Template: 3101-00074, Ver 1-01

Revision HistoryVersion Description Originator ECR No. Release Date0-00 Initial Draft

0-01 Updates and edits R. Weller

0-02 Checked specifications, revised R. Weller

0-03 Separate fast response hygrometer as separate specification.

R. Weller

1-00 Initial release R. Weller 1303-00378 13 July 2011

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Signature Page

This document has been reviewed and approved for release.

OOI Senior Systems Engineer:

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Table of Contents1.0 General......................................................................................................................................1

1.1 Ocean Observatories Initiative (OOI) Overview...................................................................11.2 Document Scope and Purpose.............................................................................................11.3 Documents............................................................................................................................2

1.3.1 Informational................................................................................................................21.3.2 Applicable....................................................................................................................3

1.4 Definitions.............................................................................................................................31.4.1 Glossary and Acronyms...............................................................................................31.4.2 Conventions.................................................................................................................4

2.0 Specifications...........................................................................................................................52.1 Measurement........................................................................................................................5

2.1.1 Turbulent wind velocity, each of 3-components...........................................................52.1.2 Turbulent Air Temperature...........................................................................................62.1.3 Relative humidity.........................................................................................................62.1.4 Barometric pressure....................................................................................................72.1.5 Three-axis Linear and Angular Platform motion..........................................................8

2.2 Operational...........................................................................................................................92.2.1 Operational Depth Range............................................................................................92.2.2 Environmental..............................................................................................................92.2.3 Service Requirements.................................................................................................92.2.4 Calibration Requirements............................................................................................92.2.5 Deployment Interval...................................................................................................102.2.6 Duty cycle..................................................................................................................10

2.3 Mechanical/Physical...........................................................................................................102.3.1 Materials....................................................................................................................102.3.2 Size............................................................................................................................102.3.3 Weight........................................................................................................................10

2.4 Electrical.............................................................................................................................102.4.1 Interference Requirements........................................................................................102.4.2 Voltage.......................................................................................................................102.4.3 Current.......................................................................................................................102.4.4 Power.........................................................................................................................102.4.5 Grounding..................................................................................................................102.4.6 Battery Life.................................................................................................................102.4.7 Modes/State of Operation..........................................................................................112.4.8 Isolation.....................................................................................................................112.4.9 Interface to hygrometer..............................................................................................11

2.5 Data Storage and Processing.............................................................................................112.5.1 Storage Capacity.......................................................................................................112.5.2 Data Averaging..........................................................................................................11

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2.5.3 Onboard Data Processing.........................................................................................112.5.4 Post-recovery Data Processing.................................................................................11

2.6 Software/Firmware..............................................................................................................112.7 Platform Interfaces..............................................................................................................12

2.7.1 Mechanical.................................................................................................................122.7.2 Electrical....................................................................................................................122.7.3 Data and Communication..........................................................................................12

2.8 Compliance.........................................................................................................................132.9 Safety..................................................................................................................................132.10 Shipping and Storage.........................................................................................................13

2.10.1 Shipping.....................................................................................................................132.10.2 Storage......................................................................................................................132.10.3 Safe Handling............................................................................................................14

2.11 Identification........................................................................................................................142.11.1 Physical Markings......................................................................................................14

2.12 Quality.................................................................................................................................142.12.1 Product Quality..........................................................................................................14

3.0 Documentation and Support.................................................................................................144.0 Appendices.............................................................................................................................15

4.1 Preferred OOI Standard Connector types..........................................................................15

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1.0 General

1.1 Ocean Observatories Initiative (OOI) Overview

Although the ocean is central to the habitability of our planet, it is largely unexplored. Biological, chemical, physical, and geological processes interact in complex ways in the ocean, at the seafloor, and at the air-sea interface. Our ability to learn more about these processes is severely limited by technical infrastructure, and developing a more fundamental scientific understanding of these relationships requires new and transformational approaches to ocean observation and experimentation.

