NexSens Technology CB-250 User manual

CB-250 Data Buoy
User Guide
Last Revision: 28 April 2023
Date Generated: 28 April 2023
Copyright © 2023 NexSens Technology, Inc.

Table of Contents
1. General
CB-250 Data Buoy Overview
Key Components and Definitions
Key Specifications
CB-Series Data Buoy Planning & Precautions
Buoy sizing and power budget
Buoy ballast
Buoy mooring
Electrical connections
Safe deployment
2. Buoy Assembly
Using NexSens Electronics in CB-Series Data Buoys
Data Loggers
Battery Packs
Accessories
Creating a Parts List
Custom Data Buoy Configuration Guide
Selecting a Buoy Platform
Selecting a Data Well Lid
Selecting Accessories
Creating a Parts List
Installing User-Supplied Electronics in CB-Series Data Buoys
Common Accessories
Securing Data Well Plate
CB-PTL Bulkhead Connector Assembly Installation
Connector Types
UW-6 Power Bulkhead Connector Assembly Wiring
UW6-BULK Pinout
Wiring Options
CB-MCL Bulkhead Connector Installation
Connector Types
M550 Beacon for CB-Series Data Buoys
Installation
Operation
CB-Series Data Buoy Instrument Cage Installation
CB-CCA Anti-Rotation Collar
Use of Sacrificial Anodes on CB-Series Data Buoys
NexSens Sacrificial Anodes
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Zinc as Anode Material
CB-Series Data Buoy Instrument Mounts
Topside Buoy Instrument Mounts
Subsurface Buoy Instrument Mounts
3. Deployment
CB-Series Data Buoy Ballast Weight & Stability
Top-Side Weight
Ballast Weight
Buoy Ballast Weights
Mooring Data Buoys
Buoy Ballast
Mooring Eye Lifting
Data Buoy Mooring Types
CB-Series Data Buoy Deployment Tips
NexSens CB-Series Data Buoys
Connecting Mooring Hardware
Buoy Deployments
Single-Point Mooring Buoy Deployments
Two-Point and Three-Point Mooring Buoy Deployments
Planning a Medium-Deep Water Mooring for Small Data Buoys
Medium-Deep Water Deployment Considerations
Mooring Hardware Materials
Deployment
4. Troubleshooting and Maintenance
General Data Buoy Maintenance
Immediate Steps for Buoy Maintenance
Preparing for Re-deployment
Verify Battery Voltage of a CB-Series Buoy
Replace a Battery in a CB-Series Data Buoy
Tools Required
Data Well Lid Removal
Battery Removal
New Battery Installation
Buoy Plate Re-installation
Test a CB-Series Buoy Solar Tower
Data Buoy Storage Requirements
Storage Requirements
Preparing for Re-Deployment
5. Warranty
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6. Service Request
Service Request
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1. General
CB-250 Data Buoy Overview
The CB-250 data buoy strikes a balance between compact and easy to deploy, yet buoyant
and powerful enough to be deployed in larger water bodies including lakes, rivers, coastal
waters, harbors, estuaries and other freshwater or marine environments. Like all solar-
powered NexSens CB-Series data buoys, it is a highly customizable platform that may be
configured with NexSens or user-supplied electronics. It supports a wide variety of topside
and subsurface sensors and measurement instruments.
Key Components and Definitions
Buoy Hull
Constructed of cross-linked polyethylene foam with a durable polymer outer layer and
rugged stainless steel frame providing a net buoyancy of 250 lb (114 kg). Three 2” pass-
through holes with female NPT bottom threads allow for quick connection of instrument
deployment pipes and custom sensor mounts.
Data Well
The waterproof compartment located in the center of the buoy hull for placement of system
electronics such as batteries and data loggers. On the CB-250 model, the data well has a
10.3” (26.2 cm) diameter and 19.5″ (49.5 cm) height.
For complete NexSens systems, the data well is fitted with a CB-A01-2 or CB-A05 battery
harness and the X2-CB data logger, which has (5) waterproof UW sensor ports supporting
common standards such as SDI-12, RS-232 and RS-485. Waterproof sensor connection is
achieved by factory installation of sealed UW connectors on sensor cables.
Figure 1: CB-250 data buoy.
