Offshore monitoring buoy
Offshore monitoring buoy

CB-650 Data Buoy

The CB-650 offers a compact platform with convenient tower mounting for met sensors, navigation lights, and radar reflectors.



Solar powered buoy


The platform integrates three 30-watt solar panels on the tower with space for up to three 28 A-Hr batteries in the data well.

Solar powered data buoy


The stainless steel tower includes a top mounting plate for solar marine lights and radar reflectors. Mounts are also available for weather sensors, video cameras and other topside instruments.

data logger and telemetry well

Data Well

A 10-inch diameter by 22-inch tall data well provides a watertight housing for batteries, data loggers, sensors, and other hardware.

Data buoy sensor ports


The data well lid provides pass-through connections for sensors, power, venting, and more. When integrated with the optional NexSens X2-CB data logger, the system is truly plug-and-play.

Deploy underwater sensors

Top-to-Bottom Ports

Three 4-inch pass-through ports allow for sensors to be mounted underwater while securely routing the cable. Instrument deployment pipes and custom sensor mounts attach to 4-inch NPT bottom threads.

data buoy navigation beacon

Solar Beacon

The optional solar marine light has a one to four nautical mile range and securely mounts to the buoy top plate for maximum visibility.

Data logging buoy

Data Logging

The X2-CB data logger replaces the standard pass-through data well lid for turnkey systems. Alternatively, 3rd party data loggers can be integrated by the user inside the data well.

Cellular, radio and satellite telemetry

Wireless Communications

Communication options using the X2-CB data logger include Wi-Fi, radio-to-shore, cellular, and Iridium satellite.

Compact durable data buoy

Built to Last

Constructed of cross-linked polyethylene foam with a heavy polymer skin and an indestructible stainless steel frame, the CB-650 is designed for years of service.

Tech Specs

  • Hull Dimensions: 38" (96.52cm) outside diameter; 22" (55.88cm) tall
  • Tower Dimensions: 40” (101.60cm) tall, 7/8 tubular
  • Data Well Dimensions: 10.3” (26.16cm) inside diameter; 21.5” (54.61cm) tall
  • Weight: 215 lbs. (97.52 kg)
  • Buoyancy: 650 lbs. (294.84 kg)
  • Hull Material: Cross-linked polyethylene foam with polyurea coating & stainless steel deck
  • Tower/Hardware Material: 316 stainless steel
  • Mooring Attachments: 1 or 2 point, 3/4” eyenuts
  • Solar Power: (3) 32-watt 12 VDC solar panels


Do I need sacrificial anodes in any saltwater application?
Sacrificial zinc anodes are recommended for any buoy deployed in saltwater or brackish conditions. Sacrificial anodes prolong the life of the buoy and protect the stainless steel hardware and instrument cage from corrosion. Both the buoy frame and the instrument cage should have a sacrificial anode attached (2 per buoy). Check the anodes during each maintenance visit and replace when necessary, which is typically six months to one year depending on conditions.
Why is it called the CB-650 data buoy and why is it yellow?
CB stands for "Coastal Buoy". The number 650 denotes net buoyancy, the buoyant capacity of the buoy after hardware is installed. A safety yellow hull is a standard international practice and requirement of the U.S. Coast Guard to signify research buoys.
What applications require a radar reflector?
Radar reflectors are important in high traffic waterways to alert boats and vessels. While the lid on top of the hull has some radar reflecting qualities, adding a radar reflector will ensure radar visibility at any time. It is recommended for any offshore buoy to be fitted with a radar reflector and navigation light.
What is the difference between the CB-650, -950 and -1250?
In addition to buoyancy capability, the solar towers offer incrementally larger solar panels for projects with a heavier power load. The bigger the buoy, the more batteries can be stored in the data well for reserve power. The instrument hole diameters are 4 inches, 6 inches and 8 inches respectively in the three large buoy models.

Case Studies

Stone Lab Buoy Tracks Algae

Even before the Toledo Water Crisis, researchers at Stone Lab were concerned with the algae blooming in Lake Erie. With their location on the lake’s Gibraltar Island, it was easy for them to see the tides whipping up green stuff each day in the summer months. So long before the crisis, which took place in August 2014, scientists at the Ohio State University lab began working with engineers at NexSens […]

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Expanding Algal Bloom Monitoring Network

Just one year after the Toledo water crisis of August 2014, federal, state and local agencies have stepped up to make sure that cities around Lake Erie’s western basin continue to have access to safe drinking water. Much of assuring that requires around-the-clock monitoring of water quality conditions there. Since the western basin is so large, not just one monitoring platform will do. Accordingly, researchers and water quality managers from […]

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Great Lakes Buoy Networks

The Great Lakes region is a dynamic ecosystem that supports millions of people, plants and animals. Key to maintaining its vitality is making sure the waterways that sit at its base remain clean and healthy. To do that, scientists and water managers need steady, reliable data. They often get this information from buoy networks. There are many different Great Lakes buoy networks out there, which are largely supported by government […]

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