The Ocean Observatories Initiative (OOI) will lay the foundation for future ocean science observations. OOI will enable powerful new scientific approaches by transforming the community’s focus from expedition-based data gathering to persistent, controllable observations from a suite of interconnected sensors. The OOI's networked sensor grid will collect ocean and seafloor data at high sampling rates over years to decades. Researchers will make simultaneous, interdisciplinary measurements to investigate a spectrum of phenomena including episodic, short-lived events (tectonic, volcanic, oceanographic, biological, and meteorological), and more subtle, longer-term changes and emergent phenomena in ocean systems (circulation patterns, climate change, ocean acidity, and ecosystem trends).

The OOI will enable multiple scales of marine observations that are integrated into one observing system via common design elements and an overarching, interactive cyberinfrastructure. Coastal-scale assets of the OOI will expand existing observations off both U.S. coasts, creating focused, configurable observing regions. Regional cabled observing platforms will ‘wire’ a single region in the Northeast Pacific Ocean with a high speed optical and high power grid. Global components address planetary-scale changes via moored open-ocean buoys linked to shore via satellite. Through a unifying cyberinfrastructure, researchers will control sampling strategies of experiments deployed on one part of the system in response to remote detection of events by other parts of the system.

A more detailed discussion of the Oceans Observatories Initiative can be found in the OOI Final Network Design.

1.2 Document Scope and Purpose

The purpose of this specification is to provide the requirements for a direct covariance flux instrument package to be purchased for use on the Coastal and Global Scale Nodes (CGSN) of the Ocean Observatories Initiative. Direct covariance flux instrument packages will be mounted on surface buoys that will be deployed in both coastal regions (depths up to ~600 m) and open ocean regions (at latitudes above 40 degrees). Coastal and Global buoys will include a tower for mounting sensors at a height of ~3-5 m above water level. Buoys will be designed to orient themselves relative to the wind.

This document describes the physical, functional and electrical characteristics of direct covariance flux instrument packages required by CGSN.

Direct covariance flux systems (DCFS) measure the vertical fluxes associated with eddies in the flow over the ocean. When done well, they provide a direct measure of vertical transports or fluxes. The bulk meteorological system provides a second way to measure the air-sea fluxes, but the bulk method relies on parameterizations. These parameterizations and hence the accuracy of the bulk methods are not well known in high winds (>20 m s-1) and energetic and/or changing

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surface wave conditions. Thus, the OOI requires a DCFS instrument package to ensure the requirements to observe the air-sea fluxes are met in high wind and sea state conditions.

At the heart of a DCFS is the ability to measure the fluctuating or turbulent components of the wind (u’, v’, and w’ which are respectively the turbulent east, turbulent north, and turbulent vertical wind velocity components) and the desired fluctuating scalar quantity (e.g. T’, q’, CO2’, where these are temperature, specific humidity and CO2 fluctuations, respectively). The challenge for a buoy-mounted DCFS system is that it measure wind in the moving reference frame of the buoy, so the buoy DCFS must correct relative turbulent wind for the rotation and translation of the buoy. The measurements of the turbulent components and the corrections are done at a rate of about 10 to 20 Hz.

A buoy-based eddy covariance flux system thus consists of a 3-axis sonic anemometer logging fast wind components (u,v,w) and sonic temperature (Ts) at 10 to 20 Hz plus a fast hygrometer (also 10 to 20 Hz). A fast platform motion-measuring system is required to remove wave-induced motions and rotate the wind components into a fixed-earth coordinate system. The motion system must measure 3-axis linear accelerations and 3-axis angular rates with software to integrate these to 3-axis linear motions and pitch, roll, and heading angles. Motion corrections must be done to the raw sonic time series. A typical fast hygrometer uses nod-dispersive IR (NDIR) absorption along an optical path of 10-20 cm. Contamination of the optics by sea spray and other sources (e.g., birds) may rapidly degrade performance. The fluxes are obtained by cross-correlating the true vertical velocity with the true horizontal wind components, fast temperature, and fast humidity. Additional variables (mean air temperature, humidity, and pressure) may be required to interpret/correct the fluxes.

