Campbell VWIRE 305 User manual

Revision: 11/2020
Copyright © 2019 – 2020
Campbell Scientific, Inc.

Table of contents
1. Introduction 1
2. Precautions 1
3. Initial inspection 1
4. Quickstart 2
4.1 Equipment 2
4.2 Procedure 3
5. Programming quickstart using DVWToolbox 6
6. Overview 7
6.1 Input channels 7
6.2 Dynamic sample rates 8
6.3 Static measurement 8
6.4 Embedded thermistor or RTD 8
6.5 Rainflow histograms 9
6.6 Diagnostics 9
6.7 Data use 9
7. Specifications 9
7.1 Vibrating wire – specifications 9
7.2 Temperature – specifications 10
7.3 Module 10
7.3.1 Communications 10
7.3.2 System 11
7.3.3 Power requirements 11
7.3.4 Compliance 11
7.3.5 Physical attributes 11
8. Installation 11
8.1 Install driver for computer connection 12
8.2 Operating systems 12
8.3 Configuring VWIRE 305 12
8.3.1 Configuring using DVWToolbox and LoggerNet 13
8.3.2 Configuring with the CPIAddModule() instruction 13
Table of Contents - i

8.3.3 Configuring with Device Configuration Utility 13
8.3.4 Configuring with CPIStatus table 14
8.4 Data logger connection 14
8.5 Connecting multiple GRANITE Measurement Modules 15
8.5.1 Daisy-chain topology 15
8.5.2 Star topology 16
8.6 Power connection 16
8.6.1 Power-up sequence 17
8.7 Earth ground connection 17
8.8 Mounting in an enclosure 17
8.9 Field installation 19
8.9.1 Field installation equipment 19
8.9.2 Field installation procedure 20
9. Operation 22
9.1 VWIRE 305 sample rate 22
9.2 VWIRE 305 settings 23
9.3 VWIRE 305 outputs 28
9.4 Connections 31
9.4.1 Sensor connections 31
9.4.2 CPI network bit rate 32
9.5 Analyzers and channel numbers 33
9.6 Data logger program 33
9.6.1 Program code 34
9.6.1.1 Pipeline mode 34
9.6.1.2 VWIRE 305 programming 34
CDM_VW300Config() 34
CDM_VW300Dynamic() 34
CDM_VW300Static() 34
CDM_VW300RainFlow() 35
RainFlowSample() 35
CPISpeed() 35
CPIAddModule() 35
9.7 Data quality 35
9.7.1 Amplitude warning flags 36
9.7.2 Diagnostic codes 36
9.7.3 DVWToolbox errors 37
9.7.4 Excitation strength 38
Table of Contents - ii

9.7.5 Frequency filters 38
9.7.5.1 Harmonics 39
9.7.5.2 Estimated frequency range 39
9.7.5.3 Actual frequency range 39
Matching estimated and actual frequency ranges 40
9.7.6 Frequency warning flags 41
9.7.7 Sample rate and noise performance 41
9.7.8 Standard deviation 41
9.8 Sensors 42
9.8.1 Sensor basic design features 42
9.8.2 Basic measurement of the sensor 42
9.8.3 Vibrating wire length and tension 42
9.8.4 Sensor output frequency range and maximum sample rate 43
9.8.5 Temperature sensor 43
9.9 Status of input channels and sensors 45
10. Troubleshooting 45
10.1 CPIStatus table 46
10.2 COMM status LED 47
10.3 CPI port LEDs 47
10.4 Replacing a GRANITE measurement module 47
11. References and attributions 48
Appendix A. VSPECT measurement theory 49
Appendix B. Vibrating wire digits conversion 50
Appendix C. Calculating vibrating wire measurement error 52
C.1 Error example: Geokon strain gage 52
C.2 Error example: DGSI embedment strain gage 53
C.3 Error example: DGSI spot-welded strain gage 53
C.4 Error example: Geokon 4420 crack meter 54
C.5 Error example: DGSI piezometer 52611099 54
Appendix D. Measuring thermistors and PRTs 55
D.1 Converting PRT resistance to temperature 55
D.2 Converting thermistor resistance to temperature 55
D.2.1 Thermistor measurement accuracy and resolution 56
Table of Contents - iii

