</span></div>

12 reviews

NEMOSENSELow-noise vibration data logger and IoT device

Name: NEMOSENSE
Brand: Dewesoft®
Rating: 4.8 (19 reviews)

NEMOSENSE is a tailor-made IoT device that combines a vibration data acquisition device, a data logger, and a low-noise triaxial MEMS accelerometer. It is an ideal vibration monitoring solution for permanent condition monitoring of wind turbines and structures such as bridges, buildings, antennas, and stadiums. It offers a great price-performance ratio.

1 kS/s/ch

-20°C to +60°C

Vibrations

Acceleration

Displacement

Velocity

Angle

Ethernet

PTP synchronization

IRIG and GPS timecode

4G/LTE

Battery

SD card

IP67

NEMOSENSE highlights

All-in-one data logger

NEMOSENSE is a data logger and data acquisition device with an embedded low-noise triaxial MEMS accelerometer. It performs the analog-to-digital conversion and offers an ethernet TCP/IP data interface.

Daisy chain

Multiple NEMOSENSE devices can be daisy-chained and synchronized via standard Ethernet network cable.

PTP synchronization

NEMOSENSE daisy-chained devices can be synchronized with a precision of 1 μs using the Precision Time Protocol (PTP). When connected to the same network, all devices achieve synchronization within 10 ms using the Network Time Protocol (NTP).

Onboard processing

NEMOSENSE includes a small microprocessor. This allows setting up and calculating simple calculations like FFT's, RMS, P-P, and other statistical caluclations directly onboard.

Low noise density

The NEMOSENSE data loggers have a very very low noise performance of 25 μg√Hz spectral noise density at the 2g measurement range.

Internal storage

NEMOSENSE devices have 32 GB of internal storage memory and can save up to 1 month of measured data at 125 S/s.

NTP synchronization

NEMOSENSE devices that are connected on the same network are synchronized within 10 ms using NTP synchronization (Network Time Protocol).

Great price/performance

The NEMOSENSE offers a good price vs. performance ratio and is thus perfect for system integrators, and large continuous monitoring installations.

Waterproof enclosure

NEMOSENS enclosure is fully waterproof with Harting push-pull RJ45 connector. It offers IP67 environmental protection.

Battery power

We offer a battery-powered NEMOSENSE device for completely autonomous operation.

4G/LTE connectivity

NEMOSENSE devices can be optionally equipped with a 4G/LTE modem, allowing you to send and access your data via the cellular network.

Dewesoft quality and 7-year warranty

Enjoy our industry-leading 7-year warranty. Our data acquisition systems are made in Europe, utilizing only the highest build quality standards. We offer free and customer-focused technical support. Your investment into the Dewesoft solutions is protected for years ahead.

NEMOSENSE overview

NEMOSENSE is a low-power IoT device equipped with an integrated triaxial MEMS accelerometer. It collects data and stores it on an internal SD card in CSV format. When a connection is available, data is transmitted to the server using the MQTT protocol.

The device features an onboard ADC converter for analog-to-digital conversion, eliminating noise picked up by analog cabling.

A built-in microprocessor handles simple processing tasks, such as FFT and basic statistics (Minimum, Maximum, Average, RMS), removing the need for an expensive external computer.

Device options

You can combine various options and measurement types for NEMOSENSE devices. Here are some example configurations:

NEMOSENSE-3xMEMS-ACC: Ethernet connectivity and triaxial MEMS accelerometer.
NEMOSENSE-B-3xMEMS-ACC: Ethernet connectivity, battery-powered, triaxial MEMS accelerometer.
NEMOSENSE-M-3xMEMS-ACC: Ethernet connectivity, G4/LTE connectivity, triaxial MEMS accelerometer.
NEMOSENSE-G-3xMEMS-ACC: Ethernet connectivity, GPS/GNSS, triaxial MEMS accelerometer.
NEMOSENSE-BM-3xMEMS-ACC: Ethernet connectivity, G4/LTE connectivity, battery-powered, triaxial MEMS accelerometer.
NEMOSENSE-BG-3xMEMS-ACC: Ethernet connectivity, battery-powered, GPS/GNSS, triaxial MEMS accelerometer.
NEMOSENSE-MG-3xMEMS-ACC: Ethernet connectivity, G4/LTE connectivity, GPS/GNSS, triaxial MEMS accelerometer.
NEMOSENSE-BMG-3xMEMS-ACC: Ethernet connectivity, G4/LTE connectivity, battery-powered, GPS/GNSS, triaxial MEMS accelerometer.

NEMOSENSE devices (standard, with 4G/LTE, and with 4G/LTE/GNSS)

NEMOSENSE connectivity

All NEMOSENSE devices can connect to an existing Ethernet TCP/IP network or via mobile 4G/LTE networks (with the Mobile option) to send data to the Dewesoft Historian service, a time-series database for long-term data storage.