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For users supplying their own electronics, the CB-250 is delivered as an open platform with
empty data well or with battery only. A data well top plate can be supplied in many
configurations, for example:
1. A standard CB-PTL Pass Through Lid for passing of instrument cables through gland
fittings
2. A CB-PTL lid with UW8-BULK sensor bulkhead cable assemblies
3. A CB-MCL Wet-Mate Lid for use with marine-grade bulkhead connectors
4. A blank lid with only UW6-BULK power cable assembly and vent that users may drill
their own holes and install connectors into
5. No lid, only a drawing showing bolt hole locations for users who want to machine their
own lid
Solar Tower
Three 15W solar panels capture sunlight from any direction and charge batteries located
inside the data well. The tower also supports the mounting of an M550 solar marine light
for nighttime visibility. Aside from regular cleaning to ensure solar panels are unobstructed
from receiving maximum sunlight, there is little to no maintenance required. However,
solar assemblies may be function tested if any performance issue is suspected by placing
in the sun and measuring output on the UW-6 (6-pin) port plug.
Figure 2: Buoy data well
and pass-through holes.
Figure 3: Data well top
plate.
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Buoy Frame
The skeleton of the buoy is comprised of 316 stainless steel with topside lifting eyes and
subsurface mooring eyes for single and multi-point moorings. The frame supports
attachment of an instrument cage for secure connection of subsurface sensors and
additional ballast weight for stability.
Key Specifications
The key specifications of the CB-250 buoy are given below:
Hull Outer Diameter: 30.0” (76.2cm)
Hull Height: 20.0” (50.8cm)
Data Well Inner Diameter: 10.3” (26.2cm)
Data Well Height: 19.5″ (49.5cm)
Pass-Through Hole Diameter: 2.0″ (5.1cm)
Tower Height: 20.0” (50.80cm)
Figure 4: CB-250 solar tower.
Figure 5: CB-250 buoy
frame with instrument cage
installed.
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Solar Panels: 3x 15-watts
Weight: 115 lb (52kg)
Net Buoyancy: 250 lb (114kg)
Hull Material: Cross-linked polyethylene foam with polyurea coating & stainless steel
deck
Hardware Material: 316 stainless steel
Mooring Attachments: 3x 3/4” eyenuts
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CB-Series Data Buoy Planning & Precautions
Buoy deployments are usually complex operations that involve many elements including
sensors, data loggers, mounting hardware, and mooring equipment. Careful planning and
precautions are essential to the success of a buoy project, not only for system operation
and data collection but also to ensure the safety of project personnel and minimize the risk
of damage to expensive system components. When planning a buoy deployment, be sure
to give careful consideration to the following aspects:
Buoy sizing and power budget
Buoys come in various physical sizes with differing battery and solar charge capacities. A
buoy must be adequately sized to tolerate the site environmental conditions while
providing sufficient power for continuous system operation. A power budget should be
analyzed to ensure the system can meet the demand for sensor measurements and data
transmission.
Buoy ballast
Proper ballast of a buoy is critical to buoy stability when it is deployed in the water. Be sure
to review the ballast weight and stability guide when designing a buoy system. Some
experimentation may be required before final deployment.
Buoy mooring
Mooring systems come in many forms depending on the location, water depth, and
environmental conditions to which a buoy will be exposed. As a starting point, the mooring
data buoys guide provides an overview of common mooring strategies. However, NexSens
does not endorse any particular mooring strategy, and systems should be designed and
executed based on careful consideration and local knowledge of the deployment site.
Electrical connections
Many NexSens buoy systems utilize UW connectors for connection of power and sensor
cables. Data loggers such as the X2-CB have UW receptacle ports to receive sensor cables
fitted with UW plug connectors. UW connectors provide a double O-ring seal, with one O-
ring inside the receptacle and one around the plug. In order to ensure waterproof
connection, check the following each time a UW connection is made:
1. The O-ring inside the receptacle is present (has not fallen out)
2. The receptacle and plug are clean, dry and free of debris
3. The O-ring on the plug is lightly greased
4. Connection is tight, secure and fully seated
5. Unused receptacle ports are fitted with UW port plugs
Connections may be periodically inspected and maintained with O-ring grease, at a
minimum before each buoy deployment.