Because fast response hygrometers are also used in land-based direct covariance flux systems, there are commercial sources for these instruments addressing a marketplace much larger than that of buoy and ship-based DCFS systems. Continued evolution and improvement is anticipated in fast response hygrometers, so the approach taken in developing an OOI specification of a DCFS is to specify a buoy-based system with sonic anemometer, motion measurement and correction, and ancillary mean sensors for humidity, temperature, and pressure that is plug-and-play compatible with commercially available fast response hygrometers. The acquisition of the fast response hygrometer from a commercial source also allows for specifying the calibration, refurbishment, repair, and upgrades services to be needed by the OOI to be part of the acquisition of the fast response hygrometer, removing the significant burden of supporting the least robust component of the DCFS system from the OOI DCFS supplier. This is important because the market for buoy and ship DCFS systems is small, and potential respondents to an RFP for a buoy-based DCFS may not have their own capability to support and service the fast response hygrometer.

1.3 Documents

1.3.1 InformationalThe documents listed in this section are for informational purposes only and may not have been referenced in this specification.

Consortium for Ocean Leadership, Inc. 2010. Final Network Design. Washington, DC. [Online] Available: http://www.oceanleadership.org/programs-and-partnerships/ocean-observing/ooi/network-design/

Burba, G. and D. Anderson (2010) A Brief Practical Guide to Eddy Covariance Flux Measurements: Principles and Workflow Examples for Scientific and Industrial Applications. www.licor.com. 213 pp.

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Campbell Scientific, Inc. (1998) Instruction Manual: Eddy Covariance System CA27 and KH20, www.campbellsci.com.

Edson, J. B., A. A. Hinton, K. E. Prada, J. E. Hare, and C.W. Fairall (1998) Direct Covariance Flux Estimates from Mobile Platforms at Sea. Journal of Atmospheric and Oceanic Technology, 15, 547-562.

Frederickson, P. A., K. L. Davidson, F. K. Jones, and T. Neta, (2001) Naval Postgraduate School FLUX Buoy Data Report for the MUSE Deployment, August-September 2000, Monterey Bay, California. Technical Report, Naval Postgraduate School, 19 pp.

Gill, G. C. (1976) Development and testing of a no-moving parts static pressure inlet for use on ocean buoys. NOAA Data Buoy Office Progress Rep. 01-6-038-115, 43 pp.

Launiainen, S., J, Rinne, J. Pumpanen, L. Kulmala, P. Kaori, P. Keronen, E. Silviola, T. Pohja, P. Hari, and T. Vesala (2005) Eddy covariance measurements of CO2 and sensible and latent heat fluxes during a full year in a boreal pine forest trunk-space. Boreal Environment Research, 10, 569-588.

1.3.2 ApplicableN/A

1.4 Definitions

1.4.1 Glossary and Acronyms Accuracy – Closeness of the agreement between the result of a measurement and the

value of the measurand (or true value of the measurement). (Taylor and Kuyatt, 1994)

Burst Sampling – Intermittent rapid sampling at or near the maximum sampling rate for short intervals between longer quiescent periods.

CGSN – Coastal and Global Scale Nodes

DCFS – Direct Covariance Flux System

EIA – Electronics Industries Association

Instrument – A device that contains one or more sensors and a method for converting the information from the sensor into a transmittable and storable form.

Objective Value – The desired value of a technical parameter. This value, if provided, may be more challenging to achieve than the Threshold value. It is a goal, not a requirement, for the instrument.

OOI – Ocean Observatories Initiative

Operate – Correctly performing designed functionality.

Precision – The closeness of agreement between independent measurements obtained under stipulated conditions of repeatability, generally expressed as a standard deviation (or standard uncertainty) of measurement results (Taylor and Kuyatt, 1994). Used as a measure of stability of an instrument/sensor and its capability of producing the same measurement over and over again for the same input signal.

Resolution – The smallest amount of input signal change that the instrument/sensor can detect reliably.

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Response Time – The time required for an output to reach a specified fraction of its final value as a result of a step change in input.

PSS – Practical Salinity Scale, the UNESCO Practical Salinity Scale of 1978 (PSS78) defines salinity as a dimensionless conductivity ratio.

