Sequoia LISST-AOBS Manual de usuario

LISST-AOBS

Super-Turbidity Sensor

Version 2

User’s Manual

Version 2.2

November, 2021

Describes LISST-AOBS Version 2, serial numbers 6246 and higher.

For earlier Version 1 LISST-AOBS models, see manual version 1

Sequoia Scientific, Inc.

2700 Richards Road Suite 107

Bellevue, WA, 98005, USA

Phone: +1 855-753-3313

[email protected]; www.SequoiaSci.com

FOR TECHNICAL ASSISTANCE please contact your local Distributor, or Sequoia if the instrument

was purchased directly from Sequoia. Please be sure to include the instrument serial number with

any correspondence.

A list of local Sequoia distributors can be found at our website

http://www.sequoiasci.com/about/contact/distributors

Sequoia Scientific, Inc. can be reached at

[email protected] or by phone at +1-855-753-3313

This page intentionally blank

Table of Contents 
INTRODUCTION ........................................................................................................................................1
LISST-AOBS system parts........................................................................................................................1
Data outputs ..........................................................................................................................................1
Data interface and logging options........................................................................................................1
Anti-fouling wiper...................................................................................................................................2
Sampling modes and start-up sequence ................................................................................................2
Wi ing.....................................................................................................................................................2
General Use and Care.............................................................................................................................3
OPERATION WITH THE NEXSENS X2 LOGGER ............................................................................................4
About the X2 and X2-SDL .......................................................................................................................4
Logging process......................................................................................................................................4
Data storage & transmission .................................................................................................................4
WQDataLIVE...........................................................................................................................................4
CONNECT software.................................................................................................................................5 
SDI-12 addressing...................................................................................................................................5
Initial setup.............................................................................................................................................5
Parameter labels on WQDataLIVE .........................................................................................................5
SDI-12 OPERATION DETAILS......................................................................................................................7
Overview ................................................................................................................................................7
Addressing..............................................................................................................................................7
Sampling and averaging ........................................................................................................................7
Control of the anti-fouling wiper............................................................................................................7
SDI-12 COMMAND REFERENCE .........................................................................................................................8
RS-232 OPERATION...................................................................................................................................9
Overview ................................................................................................................................................9
USB-powered operation .........................................................................................................................9
Port parameters .....................................................................................................................................9
Command prompt ..................................................................................................................................9
RS-232 COMMAND REFERENCE.......................................................................................................................10 
LISST-ABS WINDOWS SOFTWARE ...........................................................................................................13 
Wiring Requirements ...........................................................................................................................13 
Installing Software ...............................................................................................................................13 
Connecting to an Instrument................................................................................................................13 
Software Configuration Options...........................................................................................................14 
Logging Data........................................................................................................................................17 
Settings/Tools.......................................................................................................................................18 
HOW SUPER-TURBIDITY MEASUREMENT WORKS...................................................................................21 
Acoustic................................................................................................................................................21 
Optical..................................................................................................................................................21 
Pairing ABS with turbidity ....................................................................................................................22 
Measuring Pairing Factor.....................................................................................................................22 
Pairing Results......................................................................................................................................22 

Interpreting LISST-AOBS Data ..............................................................................................................23 
CONNECTION DETAILS ............................................................................................................................24 
Pin functions.........................................................................................................................................24 
Male connector numbering..................................................................................................................24 
Female mating connector numbering ..................................................................................................24 
Cables...................................................................................................................................................24 
SPECIFICATIONS......................................................................................................................................25 
APPENDIX: HOW THE LISST-ABS WORKS.................................................................................................26 
REVISION HISTORY..........................................................................................................................................28 
 
 

INTRODUCTION

LISST-AOBS

system parts

The LISST-AOBS is a system with three main parts:

1. LISST-ABS acoustic backscattering sensor

2. Turner Designs Turbidity Plus™ optical backscattering sensor

3. A Y-cable/adapter connecting the two sensors.

The combination of acoustic and optical sensors provides measurements

of total s concentration that are much less affected by particle

size than standard turbidity measurements (see How Super-Turbidity

Measurement Works on page 21).

For complete technical details of the Turbidity Plus™, see the User’s

Manual at https://www.turnerdesigns.com/turbidity-plus-submersible-

sensor.

Data outputs

The LISST-AOBS has three outputs:

1. ABS standardized concentration in mg/liter, as calibrated with 75-

90 µm microspheres.

2. Turbidity Plus output in Volts (not calibrated in terms of

concentration or NTU).

3. AOBS concentration (Super-Turbidity) in mg/liter, a combination

of the ABS and OBS measurements as described in Pairing ABS

with turbidity on page 22.

Data interface

and logging

options

LI T-AOBS has two digital interfaces: RS-232 and SDI-12. Both interfaces

are available for communication at any time, although normally you will

communicate using only one interface at a time. NOTE: the RS-232

interface will not respond when an SDI-12 command is in progress.

Any logger that supports SDI-12 version 1.3 or higher can use the SDI-12

interface. Sequoia has teamed with NexSens Technology to integrate the

LISST-AOBS with the NexSens X2 logger family, using SDI-12. The X2 can

automatically detect a LISST-AOBS and deliver its data, with data from

other connected sensors, through Wi-Fi, cellular, radio, or satellite

channels. See more in Operation with the NexSens X2 logger on page 4.

If operating with a logger other than the X2 family, see SDI-12 Operation

on page 7. For details of the RS-232 interface, see RS-232 Operation,

starting on page 9.

