Campbell Scientific DOT600 User Manual
DOT600 Roadbed
Water Content Meter
1/10
Copyright © 2010
Campbell Scientific, Inc.
Warranty and Assistance
The DOT600 ROADBED WATER CONTENT METER is warranted by
CAMPBELL SCIENTIFIC, INC. to be free from defects in materials and
workmanship under normal use and service for twelve (12) months from date
of shipment unless specified otherwise. Batteries have no warranty.
CAMPBELL SCIENTIFIC, INC.'s obligation under this warranty is limited to
repairing or replacing (at CAMPBELL SCIENTIFIC, INC.'s option) defective
products. The customer shall assume all costs of removing, reinstalling, and
shipping defective products to CAMPBELL SCIENTIFIC, INC. CAMPBELL
SCIENTIFIC, INC. will return such products by surface carrier prepaid. This
warranty shall not apply to any CAMPBELL SCIENTIFIC, INC. products
which have been subjected to modification, misuse, neglect, accidents of
nature, or shipping damage. This warranty is in lieu of all other warranties,
expressed or implied, including warranties of merchantability or fitness for a
particular purpose. CAMPBELL SCIENTIFIC, INC. is not liable for special,
indirect, incidental, or consequential damages.
Products may not be returned without prior authorization. The following
contact information is for US and International customers residing in countries
served by Campbell Scientific, Inc. directly. Affiliate companies handle
repairs for customers within their territories. Please visit
www.campbellsci.com to determine which Campbell Scientific company
serves your country.
To obtain a Returned Materials Authorization (RMA), contact CAMPBELL
SCIENTIFIC, INC., phone (435) 753-2342. After an applications engineer
determines the nature of the problem, an RMA number will be issued. Please
write this number clearly on the outside of the shipping container.
CAMPBELL SCIENTIFIC's shipping address is:
CAMPBELL SCIENTIFIC, INC.
RMA#_____
815 West 1800 North
Logan, Utah 84321-1784
For all returns, the customer must fill out a “Declaration of Hazardous Material
and Decontamination” form and comply with the requirements specified in it.
The form is available from our website at
completed form must be either emailed to repair@campbellsci.com
435-750-9579. Campbell Scientific will not process any returns until we
receive this form. If the form is not received within three days of product
receipt or is incomplete, the product will be returned to the customer at the
customer’s expense. Campbell Scientific reserves the right to refuse service on
products that were exposed to contaminants that may cause health or safety
concerns for our employees.
www.campbellsci.com/repair
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or faxed to
DOT600 Table of Contents
PDF viewers note: These page numbers refer to the printed version of this document. Use
the Adobe Acrobat® bookmarks tab for links to specific sections.
1. General Description.....................................................1
2. What Parts Comprise the DOT600 .............................2
3. Specifications ..............................................................3
4. User Interface for Measurement and Control............4
4.1 The Keypad...............................................................................................4
4.2 Main Menu ...............................................................................................4
4.2.1 Project Information.........................................................................5
4.2.2 Test ID Data....................................................................................5
4.2.3 Make Measurements.......................................................................6
4.2.4 System Menu ..................................................................................6
4.2.5 Measurement Report.......................................................................6
5. Making Measurements with the DOT600...................7
5.1 Tare Scale.................................................................................................8
5.2 Fill Sample Chamber................................................................................9
5.2.1 Weigh the Sample...........................................................................9
5.3 Compress Sample and Measure Water Content......................................10
5.3.1 Write Measurement Data to Record..............................................13
5.3.2 Start New Test...............................................................................14
5.4 Removing Samples.................................................................................14
6. Detailed Description..................................................15
6.1 Power System.........................................................................................15
6.1.1 Battery, Charger and Power Switch..............................................15
6.2 CR850 Datalogger..................................................................................15
6.3 Water Content Measurement..................................................................15
6.3.1 Electronics and Waveguide...........................................................15
6.3.2 Sample Chamber Volume and Compression Force......................16
6.3.3 Water Content Calibration............................................................16
7. Maintenance...............................................................16
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DOT600 Table of Contents
Appendix
A. Design and Calibration ...........................................A-1
Figures
A.1 Description of Basic Technology........................................................ A-1
A.2 Description of the Modified Device.................................................... A-2
A.3 Detailed Description of any Field and Laboratory Work.................... A-2
A.4 Displacement Sensor Calibration........................................................ A-3
A.5 Sensitivity of Weight Position on Scale Surface................................. A-4
A.6 Soil Water Content Calibration........................................................... A-4
A.7 Description of the Test Performed and Factors Which Could Have
Effect on Results of DOT600 Measurements....................................A-5
1. Cross sectional drawing shows mounting of battery and charger/
regulator beneath panel ..................................................................... 15
A-1. Typical scale calibration. The standard error is 0.013 g.................... A-3
A-2. Typical calibration data for the displacement sensors.......................A-4
A-3. Partial calibration set showing calibration data and equation.