RMS – Root Mean Square

Sensor – A device that will convert a physical phenomenon into an electrical signal that can in turn be digitized through the use of an analog to digital converter. A sensor is normally housed in an instrument. Data coming from sensors is normally raw and needs to be calibrated.

Survive – Experience an event without major loss of hardware. System may experience loss of functionality requiring repair to return to normal mode functionality. An example of this is knockdown of a global mooring or loss of some part of the mooring resulting in the instrument descending to the bottom. Any internal memory in the instrument shall remain accessible, but the sensors may need to be replaced to return to normal functionality.

Sustain – Experience an event (environmental extreme or condition) without permanent loss of normal mode functionality. System may experience reduction of functionality during event.

Threshold Value – The minimal limiting acceptable performance value that this item must meet of a technical parameter. If this item does not meet the performance as specified by the threshold value it may not be sufficient for inclusion in the OOI system.

1.4.2 ConventionsAll values contained in this document are Threshold Values unless specifically stated otherwise.

Specification items are assigned unique identification numbers specific to this document. Items tied directly to requirements maintained in the OOI requirements database are followed by the requirement number in brackets (e.g., [L4-CG-IP-RQ-XXX]). The requirement number is intended for internal OOI use only.

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2.0 Specifications

2.1 Measurement

Values provided are threshold unless otherwise stated.

2.1.1 Turbulent wind velocity, each of 3-components. Wind speed is the square root of the sum of the squares of the three components. The individual components can be negative or positive while the speed/velocity is positive by definition.

a) Measurement with unit(s) Turbulent wind velocity, 3 component (speed in m/s, direction in degrees)

b) Minimum Value TVEL-001 Turbulent wind velocity instruments shall measure wind speed to a

minimum value of 0 m/s. [L4-CG-IP-RQ-339] TVEL-002 Turbulent wind velocity instruments shall measure wind direction to a

minimum value of 0° [L4-CG-IP-RQ-630]c) Maximum Value

TVEL-003 Turbulent wind velocity instruments shall measure wind speed to a maximum value of 65 m/s. [L4-CG-IP-RQ-339]

TVEL-004 Turbulent wind velocity shall measure wind direction to a maximum value of 360° [L4-CG-IP-RQ-360]

d) AccuracyTVEL-005 Turbulent wind velocity instruments shall have a wind speed accuracy of

better than +/- 0.18 m/s at speeds of 12 m/s or less, and 1.5% RMS at speeds greater than 12 m/s. [L4-CG-IP-RQ-334]

TVEL-006 Turbulent wind velocity instruments shall have a wind direction accuracy of 2° [L4-CG-IP-RQ-335]

e) PrecisionN/A

f) ResolutionTVEL-007 Turbulent wind velocity instruments shall have a wind speed resolution of

0.01 m/s. [L4-CG-IP-RQ-337]TVEL-008 Turbulent wind velocity instruments shall have a wind direction resolution

of 0.1°. [L4-CG-IP-RQ-338]g) Drift

TVEL-009 Turbulent wind velocity instruments shall have an annual wind speed drift of less than 0.01 m s-1 per year. [L4-CG-IP-RQ-340]

h) Response TimesN/A

i) Sampling FrequencyTVEL-010 Turbulent wind instruments shall be capable of sampling at rates of 1 Hz

to 20 Hz, inclusive. [L4-CG-IP-RQ-341]

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j) Constraints/DependenciesTVEL-011 Turbulent wind instruments should provide ASCII digital output [RS 232,

RS422, RS485] at baud rates between 4,800 and 57,600. This is an objective.

TVEL-012 Turbulent wind instruments should operate at temperatures between -40°C to 70°C. This is an objective.

TVEL-013 Turbulent wind instruments should operation at humidities between 5 and 100%. This is an objective.