Anti-fouling

wiper

Optical backscattering measurements are much more sensitive to

biofouling than acoustic measurements. To prevent fouling, the Turbidity

Plus includes an integrated anti-fouling wiper. Operation of the wiper

takes about 10 seconds, and is activated in the following ways:

1. Upon power-up,*

2. By certain SDI-12 commands,

3. By the RS-232 WI or WIPE command

4. If operating in the free-running RS-232 mode (after automatic

start or GO command), every 10* minutes.

*These are the default factory settings, but can be changed via RS-

232 with the OBSSET command (see Set automatic wiping on page

11)

Sampling modes

and start-up

sequence

The LISST-AOBS RS-232 interface can operate in either polled or free-

running mode.

The default mode is free-running. Upon power-up, after running the

Turbidity Plus wiper if applicable, the LISST-AOBS will start sending one

data sample per second via RS-232, and continue indefinitely. The host

data system is not required to send any commands in this mode.

The free-running mode can be stopped at any time by sending 3 control-

C or carriage-return characters via RS-232, or by sending any SDI-12

command.

When not in free-running mode, the LISST-AOBS can receive other RS-

232 commands, as described in the RS-232 Operation section, including

commands for collecting and sending individual samples.

The SDI-12 interface is always polled: the logger or other data system

must request a sample, then request the data from that sample.

Wi ing

For SDI-12 operation, as with any SDI-12 device, only three connections

are required: power (nominally 12 V), ground, and SDI-12 data. However,

for compatibility with existing LISST-ABS cabling, the LISST-AOBS uses the

same 8-pin connector as a standard LISST-ABS. For details, see

Connection Details on page 24. The user must determine how to connect

the LISST-AOBS to the SDI-12 logger. Sequoia Scientific can provide cable

pigtails for this purpose.

RS-232 operation requires four connections: power, ground, transmit,

and receive. Typically these connections will be made to a computer

COM port, or a USB adapter, or to a data logger. The user must

determine to exact wiring depending on the mating device.

General Use and

Care

•Do not use abrasives or harsh solvents for cleaning. These could

damage the plastic exterior.

•Use special caution with the light-colored transducer disk on the

face of the LISST-ABS. Damage to the transducer can severely

affect accuracy.

•Be sure water flows freely through the area directly in front of the

LISST-AOBS, and within 10 cm of the ABS face. Any solid object

within 10 cm can interfere with the measurements.

OPERATION WITH THE NEXSENS X2 LOGGER

About the X2

and X2-SDL

The NexSens X2 is a data logger that directly supports the LISST-AOBS,

using the SDI-12 protocol, as well as many other SDI-12 sensors. The

standard X2 is in a compact weatherproof (but not submersible) housing.

The X2-SDL is functionally identical, but is submersible to a maximum

depth of 60 meters.

Sequoia Scientific and NexSens offer complete packages that include an

X2 or X2-SDL, and all necessary cabling.

For detailed information, see the X2 Document and Resource Library at

https://www.nexsens.com/knowledge-base-v2/data-loggers/x2, and the

X2-SDL resources at https://www.nexsens.com/knowledge-base-v2/data-

loggers/x2-sdl.

Logging process

X2 loggers are optimized for long-term monitoring applications, in which

they wake periodically, collect a sample, then return to low-power sleep

mode until the next sample. The factory-default sample period is 10

minutes, but can be changed through the X2’s Wi-Fi interface, or through

the CONNECT software.

Data storage &

transmission

The logging of LISST-AOBS data on an X2 is controlled by a script provided

with the X2. The standard script

1. powers the LISST-AOBS 10 seconds before the scheduled sample

time, running the anti-fouling wiper on the turbidity sensor, then

2. collects a 30-second average of LISST-AOBS data, and

3. logs the averaged values.

X2 loggers store data in their onboard memory, but also support

automatic uploading through a Wi-Fi, cellular, radio, or satellite

connection (depending on hardware configuration). Data then appear in

near-real-time on the WQDataLive website. Raw data can also be

offloaded directly to a computer through a USB port.

WQDataLIVE

WQData LIVE is a web-based platform for collecting and displaying data

from Nexsens loggers. Users of X2 loggers can set up projects on this

platform, free of charge. A project can have one or more X2 loggers

associated with it, and those loggers can automatically deliver their data

to the site through a WiFi, cellular, radio, or satellite connection

Tabla de contenidos

Manuales populares de Escáner de otras marcas

Plustek

Plustek Scanner Manual de usuario

Z/I Imaging

Z/I Imaging PhotoScan 2001 Manual de usuario

Renkforce

Renkforce DS100-5M Manual de usuario

Image Access

Image Access WideTEK A2 Manual de usuario

Canon

Canon imageFORMULA CR-120N Manual de usuario

Fujitsu

Fujitsu FI-4860C2 Manual de usuario

GeoSlam

GeoSlam ZEB Horizon Instrucciones de instalación

Kodak

Kodak i5800 Scanner Manual de usuario

Kodak

Kodak i7300 Manual de usuario

Revopoint

Revopoint POP Manual de usuario

Fujitsu

Fujitsu fi-4860C Manual de usuario

Eddyfi Technologies

Eddyfi Technologies Floormap X Manual de usuario

Faselase

Faselase F6 Manual de usuario

Fujitsu

Fujitsu CardMinder Manual de usuario

Uniden

Uniden BC340CRS Manual de usuario

Infinite Peripherals

Infinite Peripherals INFINEA TAB M Manual de usuario

Mustek

Mustek PageExpress 4800 Pro Manual de usuario

Optex

Optex 750830 Manual de usuario