1. Introduction
Designed around Campbell Scientific’s VSPECT™ measurement technology, the VWIRE 305
Dynamic Vibrating Wire VSPECT Analyzers measure vibrating wire sensors at rates up to 333.3 Hz
with high accuracy. You can use an analyzer without a data logger in a bench test, or one or
more analyzers with a Campbell Scientific data logger in a field installation.
This manual discusses the use of the VWIRE 305 with the following products, which are sold
separately:
lWall Charger 12 VDC 800 mA Output, 100-240 VAC
lCPI Network Kit
lGRANITE data logger
lLoggerNet data logger support software
2. Precautions
lREAD AND UNDERSTAND the Safety (p. 1) section at the front of this manual.
lWARNING:
oProtect from over-voltage
oProtect from water
oProtect from ESD (electrostatic discharge)
lIMPORTANT: Maintain a level of calibration appropriate to the application. Campbell
Scientific recommends factory recalibration of the VWIRE 305 every three years.
3. Initial inspection
lThe VWIRE 305 ships with the following:
oGRANITE Parts Kit (1)
lInspect the packaging and contents for damage immediately. File damage claims with the
shipping company.
VWIRE 305 1

lCheck packaging materials for all products. Check model numbers, part numbers, product
descriptions, and cable lengths against shipping documents. Model or part numbers are
found on each product. Cable numbers are normally found at the end of the cable that
connects to the measurement device. Check that expected cable lengths were received.
Contact Campbell Scientific immediately if you find any discrepancies.
lCheck the operating system version in the VWIRE 305, and the data logger. Update as
needed. See Operating systems (p. 12).
4. Quickstart
This procedure will get the VWIRE 305 set up to make measurements before connecting it to a
GRANITE data logger. This procedure, makes real-time measurements of vibrating wire sensors. It
does not store data (storing data requires an attached data logger).
4.1 Equipment
lVibrating wire sensor
lVWIRE 305 analyzer
lPower supply (Wall Charger 12VDC 800mA Output, 100-240VAC 50 60Hz, 6ft Cable is used
in this procedure)
lUSB cable
lComputer
lDVWToolbox software
VWIRE 305 2

The following figure shows a general schematic of connections:
FIGURE 4-1. General schematic
4.2 Procedure
1. Install DVWToolbox software on the computer. The DVWToolbox installation also installs
USB drivers for the VWIRE 305.
2. Connect the sensors to the VWIRE 305 (FIGURE 4-2 (p. 3) and FIGURE 4-3 (p. 4)). For
further guidance on connecting sensors, see Sensor connections (p. 31).
FIGURE 4-2. Three-wire sensor connection schematic (no embedded thermistor)
VWIRE 305 3

FIGURE 4-3. Five-wire sensor connection schematic
3. Connect the power supply to the VWIRE 305 power connector as shown.
FIGURE 4-4. Opening the power connector terminals
4. Plug in the power supply. The VWIRE 305 COMM Status light flashes yellow. Channel
Status lights may flash or remain dark.
5. Connect the USB cable between a standard computer USB port and the VWIRE 305USB
port.
VWIRE 305 4

6. Open DVWToolbox. A window similar to the following figure appears:
7. In the Com Port list, select CDM-VW300 (COMn).
The Com Port box displays CDM-VW300 (COMn). Your COMn number may differ from
that shown.
8. Connect
DVWToolbox and the VWIRE 305 connect and the button at lower left will show
Disconnect.Device Type,Serial Number,Device Name, and CPI address at lower center are
active. Depending on the state in which the VWIRE 305 was last used, channels may or may
not be enabled.
9. Check the Enable box for channels to which sensors are connected. If the correct channels
are selected, a green Channel Status flash indicates the sensor attached to that channel is
working. Lights of disabled channels are dark. For other flash combinations, see Status of
input channels and sensors (p. 45).
VWIRE 305 5

The main DVWToolbox window will look similar to the following figure:
lIf a sensor does not have a temperature sensing element, the value in the Static
Thermistor column will be negative (Channel 1).
lReasonable values in the Dynamic Frequency and Static Frequency columns indicate
the sensor outputs a vibrating wire signal. Check the values against the manufacturer
provided documentation to see if sensor output is within the correct frequency
output range.
lThe absence of information icons indicates the VWIRE 305 detects no
measurement faults. If you see an information icon, see DVWToolbox errors (p. 37).
10. For more information on adjusting Sample Rate, enabled channels, and Frequency
Boundaries see VWIRE 305 settings (p. 23), and VWIRE 305 outputs (p. 28).
5. Programming quickstart
using DVWToolbox
Campbell Scientific DVWToolbox is an easy way to generate a simple CRBasic program for your
Campbell Scientific data acquisition system.
VWIRE 305 6