In addition to web clients, the data can be accessed and analyzed using the award-winning DewesoftX software, typically running on a client PC in an engineering office. The DewesoftX view client includes two modules:

Historian client: The MQTT client operates in DewesoftX’s measure mode, and displays live data from the measurement units.
Historian importer: The Historian Importer plugin operates in DewesoftX Analysis mode, allowing data from a chosen time frame to be loaded into a DewesoftX data file for in-depth analysis and reporting.

Additionally, CSV files can be retrieved from the device's internal storage via the NEMOSENSE configuration app.

Powering options

All NEMOSENSE devices can be powered using passive PoE (Power-Over-Ethernet) or via built-in batteries with the battery pack option (NEMOSENSE-B).

The battery pack consists of four 3.6 V Lithium-Ion batteries with a nominal capacity of 12Ah.

NEMOSENSE with a battery-power option is ideal for temporary vibration monitoring campaigns. It allows for 7 days of continuous logging or two days of continuous streaming at 125 S/s without recharging.

The battery pack can also be used in conjunction with passive POE, serving as a UPS. If the power goes out, the device immediately switches to battery power to prevent data loss.

Internal battery for powering NEMOSENS vibration loggers

Synchronization options

The NEMOSENSE device supports the following data synchronization options:

NTP synchronization: When NTP time is available, the device continuously adjusts its clock to match the NTP time. The synchronization difference between NEMOSENSE devices on the same network with a local NTP server is typically within 10 ms, depending mainly on network latency. NTP synchronization is available on all NEMOSENSE devices.
PTP synchronization: Currently not supported in the firmware but supported in the hardware. A future firmware upgrade will enable this functionality on all NEMOSENSE devices, allowing daisy-chained devices to achieve synchronization accuracy of 1 µs.
GNSS synchronization: Available if the GNSS (G) option is ordered. GNSS allows multiple remote devices to be synchronized to a GNSS clock with an accuracy of 100 µs.

NEMOSENSE with GNSS/GPS and 4G/LTE capability

Device architecture

NEMOSENSE-3xMEMS-ACC is an Ethernet device and can be easily connected to an existing TCP/IP network. The MQTT Client is running onboard sending the data to the MQTT broker, a Dewesoft Historian component, installed on the server side.

Dewesoft Historian is a central point where data from NEMOSENSE devices, Dewesoft Measurement Units, and 3rd party MQTT clients is merged and stored into the same InfluxDB time-series database.

The data stored in the database can be accessed using a web browser (Grafana) or DewesoftX software.

Seismic noise performance

With only 25 µg/√Hz spectral noise density and 100 µg residual noise at 50 Hz bandwidth, the NEMOSENSE-3xMEMS-ACC device is a cost-effective solution for seismic measurements.

The FFT recorder on the image shows the residual noise of the three axes measured with an integrated accelerometer at the sample rate of 100 S/s resulting in a 96 dB dynamic range.

FFT graph illustrating the residual noise of the three axes

Product testing and validation

Hardware repairs or replacements are expensive on structures such as bridges. Therefore NEMOSENSE-3xMEMS-ACC was put through in-depth product validation tests that ensure reliable operation within its specifications.

Standard testing procedures include vibration and temperature cycle tests to check the durability and specify drifts in measured acceleration.

Historian database storing

NEMOSENSE dataloggers can be installed for long-term or permanent monitoring. This kind of measurement requires efficient data storage. For that, we provide Dewesoft Historian service. The Historian is a time-series database service based on the MQTT messaging protocol for the Internet of Things (IoT).

The Historian is based on an open-source InfluxDB database and is a perfect solution for long-term monitoring. Data in the Historian can be accessed in two ways:

Web clients: any modern web browser can be used as a web client to access real-time data stored in the Historian. The solution is based on another open-source project Grafana. It allows to set up of completely customized views and is a perfect solution for real-time dashboards.
Desktop client: the desktop client is an instance of our award-winning DewesoftX software. It allows you to import historical data from the Historian database for in-depth analysis.

The Historian is available to be installed on your own server (Windows, Linux, Mac OS) or as a completely managed cloud service.

Visit the Dewesoft Historian web page for more information.

Permanent outdoor mounting

NEMOSENSE-3xMEMS-ACC devices are supplied in a waterproof aluminum casing with RJ45 Harting push-pull connector. The enclosure is designed to be mounted outdoors and is fully waterproof and complies with IP67 environmental rating.

The outdoor enclosure automatically vents the air to equalize pressure inside the enclosure to the outside air pressure while it does not allow water to pass into the enclosure. This prolongs the life span of the seal and increases the durability of the enclosure.

Applications

NEMOSENSE-3xMEMS-ACC devices are designed for tailor-made structural health monitoring solutions and seismic monitoring solutions and are thus ideal for permanent health condition monitoring on big structures such as: