Campbell VWANALYZER, VWA User Manual

Tips:

• Return to the Main Menu by pushing the left soft key several times.

• Carry spare batteries (5-AA) in the carrying case.

• A continuous measurement can display engineering units when linked to a Site/Sensor
with an engineering unit conversion applied.

• Leave 1–2 mm of exposed sensor wire on datalogger/multiplexer wiring for VWA

connection . Always disconnect automated system power prior to VWA connection.

Denitions:

Sensor: An individual vibrating wire sensor. A VWA can store up to 880
unique sensors (40 sites, 22 sensors/site).
Site: A project or geographic location containing up to 22 sensors.
User: Operator name and information.

Wiring Guide

VWA Cable Common Sensor Sensor

-RED -ONG Cable Colors

1

Description

Red

2

Orange2 Red or Orange VW Gage
Black2 Orange2 Black White w/Orange VW Gage
Green2 Blue2 G reen or Blue Therm/RTD
White2 Blue2 White White w/Blue Therm/RTD
Blue Yellow Bare/Clear Drain Wire

1

If sensor wiring does not match the table, refer to the sensor manufacturer manual to determine the VW gage

wire leads. Some sensors may not have a thermistor or RTD (temperature measurement).

2

Vibrating wire leads are interchangeable (black and red instead of red and black); thermistor leads are similarly

interchangeable.

Read & Record

There are three options to save data when using Read & Record.

• Single is used when sensors won’t be repeatedly measured in the future (installation

record, baseline reading, troubleshooting).

• Site/Sensor is used when sensors will be repeatedly measured and data needs to be
linked to a site. Site/Sensor data is viewable in the eld for historical comparison.

• Continuous measures a single sensor at a user dened interval ranging from 1 second
to 15 minutes. Used to document installations, live eld testing (push-in-piezometer,
well pump test, sensor response, etc.), and for troubleshooting.

Notes:

• Measurements are not pressure or temperature compensated.

• Users can view all data. Sites are not user specic.

• See Measurement Screens for an explanation of displayed measurement results.

• Sites, Sensors, and Users can be created and edited either on the VWA, or with a PC and
keyboard using VwProjects.

Meet the Vibrating Wire Analyzer

Meet the Vibrating Wire Analyzer (VWA), the best vibrating wire (vw) eld reader
available. Field ready to quickly measure a sensor, save data, and communicate
results with custom PDF reports and spreadsheet output. Measurements are
geo-located with the integrated GPS allowing the VWA to verify locations and
walk you to your sensors. The large color display and VSPECTTM technology1 create
condence that you are getting the best measurement possible both in the eld
and in the oce. , when your measurements matter.

1

Protected under U. S. Patent No. 7,779,690

Data Retrieval

Files are transferred to a PC from the VWA using the USB port . Measurement data collected

with the Read & Record option is saved as a PDF and/or CSV le. A printable report (PDF) com­municates results quickly and professionally. Raw data les (CSV) can collect multiple sensors
(site) in a single le for additional spreadsheet analysis and reporting.

1 Expor t CSV les (optional)

• Navigate to the Main Menu. See Operation.

• Select Data. Choose and export CSV les.

2 Connec t VWA to a PC with USB

• Connect a PC to the VWA with a USB Mini-B cable.

• Power is supplied through the USB-PC connection.

3 Copy les to PC

• Find the USB ash memory device (VWA) on the PC.

• Data les are stored in either the PDF Reports or CSV Data folder.

• Copy les to the PC.
PDF • Ready to print PDF reports
Reports • Field documentation

CSV • Multiple measurements in one le
Data • Spreadsheet analysis

4 Ejec t VWA from PC

• Eject the VWA from the PC prior to disconnecting the USB cable.

VwProjects

VwProjects is a free software package for easier setup of Sites, Sensors, and Users with a PC.
VwProjects can be downloaded and installed from the VWA memory or from the internet, see

Downloads.

VwProjects is used to create and edit a project le that contains information about Sites, Sen-

sors, and Users. Project les can be used to back up or transfer information to other VWA devices.
See Using VwProjects for details about creating, editing, and transferring project les.

Notes:

• A project le contains information about Sites, Sensors, and Users. Measurement

data is saved in the PDF and CSV les, and is NOT saved or transferred in a project
le.

• You can preview a report title block when creating or editing a user in

VwProjects.

File Types

The following les are created or used with the VWA. Files are transferred with a USB connection
(see Data Retrieval).
PDF: Measurement Reports created using Read & Record.
CSV: Created by the VWA with Read & Record, use for further spreadsheet analysis; see
Data Retrieval.
VWA: A project le contains information about Users, Sites, and Sensors. Created in the
VWA or with VwProjects.
OBJ: Operating system le, created by Campbell Scientic. See Downloads.