1. Configure the VWIRE 305 for measurements, see Quickstart (p. 2).
2. Select CRBasic Code then Save... and select the data logger you will be connecting the
VWIRE 305 to.
3. By default, the CRBasic program will be saved in C:\Campbellsci\DVWTool.
6. Overview
Vibrating wire sensors measure strain, load, tilt, inclination, temperature, pressure, extension, and
crack movement. Measurements are stable and accurate, and sensors often survive a long time in
harsh conditions. However, the conventional technology has two problems: sensors cannot be
measured rapidly and, over a long time, sensor signal strength may be diminished.
The dynamic VSPECT measurement technology used in the VWIRE 305 overcomes these
problems and yields measurements with superior precision and noise immunity.
Quickstart (p. 2) includes simplified procedures that give a good orientation of the equipment
and software. There are nuances to the VWIRE 305 that can nullify the validity of measurements,
so you should review this entire manual before collecting actionable data.
6.1 Input channels
The VWIRE 305 is an eight-channel module (FIGURE 6-1 (p. 8)). Each removable terminal strip
measures two channels, and each channel measures one vibrating wire sensor and one
embedded thermistor or RTD. All channels are measured simultaneously. Multiple modules can
be connected to the data logger using the CPI bus. Use the CPI calculator at
www.campbellsci.com/downloads/cpi-calculator to estimate the usage and capacity of a CPI
network. To avoid skipped scans and frame errors with a VWIRE 305 network, the CPI bus load
should not exceed 75%.
VWIRE 305 7

FIGURE 6-1. VWIRE 305
6.2 Dynamic sample rates
The VWIRE 305 makes dynamic measurements at 50, 20, 10, 5, or 3 mS (20, 50, 100, 200, or 333
Hz) depending on the resonant frequency. See Table 9-1 (p. 23).
6.3 Static measurement
As part of the dynamic measurement, the VWIRE 305 makes a static measurement at 1 Hz. The
VWIRE 305 uses this measurement to get fine resolution in the dynamic-frequency
measurements. The static measurement also helps detect when a noise frequency that is near the
resonant frequency is affecting the dynamic measurement.
WARNING:
The program scan interval must be 50, 20, 10, 5, or 3 mS (20, 50, 100, 200, or 333 Hz) and
CDM_VW300Static() must be called conditionally (using TimeIntoInterval()) at a
1 second interval (1 Hz). TimeIntoIntervals other than 1 second for static data may lead to CPI
bus or data logger errors.
Additionally, CDM_VW300Dynamic() must be included in the main program scan.
6.4 Embedded thermistor or RTD
Vibrating wire sensors often have an embedded thermistor or RTD that measures the temperature
of the sensor for compensation of thermal effects on the vibrating wire measurement. The VWIRE
305 measures this sensor at 1 Hz.
VWIRE 305 8

6.5 Rainflow histograms
Fatigue monitoring of large structures often uses rainflow histograms. The VWIRE 305 calculates
histograms using the rainflow algorithm developed by Matsuishi and Endo (1968).
6.6 Diagnostics
The following diagnostic data are output with each dynamic measurement. You can use these
data to evaluate measurement quality:
lExcitation level
lLow-frequency and high-frequency warnings
lLow-amplitude and high-amplitude warnings
lStandard deviation
6.7 Data use
Campbell Scientific does not make recommendations about how to interpret or use vibrating
wire data, nor does it endorse the use of any specific manufacturer’s sensors. Examples given in
this manual are for educational purposes only. Consult competent and authoritative sources for
guidance in selecting sensors and interpreting vibrating wire data.
7. Specifications
All Standard Duty (SD) VWIRE 305 units meet electrical specifications in a temperature range of
-40to 70°C, non-condensing environment. Extended Duty (XD) units are tested over an
extended temperature range of -55to 85°C. Recommended calibration interval is every three
years.
7.1 Vibrating wire – specifications
VSPECTTechnologyPatents: U.S. Patent No. 7,779,690
U.S. Patent No. 8,671,758
Dynamic vibrating wire
measurement rate: 20, 50, 100, 200, or 333.3 Hz. Depends on resonant frequency of
the gages. See Table 9-1 (p. 23).
VWIRE 305 9

Accuracy: ±(0.005 % of reading + effective measurement resolution)
Input resistance: 5 kΩ
Excitation voltage
Range: 0 to ±3 V (6 V peak-to-peak)
Resolution: 26 mV
Sensor resonant frequency
output range: See column three of Table 9-1 (p. 23).
Effectiveresolution
(precision): 0.005 to 0.45 Hz RMS, depending on scan rate. See column five of
Table 9-1 (p. 23).
Sustained input voltage on
measurement terminal
without damage: –0.5 to 7.1 V
7.2 Temperature – specifications
Temperaturemeasurement: 24-bit resistance measurement of thermistor or RTD embedded in
the vibrating wire sensor.
Rate: 1 Hz
Accuracy: 0.15 % of reading. Does not include cable resistance error, or
thermistor or RTD error.
Resolution: 0.002 Ω RMS @ 5 kΩ
Bridge resistor: 4.99 kΩ 0.1 %
Excitation voltage: 1.5 V
7.3 Module
7.3.1 Communications
CPI: RJ45 interface to Campbell Scientific data loggers, sensors, and
GRANITE Measurement Modules.
USB: USB micro-B device only, 2.0 full-speed 12 Mbps, for computer
connection.
VWIRE 305 10