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CB-Series data buoys contain a waterproof data well constructed of stainless steel where
batteries are mounted. Whenever installing or maintaining battery systems, use caution to
avoid short-circuiting of battery poles to the metal walls of the data well. Gloves and tools
with rubber grips are recommended, and any exposed connections should always be
covered with electrical tape or other suitable coverings.
Safe deployment
Above all else, safety is the most critical consideration to take during the planning and
precautions of a buoy deployment. Any time a buoy system is deployed, there are
countless hazards, including, but not limited to, working on/near water and lifting of heavy
equipment. Important factors to consider for personnel safety are:
Use of safety equipment (i.e., life jackets, gloves, steel toed boots, etc.,)
Proper lifting and mooring techniques
Awareness of on-site and surrounding weather conditions and advisories
Despite careful planning and precautions, unforeseen situations are always still a
possibility. Buoy deployments are an at-risk operation, and the user assumes liability for
any injury or damages that may occur.
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2. Buoy Assembly
Using NexSens Electronics in CB-Series Data Buoys
Although users may provide their own electronics, including data loggers, modems, and
batteries, many CB-Series data buoys are delivered as complete, plug-and-play system
packages with a NexSens data logger as the central component of the system.
Data Loggers
NexSens offers four different data logging systems for buoy deployment, all of which are
based on the central processing unit of the X2 environmental data logger:
1. X2-SDL Submersible Data Logger – fully submersible unit designed for standalone
operation or installed in the CB-50 platform
2. X2-SDLMC Submersible Data Logger – fully submersible unit with topside wet-mate
sensor connectors for standalone operation or installed in the CB-25 platform
3. X2-CB Buoy-Mounted Data Logger – waterproof, lid-mounted package for
integration on CB-Series data buoys with data well and solar charging (model CB-150
and larger)
4. X2-CBMC Buoy-Mounted Data Logger – lid-mounted package with wet-mate
connectors for use on CB-Series data buoys in challenging environments such as
offshore, typical on model CB-650 and larger
Reference the Data Loggers section of the NexSens Knowledge Base for resources
including Quick Start and User Guides to install, configure and operate NexSens data logger
electronics with CB-Series data buoys. Data logger user guides include detailed instructions
on interfacing with sensors and setting up transmission of data to the WQData LIVE web
datacenter.
Figure 1: X2-SDL data
logger
Figure 2: X2-SDLMC
data logger
Figure 3: X2-CB data
logger
Figure 4: X2-CBMC
data logger
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Battery Packs
X2-SDL and X2-SDLMC data loggers rely on internal batteries to supply power. X2-CB and
X2-CBMC data loggers are designed for use on CB-Series data buoys with solar charging
(model CB-150 and larger). These buoys have a data well for installation of battery packs,
and the data logger serves as the top plate to provide a waterproof seal on the data well.
NexSens offers two standard types of battery harnesses, which include sealed lead acid
(SLA) batteries, solar regulator, mounting bracket and data logger connection cable pigtail
(UW-6 connector):
1. CB-A01-2 – contains two 8.5 A-hr batteries (CB-150 only)
2. CB-A05-x – contains one to four 28 A-Hr batteries (depending on buoy capacity – see
table below)
The following table shows what battery harness models each CB-Series data buoy model
has capacity for in the data well. However, what model is selected should be based on a
complete power budget analysis that includes system power demand, solar charge
capacity (panel size) and available sunlight based on deployment location to aid in
determining how much reserve battery power is needed.
See CB-Series Buoy Battery Capacities for additional relevant specifications and capacity
information for the battery harnesses.
CB-A01-2 CB-A05-1 CB-A05-2 CB-A05-3 CB-A05-4
CB-150 x x
CB-250 x x x
CB-450 x x x
CB-650 x x x
CB-950 x x x
CB-1250 x x x x
NexSens battery harnesses are typically shipped pre-installed in CB-Series data buoys.
However, in cases where batteries need to be installed or replaced, detailed instructions
can be found here.
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Accessories
Many optional accessories are available for CB-Series data buoys with NexSens electronics.
In some cases, certain accessories are strongly recommended, such as the addition of
sacrificial zinc anodes for use in saltwater. The table below lists the most common
accessories with explanation of when each should be used.