MANUAL

Info

Link

9/2017

manual pn: 31913

Caution

• Avoid contact with water, see Precautions

• Transport/store in carrying case

• Measurements are not pressure or temperature corrected

!

Downloads

Visit www.campbellsci.com/vwanalyzer to download:

• VwProjects software

• Updated operating systems (updated Sensor Library)

• Manual (this document)

FIELD

QUICK TOUR

Vibrating Wire Analyzer

1 Power1, left soft key

2

2 Right soft key

2

3 Enter/select

3

4 Menu navigation arrows (4)
5 Serial number (SN)
6 Battery door
7 Battery door screws (2)
8 Elastic strap connection (2)
9 Measurement cable

10 USB por t (PC connection)
11 Measurement cable connection

1 Hold (2–3 s) to turn o

2

Soft keys select the displayed screen
option (when present)
3 Selects the highlighted option

1
2
3
4

5
6
7
8

9

10

11

OFFICE

PDF Reports

12 User specic title

1

13 Project Information

1

14 User-Dened Inputs
15 VSPECT D iagnostics

2

16 Field Notes
17 Sensor Frequency
18 Resistance (Thermistor/RTD)
19 Frequency Spectrum graph

2

20 9 Time Series graph

2

1 Entered manually or with a PC,
see VwProjects for details.

2

The VSPECT Measurement section
explains how to use and understand
VSPECT data.

12

13

14

15

16

17
18

19

20

Operation

1 Turn on the VWA

• Install/replace batteries as needed (5-AA)

• Push power button

2 Selec t/Create User

• Links user information to specic measurements

• User information is documented on PDF reports

3 Connec t Sensor (if measuring)

• Connect measurement cable . Keyed connector, do not force

• Match sensor and measurement cable colors . See Wiring Guide

4 Navigate the Main Menu

• Return to the Main Menu by pushing the left soft key several times.

1

11

9

Read:

Measure a sensor quickly,

Data is NOT saved

Read & Record:

Measure a sensor,

Data is saved

see Read & Record

Data:

Export data to CSV le, or view saved data
see Data Retrieval

Settings:

Change system, measurement, or power settings

1

9

10

10

12

• Quality

• PDF Reports

• Field Ready

9

Link

Read &
Record

Read

Data

Settings

Vibrating Wire Analyzer

Data SettingsRead Read &

Record

1

6

MANUAL

Equipment Inspection

Upon arrival, and before each use, inspect for the following items:

• VwAnalyzer • USB cable

• Carrying case • Phillips screwdriver

• Manual (this document) • 5-AA batteries

• Measurement cable • Hand strap

Precautions

• WARNING: Disconnect power from active automated systems prior to connecting and
measuring a sensor with a VWA on the automated system

• CAUTION: Avoid direct contact with water (IP-62)

• CAUTION: Store and transport in the protective case

• CAUTION: Measurements are not pressure or temperature compensated

• CAUTION: Do not force measurement cable connection ; cable ts one way

• CAUTION: Hold the device properly, do not hang/carry from measurement cable

Warranty & Service

• Warranted for one (1) year, www.campbellsci.com/terms

• For repair, see www.campbellsci.com/repair

• For assistance, call [phone]

Overview

The VWA uses patented VSPECTTM technology for the most reliable vw measurement available. The
VWA converts measurements to engineering units, generates a printable PDF report, and saves a
CSV summary le. The graphical display allows you to conrm sensor output and operation. VSPECT
technology eliminates disruptive noise interference and provides sensor diagnostics for the best
measurement possible. VSPECT noise immunity allows gages that are otherwise unreadable to be
evaluated with condence.
A project le maintains Site/Sensor information for 40 unique sites with 22 sensors per site. Site/
Sensor locations are geolocated, allowing the internal GPS to walk a user directly to the sensor. Site/
Sensor and user information can be created or edited on the device or with a computer using the free
VwProjects software.