2.1.2 Turbulent Air Temperaturea) Measurement with unit(s)

Turbulent air temperature (temperature in °C)b) Minimum Value

TEMP-001 Turbulent air temperature instruments shall measure temperature to a minimum value of -30° C. [L4-CG-IP-RQ-636]

c) Maximum ValueTEMP-002 Turbulent air temperature instruments shall measure temperature to a

maximum value of 45° C. [L4-CG-IP-RQ-636] d) Accuracy

TEMP-003 Turbulent air temperature instruments shall measure temperature with an accuracy of 1° C. [L4-CG-IP-RQ-634]

e) PrecisionN/A

f) ResolutionTEMP-004 Turbulent air temperature instruments shall measure temperature with a

resolution of 0.01° C. [L4-CG-IP-RQ-635]g) Drift

N/Ah) Response Times

N/Ai) Sampling Frequency

TVEL-005 Turbulent air temperature instruments shall be capable of sampling rates of 1 Hz to 20 Hz, inclusive. [L4-CG-IP-RQ-637]

j) DependenciesN/A

2.1.3 Relative humiditya) Measurement with units(s)

Relative Humidity (percentage)b) Minimum Value

RHUM-001 Relative Humidity instruments shall measure humidity to a minimum value of 0%. [L4-CG-IP-RQ-79]

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c) Maximum ValueRHUM-002 Relative Humidity instruments shall measure humidity to a maximum

value of 110%. [L4-CG-IP-RQ-79]d) Accuracy

RHUM-003 Relative Humidity instruments shall have a laboratory accuracy of +/- 2%. [L4-CG-IP-RQ-74]

RHUM-004 Relative Humidity instruments should have a field accuracy of +/- 5%. This is an objective.

e) PrecisionN/A

f) ResolutionRHUM-005 Relative Humidity instruments shall have a resolution of 0.1%. [L4-CG-

IP-RQ-75]g) Drift

RHUM-006 Relative humidity instruments shall have an annual drift of less than 5.0%. [L4-CG-IP-RQ-318]

h) Response TimesN/A

i) Sampling FrequencyRHUM-007 Relative Humidity measurements shall be made at a frequency of once

per minute. If higher frequency measurements are possible, they shall be boxcar averaged to provide average measurements once per minute. [L4-CG-IP-RQ-78]

j) DependenciesRHUM-008 Relative humidity sensors will be located in close proximity (within 10

cm) to the turbulent wind sensor to support calculation of the virtual temperature from the sonic temperature.

k) Sea Spray ResistanceRHUM-009 Relative Humidity instrument performance shall not be affected by sea

spray. [L4-CG-IP-RQ-80]

2.1.4 Barometric pressure a) Measurement with units(s)

Barometric Pressure (millibars) b) Minimum Value

BARO-001 Barometric Pressure instruments shall measure pressure to a minimum value of 850 millibars. [L4-CG-IP-RQ-71]

c) Maximum ValueBARO-002 Barometric Pressure instruments shall measure pressure to a maximum

value of 1050 millibars. [L4-CG-IP-RQ-71]d) Accuracy

BARO-003 Barometric pressure instruments shall have a laboratory accuracy of +/-0.2 millibars. [L4-CG-IP-RQ-66]

BARO-004 Barometric pressure instruments should have a field accuracy of +/-0.5 millibars. This is an objective.

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e) PrecisionN/A

f) ResolutionBARO-005 Barometric pressure instruments shall have a resolution of 0.1 millibars.

[L4-CG-IP-RQ-67]g) Drift

BARO-006 Barometric pressure instruments shall have an annual drift of less than 0.5 millibars. [L4-CG-IP-RQ-317]

h) Response TimesN/A

i) Sampling FrequencyBARO-007 Barometric Pressure measurements shall be made at a frequency of

once per minute. If higher frequency measurements are possible, they shall be boxcar averaged to provide average measurements once per minute. [L4-CG-IP-RQ-70]

j) DependenciesBARO-008 The input port of the Barometric Pressure sensor shall be fitted with a

Gill pressure port (Gill, 1976). [L4-CG-IP-RQ-72]

2.1.5 Three-axis Linear and Angular Platform motiona) Measurement with units(s)

Linear and angular platform motion (m/s, deg/s); Angular position (degrees)b) Minimum Value

MOTN-001 Linear motion sensors shall measure motion to a minimum value of -15 m/s [L4-CG-IP-RQ-650]