7.3.2 System
Processor: Renesas RX63N (32-bit with hardware FPU, running at 96 MHz)
Memory: 2 MB SRAM
7.3.3 Power requirements
Voltage: 10 to 32 VDC
Typical Current Drain: 190 mA @ 12 VDC
110 mA @24 VDC
7.3.4 Compliance
View EU Declarations of Conformity at www.campbellsci.com/vwire305.
7.3.5 Physical attributes
Dimensions: 20.3 x 12.7 x 5.1 cm (8.0 x 5.0 x 2.0 in); additional clearance
required for cables and wires
Weight: <1 kg (2.0 lb)
Operating Temperature
Standard Duty (SD): –40 to 70 °C
Extended Duty (XD): –55 to 85 °C
8. Installation
Preconfigure and test stations in an indoor location before doing the field installation.
After installing a field station, wait around long enough to confirm that good measurements are
being made, that data are collected to the GRANITE data logger, and that data from the
GRANITE data loggercan be collected to a computer.
8.1 Install driver for computer connection 12
8.2 Operating systems 12
8.3 Configuring VWIRE 305 12
8.4 Data logger connection 14
8.5 Connecting multiple GRANITE Measurement Modules 15
VWIRE 305 11

8.6 Power connection 16
8.7 Earth ground connection 17
8.8 Mounting in an enclosure 17
8.9 Field installation 19
8.1 Install driver for computer connection
Installing the VWIRE 305 may require a connection to a computer. Install the device driver before
plugging the VWIRE 305 into your computer for the first time. You will need the device driver
properly installed before you can connect to the VWIRE 305 via USB. To install the device driver
using the Device Configuration Utility, select GRANITE >VWIRE 305. Click the Install the USB
driver link and follow the prompts.
TIP:
Driver installation is optional for computers running Windows 10 and later.
8.2 Operating systems
Campbell Scientific posts OS updates at www.campbellsci.com/downloads when they become
available. Before deploying instruments, check operating system versions and update as needed
to the most recent version. Use the Device Configuration Utility and follow the procedures on the
Send OS tab.
NOTE:
For best performance, use the most recent operating system for each device.
8.3 Configuring VWIRE 305
The VWIRE 305 arrives ready to be connected to a system. Device configuration is only required
when multiple GRANITE Measurement Modules are connected to a single data logger. Each
module must have a unique address. Set a unique device name for further distinction between
GRANITE Measurement Modules.
Configure the VWIRE 305 using one of four methods: through DVW Toolbox, the
CPIAddModule() program instruction, Device Configuration Utility software, or the CPIStatus
table.
VWIRE 305 12

8.3.1 Configuring using DVWToolbox and LoggerNet
Modules are configured when connected to DVW Toolbox. DVW Toolbox sets the module CPI
address to 1 and sets up the measurement channels.
For more information see Quickstart (p. 2)
8.3.2 Configuring with the CPIAddModule() instruction
To configure a VWIRE 305 within a program, use the CPIAddModule() instruction. A separate
instruction is used for each device. The CPIAddModule() instruction overrides settings
entered by other means, such as Device Configuration Utility or the CPIStatus table.
CPIAddModule(CDMType, CDMSerialNo, CDMDeviceName, CPIAddress)
The data logger creates an internal list of CPI modules from each CPIAddModule()
instruction. Modules added to the CPI bus will be checked against this list and reconfigured
accordingly.
NOTE:
The CPIAddModule() instruction overrides changes made through Device Configuration
Utility or the CPIStatus table.
8.3.3 Configuring with Device Configuration Utility
Install the device driver before connecting the VWIRE 305 to a computer. This is optional for
Windows 10, or later, operating systems.
1. Open Device Configuration Utility.
2. Under Device Type, select GRANITE >VWIRE 305.
3. Carefully review the Connect Instructions text provided on the right.
4. With the USB device driver installation complete, connect the supplied USB cable between
the USB port on your computer and the USB port on the VWIRE 305.
5. Apply 9.6 to 32 VDC to the power terminals on the device.
6. Click the browse button next to Communication Port.
7. Select the port labeled VWIRE 305.
8. Click OK.
9. Click Connect then OK to avoid conflicts.
VWIRE 305 13