Specications

Vibrating wire measurement

Resolution: 0.001 Hz RMS

Speed: 1 second (fastest)

Excitation: 2V, 5V, 12V (user selectable)

Accuracy: ±0.005% of reading

Method: VSPECT (Vibrating Wire Spectral Analysis), U.S. Patent No. 7,779,690

Temperature (resistance) measurement

Resolution: 0.01 Ω RMS

Accuracy: ±0.15% of reading

General information

1

Memory: 1,700 site/sensor measurements (most recent2)

40 unique sites, 22 sensors per site
240 single measurements (most recent2)
16,500 continuous measurements (most recent2)
80 MB USB memory (PDF, CSV, VWA, and other les3)

GPS: ± 5m (16.4 ft) typical; ±1 ms time sync (WGS 84 Datum)

Battery type/life: 5-AA (1.5 V)/20 hours continuous use

Weight: 0.34 kg (0.75 lb)
Dimensions: 200 x 100 x 58 mm (7.9 x 3.9 x 2.3 in)
Compliance: CE, RoHS

Operating Temp: (-20 to 70 °C)

Enclosure: IP62

EU Declaration of Conformity: www.campbellsci.com/vwanalyzer

1

Non-volatile memory stores data, reports, and project les

2

When memory is full, new data will overwrite the oldest data

3

Memory managed by users, les will need to be deleted/transferred when full

Operating System

A new operating system (OS) may be installed to update features or the sensor library. Back up all
data and the project le prior to working with the OS. A factory reset is done from System Settings.
OS update procedure:

1. Back up project les/data

2. Download the .obj le; see Downloads

3. Save le to the VWA root directory

4. Cycle power

5. Verify OS version in System Settings

Temperature Measurement

Most vw sensors have a resistance (thermistor/RTD) measurement to calculate sensor temperature.
When a sensor is selected with the sensor library, the equation and conversion coecients are
automatically selected for the manufacturer specic vw sensor. Users can view or create custom
temperature calculations in Measurement Settings. When using Read, Options can be selected
to quickly choose a temperature conversion.

Measurement Screens

When a sensor is measured, four screens display the results, the right soft key is used to
advance to the next screen.

1st Screen – Measurement

Summary screen setup by the user

• User selectable summary boxes (frequency, digits,
B-units, temp, ohms)

• Spectrum graph (optional)

• Change settings in Measurement Settings

2nd Screen – Details

Metadata including diagnostics
Tip: On-screen side arrows allow historic data
comparison

3rd Screen – Frequency Spectrum

Frequency spectrum graph

• Sensor signal is dened as the largest signal within
the frequency sweep range

• Visually compare the sensor signal to noise signals

4th Screen – Time Series

Time series graph

• Visually see the raw input signal

Sensor Library

The sensor library contains preprogrammed sensors from common vw sensor manufacturers. The library can be
accessed on the VWA or with VwProjects when a new sensor is created or edited using Site/Sensor. Use of
the sensor library enables:

• Manufacturer-recommended sweep frequencies

• Field conversion from frequency to engineering units

• Sensor specic calibration inputs

Notes:

• Engineering units reported are NOT corrected for temperature or barometric pressure

• Temperature is calculated with manufacturer specic conversions, see Temperature Measurement

• A Continuous measurement can graph the sensor response in engineering units when linked to a sensor with
calibration values applied

• Calibration inputs are unit specic to match manufacturer calibration sheets. When the selected output units
are dierent than manufacturer calibration units, an automatic unit conversion will be applied

Measurement Reports

Printable PDF measurement reports are saved when using Read & Record. There are two
types of measurement reports:

Single Measurement Report

Created when a measurement is performed from Site/Sensor or Single read. Use as eld
documentation, baseline reading, or as installation record.

Continuous Measurement Report

Optionally created with Continuous read. Use for monitoring changing eld conditions, or
during installation (push-in piezometer, well pump test, sensor response, etc.).

Using VwProjects

Project Files

A project le contains site, sensor, and user information. Project les can be shared between VWAs.
A project le can be used to:

• Back up Site, Sensor, and User information

• Transfer project le data to another VWA device

• Create or edit a project le on a PC with VwProjects

• Import/export project le in System Settings (see steps below)

• Maintain up to 20 users per VWA

• Maintain up to 880 unique sensors (40 sites, 22 sensors/site per VWA)

Note: A project le contains information about Sites, Sensors, and Users. Measurement data is

saved in the PDF and CSV les, and is NOT saved or transferred in a project le.

VwProjects

VwProjects uses a keyboard and PC to easily create and edit project les. The software can create a
new project le or open an existing project le created from a VWA or a PC. The screenshot
below illustrates the various buttons and capabilities of the software:

30 Create a new project le 35 Create and edit Sensors
31 Open an existing project le 36 Site/Sensor Information
32 Save the current project le 37 Sensor Details
33 Create and edit Users
34 Create and edit Sites

Note: When saving a project le on the VWA or PC , there are 2 save le options:

• Append File: New or changed information will be added or updated on the
VWA.

• O verwrite/ Backup le: When loaded to a VWA, all the old information will be
erased and overwritten with the new project le information.

