NexSens X2-CB Buoy-Mounted Data Logger

User Guide



The X2-CB is an all-in-one environmental data logger specifically designed for use with a NexSens CB-Series data buoy. It features wireless communication, a large plug-and-play sensor library, and ultra-low power consumption. The unit includes diagnostic Wi-Fi connectivity with options for dedicated radio, cellular & satellite telemetry. WQData LIVE web datacenter provides instant access on any web browser.



First-Time Setup
What’s Included1.1
Common Accessories
Sensor Connections2.2
Apply Power2.3
Sensor Auto-Detection2.4
Quick Start Guides2.5
WQData LIVE3.1
About WQData Live Data Center3.2
Creating a WQData Live Account3.3
Creating a Project on WQData Live3.4
Adding a Data Logger to a Project3.5
Configure Telemetry4.1
Diagnostic Measurements
Diagnostic Measurements on WQData Live5.1
Buzzer Pattern Indicator5.2
Additional Resources 
How To5.4
Replacing a desiccant

First Time Setup

1.1 What’s Included

The NexSens X2-CB Buoy-Mounted Data Logger includes the following accessories and spare parts for start-up and maintenance.

  • (5) Sensor port plugs
  • (1) Power port plug
  • (1) Wireless antenna (Pre-installed)
  • (1) Quick start guide
  • (2) Spare UW-Plugs
  • (1) Tube of O-ring grease
  • (2) Spare 2X15 mm O-rings
  • (3) Spare 116 O-rings

X2-CB base components

X2-CB Maintenance Kit



1.2 Common Accessories

The following are common accessories to the X2 Environmental Data Logger for direct connection, mounting, power, and sensor connection.

BuoysDirect ConnectionPowerPressure Relief Vents
CB-150 Data Buoy

NexSens X2/V2 Direct Connect USB PC Cable

NexSens CB-A01 Data Buoy Battery Harness

NexSens UW-PRV Pressure Relief Valve

CB-450 Data Buoy



NexSens CB-A05 Data Buoy Battery Harness



CB-650 Data Buoy

NexSens CB-Series Battery Float Charger Kit

CB-950 Data Buoy

CB-1250 Data Buoy



2.2 Sensor Connections

Note that certain sensors require configuration prior to interfacing with an X2-series data logger. Sensors that are deemed ‘plug and play’ and those requiring additional configuration are detailed in the X2 Supported Sensors page. For guidance on a specific sensors’ configuration, visit the sensor section of the NexSens Knowledge Base by clicking the logo below. Alternatively, review the CONNECT software guides on creating generic scripts to interface an X2 with unsupported sensors that utilize standard communication protocols (SDI-12, Modbus RTU etc.).


Link to NexSens Knowledge Base



The X2-CB incorporates five sensor ports (P0-A, P0-B P1-A, P1-B & P2) for connection to industry-standard digital interfaces including RS-232, RS-485 and SDI-12.

Note: Only three RS-232 sensors can be connected to an X2. Each must occupy a uniquely numbered port (i.e. P0, P1, or P2).

Connect all sensors to the X2-CB using any combination of the five available sensor ports after removing the pre-installed blank plugs. For full systems configured and tested by NexSens, ports may be labeled for a each specific sensor. In those instances, establish the connections as directed.


X2-CB Sensor Ports



Power: Each sensor port can supply a maximum of 1.5A current. Total sensor port current draw must not exceed 2A.

Important:  Record the port number (P0-A, P0-B, P1-A, P1-B or P2) occupied by each sensor.  After the initial setup, sensors must always be reconnected to the same port for proper communication.


2.3 Apply Power

Power is applied through the X2-CB’s 6-pin port once the solar panel plug is connected. The solar panel plug contains an internal jumper that completes the power supply circuit, allowing the battery to supply power to the data logger while the panels continue to charge the battery. Remove the blank port plug and apply power to the system by inserting the 6-pin plug from the solar tower into the 6-pin port labeled COM/SOLAR. While applying power:

  • Listen closely for the diagnostic beeps from the data logger
    • 1 immediate beep confirms the power connection
    • 2 beeps after ~20 seconds affirms a strong telemetry signal
    • 3 beeps after ~20 seconds indicates a weak telemetry signal (Try relocating the buoy or logger)

6-pin COM/SOLAR port

Data buoy solar tower


While in storage, the battery may be recharged with a NexSens CB-Series Battery Float Charger Kit.