In addition to accessories, a list of available top-side and subsurface sensor mounts is
available here.
Part (link) Description Use Cases
M550-
F-Y
Solar marine light with flange mount
& 1-3 nautical mile range, 15 flashes
per minute, yellow
For nighttime visibility on CB-150,
CB-250 and CB-450 buoys
M650H-
Y
Solar marine light with 4 nautical
mile range, 15 flashes per minute,
yellow
For nighttime visibility on CB-650,
CB-950 and CB-1250 buoys
CB-RR Radar reflector for CB-Series data
buoys
For visibility on ship radar screens,
mounts to CB-650, CB-950 and CB-
1250 buoys
CB-CCA Cage anti-rotation collar for CB-
Series data buoys
For strengthening connection of
instrument cage on CB-150, CB-250
and CB-450 buoys (included with CB-
650 and larger)
CB-ZA Sacrificial zinc anode for CB-Series
data buoys
For protection of stainless steel
frame when used in saltwater,
recommended two per buoy, requires
periodic replacement
CB-PW-
AC-
30W
Battery float charger for CB-A01-2
battery harness, UW 6-pin plug to AC
adapter, 30W
For charging CB-A01-2 battery pack
without opening the buoy data well
CB-PW-
AC-
60W
Battery float charger for CB-A05-X
battery harness, UW 6-pin plug to AC
adapter, 60W
For charging CB-A05-X battery pack
without opening the buoy data well
BALxx Ballast weight for CB-Series data
buoys, 25 – 150 lb. (11.3 – 68 kg)
For adding counter-ballast to buoys,
see recommended ballast weights by
buoy model
91xM
Deployment pipe assembly with stop
bolt & threaded male adapter,
schedule 80 PVC, 32″ length
For secure, near-surface instrument
deployment with topside access for
maintenance
Creating a Parts List
To obtain a complete parts list including recommended accessories and pricing for a CB-
Series system based on the above components, fill out and submit the NexSens Buoy
Configurator form.
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Custom Data Buoy Configuration Guide
While many NexSens data buoys are delivered as turnkey systems featuring a NexSens X2-
CB or X2-CBMC buoy-mounted data logger, they are also designed to support custom
integration of user-supplied, third-party electronics. The CB-Series data buoys from the CB-
150 and larger are designed with an open data well in the center of the hull to facilitate
such deployments.
The aim of this guide is to describe the options and design process for configuring a custom
system using the CB-Series data buoy platforms. The topics considered are (click to jump to
a section):
Selecting a buoy platform
Buoyancy requirements
Power requirements
Data well size requirements
Sensor mount requirements
Selecting a data well lid
Selecting accessories
Creating a parts list
Selecting a Buoy Platform
The first step in designing a custom buoy system is to choose a buoy platform. The CB-
Series data buoys range in size from the small and portable CB-150 with 150 lb (68 kg) net
buoyancy and 24” (61 cm) hull diameter to the large and powerful CB-1250 with 1250 lb
(567 kg) net buoyancy and 48” (122 cm) hull diameter. An overview of the complete line of
buoys is available in the CB-Series comparison chart.
Buoyancy, power supply, physical space in the watertight data well for mounting user-
Figure 1: From left to right, CB-150, CB-250, CB-450, CB-650, CB-
950 and CB-1250 data buoys.
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supplied electronics, and mounting options for specific sensor types are the main criteria
used to determine which platform is best suited for a particular application. These factors
are discussed in more detail in the following sections.
Buoyancy Requirements
Determining minimum required buoyancy is a fairly straightforward process. Calculate the
total in-water weight of the sensor payload and mooring hardware to be used. Compare this
to the net buoyancy of the platform(s) under consideration, keeping in mind that the value
listed in the datasheet is the absolute maximum the buoy can safely handle. Allowing a
minimum 25% margin is recommended. Remember to account for potential changes during
the deployment of the buoy system, such as weight added due to biological growth on the
buoy hull, frame and mooring system.
In many cases, a weight to net buoyancy calculation is not the only buoyancy-related
consideration. Any deployment location subject to substantial waves, currents and/or
periodic rough conditions may be hazardous for smaller platforms. Although watertight,
buoys should not be submerged for best performance. A factor of 100% surplus
buoyancy or more may be desirable.