Loading project le to a VWA

1. Connect to a PC with USB cable (see Data Retrieval)

2. Copy the project le from PC to the USB memory of the VWA

3. Eject the USB connection from the PC, disconnect USB cable

4. Select Import in the project le option in System Settings

5. Select your project le, select Import

Exporting project le from a VWA

1. Select Export in the project le option in System Settings

2. Select the le type

3. Retrieve the project le with PC

4. Save or edit the project le as needed

GPS and Time Zone

The integrated, non-survey grade GPS is used to update the internal clock and provide approximate
location data for reports.

Select System Settings to adjust the GPS time to your location or turn o the GPS. The time can be
manually set when the GPS is turned o. Daylight Saving Time can be applied as needed.

!

11

VSPECT Measurement

VSPECTTM provides the best vibrating wire measurement available. Sensor frequency is easily identied while ltering out environmental and electrical noise that aects the quality of other vibrating wire readers.
VSPECTTM provides measurement diagnostics to understand sensor response, installation quality, and identify incorrect wiring or damaged sensors.

Output and Diagnostics

Sensor Frequency1 (Hz)

Frequency is the basic measurement from a vibrating wire sensor. The frequency can be
converted into engineering units (pressure, displacement, etc.) and is identied as the largest
measured amplitude signal within the frequency sweep.

Sensor Amplitude2 (mV RMS)

Signal strength from the vibrating wire sensor. Amplitude varies and is aected by the sensor
type, excitation strength (adjustable), and sensor cable length.

Signal-to-Noise Ratio

2

(unitless)

The signal-to-noise ratio is calculated as sensor signal amplitude divided by the largest noise
amplitude within the sweep frequency. A low signal-to-noise ratio indicates a weak sensor
signal or a noisy environment.

Noise Frequency

2

(Hz)

The largest amplitude noise signal within the frequency sweep.

Decay Ratio

2

(Hz)

Signal attenuation; how quickly the signal strength decreases.

Thermistor/RTD Resistance

1

(ohms)

Used to calculate sensor temperature and correct for thermal eects3.

1

Frequency and resistance are measured values

2

Diagnostic values used to describe the quality of the frequency measurement

3

The VWA measures the vw sensor temperature (when present); post processing is required for thermal and

barometric corrections. An automated data acquisition system (ex. CR6) with an integrated barometer can
apply temperature and pressure corrections.

Warning Thresholds

Measurement warning thresholds can be set in Measurement Settings. Thresholds provide a
warning for questionable measurements (incorrect wiring or damaged sensors). When a threshold is
triggered, the alarm can be selected to display a brief list of eld troubleshooting tips.

Amplitude

The default is 0.10 (mV RMS), intended to identify weak signals
for additional review.

Signal-to-Noise Ratio

The default is 5.0 (unitless), intended to identify extreme noise

environments for additional review.
Data records normally when a threshold is triggered. It is the responsibility of the user to exercise
engineering judgment with thresholds, graphs, and additional diagnostics to determine if the
measurement is acceptable.

Note: A frequency sweep excites frequencies within the expected frequency response

range of the sensor. See the sensor manual for an expected frequency operating range.

Measurement Graphs

The following two sets of graphs illustrate the use of VSPECT

TM

to identify a sensor signal in a quiet
and noisy environment. Both graphs were created from VWA reports using the same sensor. Fig. 1
was measured in an electrically quiet environment, while Fig. 2 was measured in an electrically noisy
environment (AC power) similar to what can be seen in a eld environment (power lines, motors,
radio signals, etc.). The time series on Fig. 1 shows a relatively clean signal that is more clearly
identied on the frequency spectrum . The time series on Fig. 2 shows the inuence of
the noise . Vibrating wire readers that only use the time series to determine the frequency
may report an incorrect frequency as a result of noise. The frequency spectrum (VSPECT

TM

) lters the
noise and easily identies the sensor signal . VSPECTTM provides noise immunity by correctly
identifying the sensor signal and ignoring the inuence of electrical noise that plagues
time-domain-based vibrating wire readers.

21 The Frequency Spectrum graph shows signals with respect to frequency (VSPECT

TM

)
22 The sensor signal is determined as the largest signal within the frequency sweep
23 The Time Series graph shows raw signals observed with respect to time
24 A time series with minimal noise inuence
25 The frequency sweep is shown as the white area on the graph, only signals within the

frequency sweep will be considered as a possible sensor signal
26 Noise is identied and ignored
27 A sensor signal is easily identied even when noise is present in the measurement
28 A time series with observable noise
29 Noise in the time series (this is what confuses non-VSPECT

TM

devices)

25

21

22

23

24

25

26

27

28

29

24

22

21

28

29

28

26

27

30

33

34

32

31

35

36

37

30 31

32

WARNING: A factory reset deletes
all data.

2

Figure 1: VW Signal Figure 2: VW Signal With Noise