MOTN-002 Angular motion sensors shall measure motion to a minimum value of -60 deg/s. [L4-CG-IP-RQ-651]

MOTN-003 Angular position sensors shall measure position to a minimum value of 0 degrees. [L4-CG-IP-RQ-652]

c) Maximum ValueMOTN-004 Linear motion sensors shall measure motion to a maximum value of 15

m/s [L4-CG-IP-RQ-650]MOTN-005 Angular motion sensors shall measure motion to a maximum value of 60

deg/s. [L4-CG-IP-RQ-651]MOTN-006 Angular position sensors shall measure position to a maximum value of

360 degrees. [L4-CG-IP-RQ-652]d) Accuracy

MOTN-007 Linear motion sensors shall have an accuracy of 0.04 m/s. [L4-CG-IP-RQ-644]

MOTN-008 Angular motion sensors shall have an accuracy of 0.5 deg/s. [L4-CG-IP-RQ-645]

MOTN-009 Angular position sensors shall have an absolute accuracy of 0.5 degrees. [L4-CG-IP-RQ-646]

e) PrecisionN/A

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f) ResolutionMOTN-010 Linear motion sensors shall have a resolution of 0.01 m/s. [L4-CG-IP-

RQ-647]MOTN-011 Angular motion sensors shall have a resolution of 0.004 deg/s. [L4-CG-

IP-RQ-648]MOTN-012 Angular position sensors shall have a resolution of 0.05 degrees or

better. [L4-CG-IP-RQ-649]g) Drift

MOTN-013 Platform motion instruments shall have an angle random walk of 0.25 degrees/hr (15 degrees per hour per Hz) or better. [L4-CG-IP-RQ-653]

h) Response TimesN/A

i) Sampling FrequencyMOTN-014 Platform motion instruments shall be capable of sampling rates of 1 Hz

to 20 Hz, inclusive. [L4-CG-IP-RQ-654]j) Dependencies

MOTN-015 Package motion will be measured close (<1 m) to the location of the turbulent wind velocity sensor.

2.2 Operational

2.2.1 Operational Depth RangeN/A

2.2.2 Environmentala) Salinity

N/Ab) Temperature

OPER-001 Instruments shall be capable of making air-sea measurements within an ambient air temperature range of -30° C and +45° C. [L4-CG-IP-RQ-432]

c) BiofoulingOPER-002 Sensors shall utilize bio-fouling mitigation to enable nominal operations

over the defined maintenance interval. [L4-CG-IP-RQ-446]d) Icing

OPER-003 Instruments mounted in air shall sustain periods of icing. [L4-CG-IP-RQ-405]

2.2.3 Service RequirementsN/A

2.2.4 Calibration Requirements OPER-004 Sensors should maintain their calibration over the required deployment

intervals. This is an objective. [L4-CG-IP-RQ-286]

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2.2.5 Deployment IntervalOPER-005 The designed deployment interval for instrument packages on moored

assets shall be 13 months. [L3-CG-RQ-168; L3-CG-RQ-496; L3-CG-RQ-497]

2.2.6 Duty cycleOPER-006 The Direct Covariance Flux System shall be capable of being duty cycled.

For example, operating for a period of minutes (0 to 20) every hour as needed to achieve average power consumption over one hour of less than 10 Watts. [L4-CG-IP-RQ-658]

2.3 Mechanical/Physical

2.3.1 Materials MECH-001 Instrument electronics housings shall be designed to be corrosion

resistant. [L4-CG-IP-RQ-288]MECH-002 The instrument package and components mounted on surface buoys

shall be capable of surviving immersion in seawater to a depth of 5 m. [L3-CG-RQ-886]

2.3.2 SizeN/A

2.3.3 WeightN/A

2.4 Electrical

2.4.1 Interference RequirementsELEC-001 A/D converters shall be placed as close to the sensor as possible.

2.4.2 VoltageN/A

2.4.3 Current N/A

2.4.4 Power ELEC-002 Power consumption when on continuously shall not exceed 20 Watts.

[L4-CG-IP-RQ-657]

2.4.5 GroundingN/A

2.4.6 Battery LifeN/A

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2.4.7 Modes/State of Operation ELEC-003 Instruments shall return to a defined operational state upon being

depowered and repowered. [L4-CG-IP-RQ-447]

2.4.8 Isolation N/A

2.4.9 Interface to hygrometerELEC-004 The Direct Covariance Flux System shall provide a power connection for

a commercial fast-response hygrometer capable of supplying in the range 10-30 VDC.