10. Set the Device Name (optional) and the CPI Address.
a. Device Name is a user-editable field to set a unique name to the VWIRE 305.
b. CPI Address specifies the address of the VWIRE 305. Each GRANITE Measurement
Module connected to the same data logger must have a unique address. By default,
the VWIRE 305 uses a CPI address of 1. Allowable addresses are 1 through 120.
11. Click Apply to save your changes.
8.3.4 Configuring with CPIStatus table
When a GRANITE Measurement Module is used in a program, the data logger adds a CPIStatus
table to display current CPI information. View the CPIStatus table in the LoggerNet Connect
screen, or Device Configuration Utility Data Monitor tab. Information about each module
included in the data logger program or connected to the CPI bus appears in the CPIStatus table
within the ModuleInfo() array. Information is shown in the following order:
GRANITE Measurement Module Type, Serial Number, Device Name, CPI Address,
Activity, CDM OS Version
NOTE:
CDM OS version will be the last element in the ModuleInfo() array for VWIRE 305 modules
with OS version 6 or newer.
Within the ModuleInfo() array index string, the Device Name and CPI Address fields can be
edited. This provides a way to rename and readdress a VWIRE 305 through Campbell Scientific
software without editing the CRBasic program or connecting directly to the USB port.
See CPIStatus table (p. 46) for additional information.
8.4 Data logger connection
VWIRE 305 devices communicate with a data logger through a CPI port. Each VWIRE 305 ships
with a 6-inch RJ45 cable for this connection, though any CAT5e, or better, RJ45 cable can be
used. To allow daisy-chaining, two CPI ports are available on the VWIRE 305. Either can be used
for connection to a data logger.
The CPI port on VWIRE 305 connects directly to the CPI port on a GRANITE data logger module,
CR6 and the CR1000X.
VWIRE 305 14

8.5 Connecting multiple GRANITE
Measurement Modules
The CPI bus, which handles the communications between the data logger and GRANITE
Measurement Modules, can accept addresses 1-120. Multiple GRANITE Measurement Modules
may be connected to a single data logger using a daisy-chain or star topology. In both network
configurations, as total cable length increases, the maximum possible bit rate decreases.
Therefore, in networks with long cable lengths, it may be necessary to use the CPISpeed()
instruction to decrease the CPI network bit rate from its default 250 kbps. Limitations on cable
length and bit rate are discussed further in CPI network bit rate (p. 32) and listed in Table 9-4 (p.
33).
8.5.1 Daisy-chain topology
In a daisy-chain topology, GRANITE Measurement Modules are connected one after another, as
shown in FIGURE 8-1 (p. 15).
FIGURE 8-1. Multiple GRANITE Measurement Modules connected in a daisy-chain
topology
For best performance, CPI terminators (supplied in GRANITE Network Kit) are usually installed in
the open CPI ports at both ends of a daisy-chain network. But a half-terminated bus is also
allowed by using only the resistors at the data logger end of the network. For more information
see:https://s.campbellsci.com/documents/us/technical-papers/cpi-bus.pdf.
VWIRE 305 15

8.5.2 Star topology
A star topology uses a passive RJ45 hub, such as the HUB-CPI, to connect multiple GRANITE
Measurement Modules. An illustration of this is shown in FIGURE 8-2 (p. 16).
NOTE:
Do not use a CPI-terminator with this configuration.
FIGURE 8-2. Multiple GRANITE Measurement Modules connected in a star topology
8.6 Power connection
Connect the power supply to the removable Power connector on the side of the VWIRE 305.
Power supplies providing voltages from 9.6 to 32 VDC may be used.
lWhile the input power requirements of Campbell Scientific instruments vary, there is one
constant – they all run on 12 VDC. To keep things simple, we only discuss the use of 12 VDC
power supplies in this manual.
lDo not connect live wires to an instrument. All connections discussed assume dead wires,
so switch off power supplies before making connections.
lDouble check the polarity of connections before switching on power supplies.
Open the power connector by inserting a screwdriver into the slots shown in FIGURE 8-3 (p. 17).
When the screwdriver is pushed in far enough, the orange terminals will open and remain open
until the screwdriver is removed. The power connector includes two positive (+VDC) terminals
and two negative (–VDC) terminals to allow for daisy-chaining power supplies. Terminals of the
same type open and close together. Insert the positive wire from the power supply into a +VDC
terminal, and insert the negative wire into a –VDC terminal.
VWIRE 305 16