The effect of clay content on sensor response is apparent ..............A-5
Tables
1. Common and Special Keypad Functions................................................... 4
2. Information in the report............................................................................ 6
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DOT600 Roadbed Water Content Meter
1. General Description
The DOT600 is a portable device for measuring the water content of soils used
in construction of roads, parking lots, foundations, etc. Samples collected from
field sites are compacted using a vertical stress of (15-45 PSI), then the water
content is measured using dielectric permittivity sensitive methods. A separate
scale and magnetic linear sensors measure the sample volume and mass, which
allows calculation of bulk density and conversion of the measured volumetric
water content to gravimetric water content. Measurement results are written to
a data table for permanent record. All measurements are controlled by a
Campbell Scientific CR850 datalogger which includes an 8 line display and
keypad for interface.
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DOT600 Roadbed Water Content Meter
2. What Parts Comprise the DOT600
DOT600 components are housed in a rugged case. Contained in the case are:
1. Cable to charge DOT 600 from AC power source
2. Sample chamber base
3. Sample chamber cylinder
4. Ratcheting box-end wrench
5. Compression cap
6. Sieve, #4 mesh
7. DOT600 operating manual
8. RS-232 serial cable
9. PC200W software
10. External Keypad
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3. Specifications
Power
Battery
2.9 Ahr rechargeable sealed lead-acid battery
Operating temperature range: -20°C to 60°C
Standby charge retention at 20°C for one year = 95%
Lifetime approximately 500 cycles with discharge to 50% followed by
recharge.
See section Power System
Scale
Capacity = 1000 g
Accuracy = ±0.032%
Repeatability = 0.02% FS
The scale has overload protection in both the up and down d i rect i ons d uring
shipping. But it only has overload protect i o n in the dow n di rect i o n du ri n g use.
Water Content Measurement
Resolution = 1% volumetric water content
Precision = 0.75% volumetric water content
DOT600 Roadbed Water Content Meter
Resolution is the minimum change in the measured parameter, water content,
that the sensor can repeatedly detect.
Precision is the expected range for repeated measurements on the same sample.
Accuracy is defined by comparing DOT600 measured water contents to
independently determined values. The independent method is water content by
gravimetric method (weighing sample before and after oven drying).
The DOT600 water content measurement uses a calibration to convert sensor
output period to volumetric water content. This calibration was derived at the
factory for various soil types. The calibration coefficients used are determined
by the material type selected by the user. Repeated measurements on the sandy
loam soil over the water content range from air dry to about 70% saturation
show deviations from independent measurements of less than ±1.5%
volumetric water content.
Since the gravimetric water content measurement uses sample volume and
weight to convert from measured volumetric water content, the accuracy of the
gravimetric water content will be less than the volumetric value because of
inherent errors of the volume and weight measurements.
Sample Volume and Applied Force Measurement
Sample Volume
±1.5% for compressed sampled with thickness between .400 in to 1.000 in.
Sensitive Volume
The electromagnetic field penetrates the sample 0.39 in. Sensitive volume is
about 3.5 in
Applied vertical stress range and accuracy
Applied vertical stress: 0 to 45 PSI.
Applied vertical stress measurement accuracy: 1.7 PSI.
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.
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DOT600 Roadbed Water Content Meter
4. User Interface for Measurement and Control
The Measurement and Control Datalogger has a built-in ruggedized
membrane-switch keypad for control and a display with 8 lines and 21
characters per line. Measurement control uses a hierarchical structure of
menus and submenus.
4.1 The Keypad
The keypad keys that are commonly used or have special functions are listed in
Table 1.
TABLE 1. Common and Special Keypad Functions
Key Usage
[2] and [8] Navigate up and down through the menu list one line at a time
[Enter] Selects the line or toggles the option of the line the cursor is on
[Esc] Backs up one level in the menu
[Home] Moves cursor to top of the list
4.2 Main Menu
[End] Moves cursor to bottom of the list
[BkSpc] Delete character to the left
[Shift] Change alpha character selected (shown at top right)
[Num Lock] Change to numeric entry
The Main Menu is the starting point for each set of measurements and is
discussed in this section.
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4.2.1 Project Information
A 9-digit alphanumeric value can be entered to identify the project. The
current date is automatically set. The project information is written to the
measurement report (see Measurement Report section). Data can be displayed
in either Imperial or SI units.
4.2.2 Test ID Data
DOT600 Roadbed Water Content Meter
The elements of this submenu allow the user to enter information about a set of
measurements. Scroll to the element and press the Enter button to enter value.
The entered information will appear in the report. Abbreviations such as
“Matrl Type” are used because the number of characters used in a field is
limited.
Parameter Description
Tester Enter name of person performing the measurements
Test # Enter a numeric test identifier
Material Type
(Matrl Type)
Station (X-Coor)
Offset (Y-Coor)
Depth (Z-Coor)
Press Enter and scroll the pick list to select a soil type,
or select “custom” for custom material. The sandy
loam calibration has been found to work for most
typical soils
Enter value to identify sample location(s) in X, Y and
Z coordinates
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