ELEC-005 The Direct Covariance Flux System shall provide a serial (RS-232, RS-422, RS-485) communications connection for a commercial fast-response hygrometer capable of baud rates between 4,800 and 56,700.

2.5 Data Storage and Processing

2.5.1 Storage CapacityDATA-001 Instruments shall provide non-volatile internal data storage. The data

storage size shall accommodate data taken at the typical rate (20 Hz) over the duration of the deployment interval (see OPER-005).

DATA-002 The DCFS data logger shall be capable of logging raw sensor data at up to 20Hz.

DATA-003 Instruments should internally store calibration and sensors serial numbers. This is an objective.

2.5.2 Data Averaging DATA-004 The instrument package shall provide data averaging capabilities such

that 1 minute averages can be obtained from higher frequency sampling.

2.5.3 Onboard Data ProcessingDATA-005 The DCFS shall be capable of onboard processing to provide means,

variances, and covariances over specified blocks of time. [L4-CG-IP-RQ-655]

DATA-006 The DCFS shall be capable of outputting processed data in near real time. [L4-CG-IP-RQ-656]

2.5.4 Post-recovery Data ProcessingDATA-007 The DCFS shall be provided with a software package to carry out all

processing of the raw data to yield covariance flux estimates. The software package shall be fully documented with a copy of the code and all of the equations and steps in the processing.

2.6 Software/Firmware

SOFT-001 Serial instruments requiring a break signal should be capable of emulating the break by a software character sequence. This is an objective.

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2.7 Platform Interfaces

2.7.1 MechanicalN/A

2.7.2 Electrical INTF-001 The instrument package shall connect to the platform controller for power

and communications (the connector type is on the CGSN platform controller housing are TBS and will be detailed in an interface control document).

INTF-002 The instrument should include a standard type of OOI bulkhead connector on the instrument housing (see Appendix 4.1). This is an objective.

INTF-003 The instrument package shall operate from a supply voltage of either 12 VDC +/- 5% or 24 VDC +/- 5%. [L4-CG-IP-RQ-287]

2.7.3 Data and Communicationa) Timing

INTF-004 Instruments shall provide time-stamping capabilities or latency characterization between data sampling and data output. [L4-CG-RQ-450]Preferences for instrument time stamping capabilities are as follows (best first): Time stamp embedded in every data record to the design accuracy of

the instrument's clock, using ISO 8601 compliant timestamp Time stamp embedded in every data record to the design accuracy of

the instrument's clock, using another described, parseable timestamp format

Time stamp every data sequence, with fixed time between every data record

Fully characterize the latency between data sampling and appearance of the data at the output connector

Time stamp embedded in every data record, with precision that is less than the accuracy of the instrument's clock, using ISO 8601 compliant timestamp

Time stamp embedded in every data record, with precision that is less than the accuracy of the instrument's clock, using another described, parseable timestamp format.

b) Clock Synchronization INTF-005 Instruments should have an internal clock. This is an objective.INTF-006 Instruments with internal clocks shall be capable of time synchronization.