2.4 Sensor Autodetection

Following power connection, the logger will automatically begin to scan through a list of enabled sensors scripts to compile a sensor list. Sensors discovered during this process will automatically be updated on WQData LIVE via the X2’s on-board telemetry.

Sensor detection will take approximately 10 minutes. Leave the full system connected and powered while proceeding through the WQData LIVE setup. Following detection, sensor readings will be logged and uploaded at a 10 minute interval until adjusted by the user.


2.5 Quick Start Guides

Follow the Quick Start Guide links below to set up your X2 system.







3.1 WQData Live

3.2 About WQData LIVE Data Center

WQData LIVE interface


WQData LIVE is a Cloud Data Center used in conjunction with the X2-CB data logger to:

  • Upload and store logged data
  • Generate and Export historical data reports
  • Monitor logger diagnostics
  • Remotely configure logger settingsa


3.3 Creating a WQData Live Account

A WQData Live account gives the user access to create projects, set up logger transmission and create a historical and real-time data record from the X2-CB. Follow the link below to set up a WQData Live account.

Creating a WQData LIVE Account


3.4 Creating a Project on WQData Live

Creating a WQData Live project allows the user to provide a centralized location for data transmission from the X2-CB. Follow the link below to create a WQData Live project.

Creating a Project on WQData Live


3.5 Adding a Data Logger to a Project on WQData Live

Adding a Data Logger to a Project on WQData Live 


Visit the WQData LIVE Web Datacenter page on the NexSens Knowledge Base to learn more about the capabilities of WQData LIVE.



4.1 Configure Telemetry

Note: Most cellular and iridium systems will be pre-configured by NexSens for plug-and-play transmissions to WQData LIVE.  Wi-Fi and user-configured data accounts may require setup.

Wi-Fi –Establish permanent wireless data transmission for standard X2s.

Cellular- a 4G Compliant Mini-SIM card is required for installation on cellular models of the X2-CB. Factory-installation is recommended, but user installation is possible.

Iridium– Factory-installed Iridium satellite modems allow for communication in the most remote deployment locations.



CONNECT is a software utility that enables users to interface directly with any NexSens X2-Series data logger using a NexSens X2/V2 Direct Connect USB PC Cable. It supports a growing number of diagnostic and configuration tools to facilitate system setup and troubleshooting.



Visit the CONNECT Software page on the NexSens Knowledge Base to learn more about the capabilities of CONNECT



5.1 Diagnostic Measurements on WQData Live

All X2 data loggers contain 12 meta diagnostic parameters that monitor the system’s health. Follow the link below to learn about the acceptable value ranges and troubleshooting options available for proper system maintenance.

Logger Diagnostic Readings


5.2 Buzzer Pattern Indicator 

Follow the link below to view information regarding the Buzzer Patter Indicator displayed by the X2-CB.

What does the buzzer pattern indicate?


Additional Resources

5.3 Troubleshooting

Visit the X2-CB Troubleshooting Section of the NexSens Knowledge Base to learn effective troubleshooting strategies for the X2-CB.



5.4 How To

Visit the X2-CB How To Section of the NexSens Knowledge Base to learn advanced and user-friendly ways to utilize the capabilities of the X2-CB.

How To


5.5 FAQ

Visit the X2-CB FAQ Section of the NexSens Knowledge Base to find answers to common questions asked about the X2-CB from NexSens customers.






6.1 Replacing Desiccant

Each X2-CB ships with a bag of desiccant for internal moisture control. Maintaining proper internal humidity is vital for the longevity of the system. Follow the link below to learn how and when a desiccant should be replaced.

Desiccant Replacement 


6.2 Storage

Although year-round deployment is available with the X2-CB data logger, some systems are only utilized during field season when data is crucial. Before storing your system over the off-season follow the link below to learn best practices for X2-CB system storage.

Storage Requirements




6.3 Links

In the event that NexSens systems require maintenance or repair, fill out our service request form.

NexSens Return Materials Authorization