Campbell-scientific OBS-5+ Sediment Concentration Monitor and Pressure Manual de usuario

OBS-5+ SystemRevision: 11/13Copyright © 2008-2013Campbell Scientific, Inc.

OBS-5+ System 4. Overview FIGURE 4-1 shows the dimensions of the OBS-5+, the sensors in the sensor endcap, and underwater connection. Detailed speci

OBS-5+ System FIGURE 4-2. Schematic of optical system 4.2 SSC-Measurement Principle In FIGURE 4-2, suspended particles scatter light from the NIR

OBS-5+ System FIGURE 4-3. Sample calibration curves (fine and bold lines), lookup tables I, II, and III (bold curves), and sediment concentrations p

OBS-5+ System FIGURE 4-4. Calibration curves for four different sediments and SSC values for near-detector peaks (colored arrowheads). 5. Specifica

OBS-5+ System 5.2 Accuracy Mud: 2.0% of reading Sand: 4.0% of reading Pressure: 0.5% of full scale Turbidity: 1.5% of full scale 5.3 OBS-5+ Sensor

OBS-5+ System 6. Operation 6.1 Instrument Setup 6.1.1 Mounting Suggestions Maximum depth for the OBS-5+ is limited by the installed pressure sensor

OBS-5+ System 6 – 18 V d.c. (Red) Power GND (Black) FIGURE 6-1. Electrical connections 867DB-9386.1.3 Logging Data In applications where a survey

OBS-5+ System For extended deployment time, lithium batteries are a good alternative to alkaline batteries. Campbell Scientific sells a C-cell-sized

OBS-5+ System data with a PC or uploading data from the OBS-5+, 5) importing data into a spreadsheet, and 6) plotting data with OBS-5+ Utility. 6.2.2

OBS-5+ System 6.2.3 Pull-Down Menus The OBS-5+ Utility has four pull-down menus for File, OBS-5+, View, and Help. The File menu allows you to sel

OBS-5+ System adjustment takes two seconds. If your PC is set to the wrong rate for some reason, use the check box to select ONLY change host compute

OBS-5+ System 2) Wave your hand in front of the OBS-5+ sensor; the turbidity and SSC levels on the top plot will fluctuate as data scrolls across the

OBS-5+ System 1) Measures of central tendency, including the mean and median. 2) Measures of variation or spread in sample values, including the st

OBS-5+ System recorded. Select the longest interval that will show the changes in turbidity and water depth that you wish to investigate. Rate sets

OBS-5+ System 3) Click the lookup table icon and select a calibration table for your survey. The last active table will be used otherwise. 4) Cl

OBS-5+ System 6.2.11 Cyclic Sampling This mode is for logging data at regular intervals such as 1, 10, 15, 30, etc. minutes, for example. 1) Request

OBS-5+ System 6.2.12 Data Retrieval 1) Remove dummy plug and connect OBS-5+ to PC with test cable (FIGURE 6-1). 2) Run OBS-5+ Utility. 3) Open the

OBS-5+ System 2) Click Open and select a file to view. Print will print a graph when Open As Plot is selected. To print a text file, select Open

OBS-5+ System 7. Calibration 7.1 Sediment and NTU Calibration In addition to the concentration, the size, shape, and reflectivity of suspended sed

OBS-5+ System FIGURE 7-1. Manual (left) and automatic (right) sediment suspenders 7.1.1 General Guidance The OBS-5+ uses response curves from

Warranty “PRODUCTS MANUFACTURED BY CAMPBELL SCIENTIFIC, INC. are warranted by Campbell Scientific, Inc. (“Campbell”) to be free from defects in materi

OBS-5+ System from the descending limb of the near detector curve. A calibration consists of a set of 15 to 30 calibration points that each includes

OBS-5+ System TABLE 7-1. Schedule of Concentrations for Sediment Calibrations MUD (D60 < 62 µm) Sand (D60 > 62 µm) Low SSC (0-5 g/l) Mid-ra

OBS-5+ System Sediment concentrations can also be calculated manually with the following equations: ⎥⎦⎤⎢⎣⎡+=ssisMVMl/gρ g/l) 103 x 2.65(usually densit

OBS-5+ System 3) Click the button to view the list of lookup tables stored in the unit. Select an EMPTY Table number for the sediment calibration.

OBS-5+ System 5) Enter 0.001 in the value box and click the Record button to log the clear-water data point. The unit will take 1,200 measurements

OBS-5+ System 8) Withdraw about 10 ml of water from the suspender and add it to the tea cup containing the dry sediment. Stir the water-sediment mix

OBS-5+ System the FD curve where it starts decay exponentially, also 10 on FIGURE 7-2 9. Points ‘b’ and ‘c’ will usually have the same numerical valu

OBS-5+ System FIGURE 7-5. OBS-5+ in 100 mm cup 6) Add enough 250-NTU standard to cover the sensor end (FIGURE 4-1) and swipe bubbles off the sapphi

OBS-5+ System corroded surfaces of the contact and track with a scouring pad and reassemble unit. Unit does not communicate with PC. There are several

OBS-5+ System FIGURE 8-1. Internal components OBS-5+ or pressure sensor malfunction. • Open unit and inspect for: 1) broken sensor wires, and 2) lo

Assistance Products may not be returned without prior authorization. The following contact information is for US and international customers residing

OBS-5+ System Bright sun near the surface (< 2 m) or black-colored sediments cause erroneous OBS readings. Do not survey in shallow water between 1

OBS-5+ System 9.3 Batteries The unit runs on three, C-size, alkaline batteries. Buy the expensive ones with the longest expiration date (“use before

OBS-5+ System pn 4576 Alkaline C-Cells Batteries pn 20806 OBS-5+ Test Cable, 2 m (6.5 ft) pn 21381 7-piece Allen Wrench Set, 5/64 to 3/16 Ball End pn

OBS-5+ System FIGURE 10-1. Effects of sediment size 10.2 NIR Reflectivity The output of an OBS-5+ will increase with the NIR reflectivity of suspen

OBS-5+ System FIGURE 10-2. Near-infrared reflectivity of minerals Reactive Sensitivity 10.3 Particle Shape, Flocculation, and Disaggregation Parti

OBS-5+ System FIGURE 10-3. Effects of disaggregation methods Finally, flocculation of clay particles in estuaries can affect sensitivity by causing

OBS-5+ System 38 11. References Black, K.P., M.A. Rosenberg. 1994. Suspended Sand Measurements in a Turbulent Environment: Field Comparison of Optica

Appendix A. Turbidity Standards AMCO Clear, supplied by GFS Chemicals (www.gfschemicals.com), is an approved calibration standard and is the one we

Appendix A. Turbidity Standards In the USA, formazin is a primary standard for the calibration of turbidimeters. The median particle size of formazi

Appendix A. Turbidity Standards We must emphasize that unlike SSC, which has physical units, turbidity values (NTUs, FTUs, etc.) do not. Therefore,

Table of Contents PDF viewers: These page numbers refer to the printed version of this document. Use the PDF reader bookmarks tab for links to spec

Appendix A. Turbidity Standards A-4

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Table of Contents 7. Calibration ...20 7.1 Sediment and NTU Calibration ...

Table of Contents 8-1. Internal components ...31 10-1. Effects of sediment si

Table of Contents iv

OBS-5+ System 1. Introduction The manual describes the features of the OBS-5+®, as well as its use for surveys and battery-powered, internal-storage