[L4-CG-IP-RQ-449]c) Data Rate

INTF-007 Instruments should have a user-settable baud rate, up to 115,200 baud for serial interfaces. This is an objective.

d) Data FormatN/A

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e) Protocols INTF-008 Instruments with an Ethernet interface should provide an auto-discovery

mechanism, (e.g., PUCK, Universal Plug’n’Play’, ZeorConf/Bonjour). This is an objective.

f) Physical InterfaceN/A

g) Electrical InterfaceINTF-009 Instruments shall communicate (Data and Commands) while deployed

with the OOI infrastructure (e.g. CI device driver or platform interface) via at least one of the following interfaces: Ethernet (10/100 Mb), or serial EIA standards: RS-422, RS-485, or RS-232. [ L4-CG-IP-RQ-297, L4-CG-IP-RQ-291]

h) Remote AccessINTF-010 Instruments shall be capable of being remotely accessed and controlled

via the communication interface. [L4-CG-IP-RQ-294]INTF-011 All data stored on the instrument shall be accessible remotely over the

communication interface.INTF-012 Instruments should support remote firmware installation. This is an

objective.i) Modes

INTF-013 Instruments should allow polled and asynchronous mode operation. This is an objective.

2.8 Compliance

COMP-001 To the greatest extent practical, all CGSN infrastructure shall be compatible with applicable national and international standards, including those of the IEEE, ANSI, and IEC.

2.9 Safety

N/A

2.10 Shipping and Storage

2.10.1 ShippingSHIP-001 Instruments shall be provided with a reusable transportation case with

shock mounting.SHIP-002 Instrument Transportation Cases must fit within an ISO shipping

container. [L3-CG-RQ-494]SHIP-003 Instruments in their transportation cases shall be capable of surviving

shipping conditions defined by ASTM D4169 truck assurance level 1. [L3-CG-RQ-432]

2.10.2 StorageSHIP-004 Instruments should be capable of being stored with out damage or

degradation between -20° and 50° C for periods of up to 12 months. This is an objective.

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2.10.3 Safe Handling SHIP-005 Instrument transportation cases shall have external labels specifying

safe handling precautions.

2.11 Identification

2.11.1 Physical Markings IDNT-001 All components of the direct covariance flux instrument package shall be

marked indelibly on an exterior surface. Marking shall include: Manufacturer’s part number Unit serial number CGSN part number as defined below:

P/N 3305-00004-00001IDNT-002 The turbulent wind velocity sensor and the housing of the platform motion

sensors shall be labeled and have permanent marks to guide the correct alignment of these sensors on the buoy tower.

2.12 Quality

2.12.1 Product QualityQUAL-001 Instrument packages shall be manufactured in accordance with the

manufacturer’s best practices. Records of quality assurance tests and inspections shall be available for review by the purchaser.

QUAL-002 A First Article Testing report shall be provided with each first article unit delivered.

QUAL-003 A certificate of compliance shall be provided with each delivered unit. The certificate of compliance shall be supported with copies of the Factory Acceptance Test report and calibration records for each sensor following integration into the unit.

QUAL-004 The materials used in construction of the instrument packages shall be chosen and treated in such a way as to reduce the levels of wear, corrosion and deterioration to allow multiple deployments of each unit.

3.0 Documentation and Support

N/A

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4.0 Appendices

4.1 Preferred OOI Standard Connector types.

Instruments should use an MCBH connector installed on the housing. The number of pins, and pinout assignments, should be appropriate to the communication protocol of the instrument, and as shown in the table below. This is an objective.

If the instrument is deployed below the surface, the underwater connector should be water blocked so that there is a back-up o-ring seal in the event that the elastomeric sealing surface delaminates from the metal shell. This is an objective.(An example of a 6 pin water blocked connector is the MCBH(WB)-6-FS-Ti, manufactured by Teledyne Impulse.)

Protocol RS-232 RS-232 RS-485 (half duplex)

RS-485 (full duplex)

Pin # 4 Pin 6 Pin 6 Pin 8 Pin1 Gnd Pwr Gnd Pwr Gnd Data Gnd2 RXD RXD Data B+ RD B+3 TXD TXD Data A- RD A-4 12Vdc 12Vdc* 12Vdc* Reserved5 24Vdc* 24Vdc* TD A-6 Data Gnd Data Gnd TD B+7 Pwr Gnd8 +Vdc9

10* Only one voltage will be populated, depending on instrument input power needs.

Preferred vendors include: Teledyne Impulse SubConn, Inc.9855 Carroll Canyon Road www.subconn.comSan Diego, CA 92131impulse@teledyne.com mac-us@macartney.com

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