For more information on buoy buoyancy and stability, see CB-Series Data Buoy Ballast
Weight & Stability.
Power Requirements
Power supply is the second primary factor that drives buoy selection, and very often the
controlling factor. The size of solar panels varies by buoy model, as does the height of the
data well where battery packs are mounted. Proper sizing of a power system requires
calculation of the combined demand of the data logger, sensors and other electrical
components of the system and determination of the estimated solar insolation at the
geographic location where the buoy will be deployed.
To aid with system power analysis, NexSens has developed a power budget calculator that
factors in the system variables and allows for custom inputs. This tool is available from
Figure 2: Buoy hull X-ray
view showing data well with
battery harness, data well
lid, and instrument pass-
through holes.
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NexSens upon request.
Battery packs are available from NexSens or can be user-supplied. NexSens CB-A01-2 and
CB-A05-X battery harnesses include a solar regulator, sealed lead acid (SLA) batteries, and
mounting bracket for secure installation in the buoy data well. The compatible battery
harnesses by buoy model are as follows:
CB-A01-2 CB-A05-1 CB-A05-2 CB-A05-3 CB-A05-4
CB-150 x x
CB-250 x x x
CB-450 x x x
CB-650 x x x
CB-950 x x x
CB-1250 x x x x
For additional relevant specifications and capacity information for the battery harnesses,
see CB-Series Buoy Battery Capacities.
For user-supplied battery packs, there are two threaded hubs in the bottom of the data well
spaced 7-¾” (19.7 cm) apart (note minor variation may be possible due to welding
process). These allow connection of 3/8″-16 threaded rod which can be locally sourced or
supplied by NexSens (part number N11149). A predesigned bracket like what is used in the
CB-Series battery harnesses can optionally be supplied as well (part number CB0468).
Aside from the threaded hubs, there are no built-in connection points inside of the data
Figure 3: Data well internal
view with optional battery
mount hardware pictured.
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well. However, wedge-shaped and round foam inserts sized for the data well can also be
provided to help secure mounted electronics and prevent items from moving inside the
data well. Part numbers are:
CB0161 – wedge-shaped for packing batteries and other sqaure-shaped items
CB0162 – round with small center hole cutout
CB0163 – round with large center hole cutout
Warning! The data well is constructed entirely of 316 stainless steel. Use
extreme caution when installing or replacing any batteries in the data well. Any
contact between the walls of the data well and battery poles can cause short-
circuiting. This includes through metallic tools used to tighten connections.
Always use tools with rubber grips when handling batteries.
Data Well Size Requirements
Adequate physical space in the data well is necessary for placing any electronics that must
be kept free from moisture. All CB-Series data buoys have the same data well inner
diameter of 10.3” (26.2 cm). The height of the data well varies based on buoy model:
Model Data Well Height
(in)
Data Well Height
(cm)
CB-150 13.5″ 34.2 cm
CB-250 19.5″ 49.5 cm
CB-450 19.5″ 49.5 cm
CB-650 21.5″ 54.6 cm
CB-950 25.5″ 64.8 cm
CB-1250 27.5″ 69.9 cm
The drawing sets in the Knowledge Base show how much space remains in the data well of
each buoy model with a battery harness installed. The below examples show a cutaway
view of the data well of the CB-150 with CB-A01-2 and CB-A05-1 battery harnesses,
respectively. The given dimension is in inches.
Figure 4: CB-150 with CB-
A01-2 Battery Harness.
Figure 5: CB-150 with CB-
A05-1 Battery Harness.
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Sensor Mount Requirements
Both standard and sensor-specific mounting hardware is available for the CB-Series data
buoys.
A common feature of all buoy hulls is a set of three pass-through holes for routing
instrument cables from the data well to below the water surface while keeping them well
protected. The pass-through holes vary from 2” on the CB-150 and CB-250 to 8” on the CB-
1250.
