Keynes Controls VibWire-201-Pro User manual

VibWire-201-Pro User Manual 1
Vibrating Wire Sensor Analyser
&
Data Recording Unit
Model VibWire-101-Pro
Manufactured by Keynes Controls Ltd
Advanced FFT Sensor Analyser
Advanced FFT Sensor AnalyserAdvanced FFT Sensor Analyser
Advanced FFT Sensor Analyser
User Pre-set VW Sensor Configurations
User Pre-set VW Sensor ConfigurationsUser Pre-set VW Sensor Configurations
User Pre-set VW Sensor Configurations
Sdi-12 & RS- 85 Communication Ports
Sdi-12 & RS- 85 Communication PortsSdi-12 & RS- 85 Communication Ports
Sdi-12 & RS- 85 Communication Ports
Data logging to micro SD memory card
Data logging to micro SD memory cardData logging to micro SD memory card
Data logging to micro SD memory card
Up to 32 gb Storage
Up to 32 gb Storage Up to 32 gb Storage
Up to 32 gb Storage
Spreadsheet Format Data Files
Spreadsheet Format Data Files Spreadsheet Format Data Files
Spreadsheet Format Data Files
Real-time Clock
Real-time ClockReal-time Clock
Real-time Clock
Daylight readable LCD display
Daylight readable LCD display Daylight readable LCD display
Daylight readable LCD display Expansion Options
Expansion Options Expansion Options
Expansion Options
- 16 x Wire Inputs
- 16 x Wire Inputs - 16 x Wire Inputs
- 16 x Wire Inputs
- 32 x 2 Wire Inputs
- 32 x 2 Wire Inputs - 32 x 2 Wire Inputs
- 32 x 2 Wire Inputs
Part No: VibWire-201-Pro
Manufactured by KEYNES CONTROLS LTD
Tel: [phone]
E-mail: [e-mail]
Precision Temperature Readings
Precision Temperature ReadingsPrecision Temperature Readings
Precision Temperature Readings

VibWire-201-Pro User Manual 2
Features
Lightweight, Portable & Rugged
Compatible with most manufactures vibrating wire sensors
Real-time displays Freq (Hz), Digits (Hz
2
/1000), SI-Units, Spectra
FFT Spectral based algorithms for interference free measurements
Auto-resonance excitation 400 - 15 K Hz range - minimises sensor stress
Fully configured sensor operations
Large data storage - 100 million readings - SD Flash Cards to 32 Gb
Fast data recording - 1 sec to 1 hour logging intervals
No Vibrating Wire Sensor Prior operating conditions required
Expandable to 32 channels
SDI-12 and RS-485 ports for remote network connection
Optional radio interfaces for cable free operations
Firmware up gradable device - load software revisions with factory return
Copyright 2016-2017 Keynes Controls Ltd
No part of this manual can be reproduced in part, or in whole
without the permission of Keynes Controls Ltd.
©
Benefits
Out the box solution for vibrating wire sensor measurements
Daylight readable LCD Display
Provides superior measurements by automatically reducing incorrect readings caused by noise sources
Customised FFT-based algorithm ensures readings are accurate and free from interferences
Real-time Sensor Spectra Display
No special cables or connectors required
No programming experience required to interface to 3rd party loggers and data acquisition systems..
Interfaces up to 32 channels using the MUX-16/32 Expansion unit.
High resolution—less than 0.001 Hz (industry standard is 0.1 Hz)
Low power consumption - Uses readily available AA battery life - 24 Hours continuous use
Suitable for laboratory testing and field measurement applications
Precision temperature and frequency measurements from vibrating wire sensors
Works with all RTD-temperature sensors regardless T0 resistance - 3 K, 10K etc
Free Data Storage and Display Applications Software -
MUX-16/32 Expansion Unit USB-SDI12-Pro Media Converter USB-485-Pro Media Converter
Additional items commonly used with the VibWire-201-Pro Unit
This device is used to expand the number of sensor inputs
that can be used by the VibWire-201-Pro from a single
channel to 32 inputs.
This device can be powered directly from the
VibWire-201-Pro for stand-alone measurements.
This device is used to connect the VibWire-201-Pro to a
Windows PC remotely across the SDI-12 digital network.
The USB-SDI12-Pro can be used to power the VibWire-
201-Pro for fixed monitoring applications
The device supports all of the Keynes Controls SDI-12
sensor and interfaces, including many 3rd party devices.
The USB-SDI12-Pro isolates the network devices from the
Windows PC USB port and protects it against possible
damage caused by sensor failures.
This device is used to connect RS-485 based intelligent
devices including the VibWire-201-Pro a Windows PC.
The device not only can power sensors on the network,
but also isolates the PC USB port from any possible device
failure in order to prevent damage to the host PC.
The device supports all of the Keynes Controls RS-485
sensor and interfaces, including many 3rd party devices.