Model Pass-Through Hole
Diameter (in)
Pass-Through Hole
Diameter (cm)
CB-150 2.0″ 5.1 cm
CB-250 2.0″ 5.1 cm
CB-450 4.0″ 10.2 cm
CB-650 4.0″ 10.2 cm
CB-950 6.0″ 15.2 cm
CB-1250 8.0″ 20.3 cm
Optional 91xM deployment pipes can thread directly into the bottom of the pass-through
ports to provide for secure placement of sensors with topside access for maintenance
without having to remove the buoy from the water. This is sometimes a preferred solution
compared to fixing sensors onto the instrument cage below the buoy. In such cases, the
pass-through port size may be a determining factor for buoy selection. For example,
although the CB-250 and CB-450 models provide the exact same power capacity, the CB-
450 with its 4” pass-through ports would be a better option to deploy a water quality sonde
with 4” diameter.
Some mounting hardware is designed for a specific buoy model. For example, the Nortek
Aquadopp ADCP Buoy Mount fits only into the 6” pass-through port of the CB-950 or the
12” pass-through port of the CB-1250.
Figure 6: CB-450 view
showing 4″ pass-through
holes.
Figure 7: CB-450 with 914M instrument
deployment pipe.
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A list of top-side and subsurface sensor mounting accessories is available here.
In the design process, consider what instruments will be mounted onto the buoy and how
well-suited the selected buoy is for accommodating them.
Selecting a Data Well Lid
Once the buoy platform is selected, the data well lid is the next component to determine.
There are four alternatives for data well lid. The selection criteria are given below, and the
standard and optional parts are listed for each lid type. Those marked with a ¹ are included
standard with the respective lid, and those marked with ² are options that must be ordered
separately.
1. The CB-PTL Pass Through Lid is the simplest and most common lid type for
deployments in freshwater and some marine environments where full buoy submersion
is not a high risk. It features gland fittings for passing through cables with bare leads,
which are tightened around the cable jacket to create a seal. For pluggable
connections, sensor and RF bulkhead adapters are available. Contents and options:
a. UW6-BULK Power Bulkhead Cable Assembly¹
b. Standard pressure release valve¹
c. (6) sensor port openings
i. Set of (6) sensor port plugs¹ (for unused ports)
ii. Set of (6) gland fittings¹
d. Spare O-rings and grease¹
e. RF-BULK RF Bulkhead Connector Assembly²
f. UW-BULK Sensor Bulkhead Connector Assembly² (requires UW-CON
connectorization of sensor cable)
g. SA1352 CB-Series battery harness cable adapter² (connects UW6-BULK to a CB-
A01-2/CB-A05-X battery harness)
Figure 8: CB-PTL with
all standard parts
included.
Figure 9: RF-BULK RF
Bulkhead Connector
Assembly.
Figure 10: UW-BULK
Sensor Bulkhead
Connector Assembly.
Figure 11: SA1352
Battery harness
connector assembly.
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2. The CB-MCL wet-mate Marine Connector Lid incorporates all marine-grade wet-
mate connectors and a 5 psi UW-PRV Pressure Relief Valve. It is ideal for harsher
marine environments where occasional full buoy submersion is a concern. Contents
and options:
a. CB-MCL Solar Connector with UW6 Solar/COM port adapter¹
b. UW-PRV Pressure Release Valve¹
c. Bushing connector¹
i. Can optionally be replaced with RF-BULK RF Bulkhead Connector Assembly²
d. (5) sensor port openings
i. (5) MCBH Connector Port Plugs¹ (for unused ports)
ii. MCBH Male Bulkhead Connectors² (4-pin, 5-pin, 6-pin or 8-pin, use with MCDC
Female Dummy Plugs²)
iii. MCBH Female Bulkhead Connectors² (4-pin, 5-pin, 6-pin or 8-pin, use with
MCDC Male Dummy Plugs²)
3. SA1304 blank plates are available for users who want to start with a blank plate and
drill their own holes.
a. SA1304-C1: Custom plate with bolt holes and power/vent only (UW6-BULK Power
Bulkhead Cable Assembly¹)
b. SA1304-C2: Custom plate with bolt holes only
4. No lid provided. User can machine own plate using dimensional drawing with bolt hole
locations provided by NexSens.
Figure 12: CB-MCL
with all standard parts
included.
Figure 13: RF-BULK RF
Bulkhead Connector
Assembly.
Figure 14: MCBH Male
Wet-Mate Bulkhead
Connectors.
Figure 15: MCBH
Female Wet-Mate
Bulkhead Connectors.
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