VibWire-201-Pro User Manual 3
Page Number Description
5 Hardware Features / Controls and Ports
Auto-timeout / Real-time Clock.
Factor Default Settings Reset
6 Quick User Guide - Default Thermistor part numbers - Real-time Results - Adjusting the display
VW Sensor Installation.
7 Fitting Batteries - Battery Life - MUX-16/32 Expansion Port - Initial Start-up Screen -Low Battery Effects - Setting the Real-time Clock
Saving New Parameters - Adjusting the Time
8 Real-time Results -
Initial Start-up Display - Frequency Results Display - Digits Results Screen - Natural Units (SI) - Spectra Display
Spectral Features.
9
Digital Network Selection
Device Port Selection - SDI-12 Network Connection - RS485 Network Connection (Using USB-SDI12-Pro or USB-485-Pro media converters)
10 Technical Specifications
Temperature Measurements - Associated Part No - Device Configuration Software - Common VW Sensor Thermistor Part Numbers
- Sources of Error - Calibration Factor Error - User Defined Stein-hart Hart Calibration Factors
- Sensor Information
11 Pre-set Sensor Configurations
- Downloading and installing device setup software - Automatically setting the real-time clock.
Pre-defined Thermistor Calibration Parameters (Steinhart-Hart Calibration factors)
Automatically setting the real-time clock.
12 Channel Expansion Options
- 16 x 4 Wire Expansion - 32 x 2 wire expansion
13 Number of Channels
- Mux-16/32 Expansion Unit Configuration Options - MUX Channel Selection Menu Options
Data Recording - Data Recording Options - Data Recording Menu System
14 Program Commands for scanning MUX-16/32 in 32 x 2 Wire mode (3rd party loggers )
Program Commands for scanning MUX-16/32 in 16 x 4 Wire Mode
- Switching between 2 and 4 Wire Mode Operations under SDI-12 Commands
15 Frequently Asked Questions
- VW201-Pro want communicate with 3rd party logger - Network ID Number - How fast can the VibWire-201-Pro make a measurement
- Where to download the Q-LOG Software - How to make a measurements using a PC without any programming experience
- MUX-16/32 Connection Options to the VibWire-201-Pro
16 Sensor Configuration Example - Piezometer
Temperature Compensated Calibration Factors - Results in Natural (SI) Units
Process Option setting - Pre-set Sensor Configuration Settings - Simplified Calibration Factors
17 Sensor Configuration Example - Piezometer
Temperature Compensated Calibration Factors - Results in Natural (SI) Units
Process Option setting - Thermistor Type (VW201cal software)
Pre-set Sensor Configuration Settings (VW201cal software)
Simplified Calibration Factors
18 Q-Log - Quick User Guide
Factory Default Settings -Sample Rate Options
- Logging Configuration Window - Scanning for Devices
External Power Supply -Device identifier strings
PC Data Acquisition - Start data recording
19 Technical Specifications
20 Examples Of Using RS-485/SDI-12 Commands
Changing the ID Number (address) - Start a measurement for Instrument on a network
Isolated Power Source
Diagnostics
21 Data Record to Flash Memory Card
Removing The Memory Card
Storing the menu option
Default Sample Rates
External Power Supply
Isolated USB Media Converters
22 Worked Example - Spot Welded VW Strain gauge
Data into engineering units - simplified formula
23 Temperature Calibration Factors (VW201cal software)
Adding a new thermistor type - Calibration parameters and what they mean - Sample Calibration Factors
24 PC based Water Level Recording with Barometric Correction.
Device USB Configuration Port - Connection to a Data Logger
25 Temperature Measurements
Factory Set Steinhart Hart Calibration Factors
Testing the temperature measurements
- 22 Deg C fixed point - 3.3 K Ohm temperature test resistor
- 52 Deg C fixed point - 1 K Ohm temperature test resistor
26 Sensor Problems and Diagnostics
Sensor Operating Characteristics
27 Free Standing Strain Gauge
- VW strain gauge - Pre-tension gauge mounted onto a structure
- VW strain gauge - Failed or loose weld
29 APPENDIX-A Menu System Summary
32 APPENDIX-B Sample Calibration Data Sheets

VibWire-201-Pro User Manual 4
Figures Description
Fig 1 Hardware Features
Fig 3 Initial Start-up Screen - no sensor connected
Fig 7 & 8 Sensor Installation
Fig 9 Adjust results display screens
Fig 10 Fitting batteries
Fig 12 Setting the real-time clock
Fig 14 - 17 Results displays
Fig 18 - 19 VW sensor spectra
Fig 20 - 21 Device Port Selection
Fig 22 SDI-12 network connection - USB-SDI12-Pro Media Converter
Fig 23 RS-485 network connection - USB-485-Pro Media Converter
Fig 24 - 25 VW201cal Software - Calibration Factors Entry Window
Fig 26 32 x 2 Wire Expansion with the MUX-16/32 Unit
Fig 27 16 x 4 Wire Expansion with the MUX-16/32 Unit
Fig 28 MUX-16/32 Control Menu System. Set number of channels to scan.
Fig 29 Data Recording Menu System
Fig 31 MUX-16/32 Output Port Connections for 32 x 2 Wire Mode.
Fig 32 MUX-16/32 Output Port Connections for 16 x 4 Wire Mode.
Fig 33-35 32 x Frequency / 32 x Temperature / 16 x 4 Expansion Unit Wiring Options.
Fig 39 Select individual MUX-16/32 Channel Menu System
Fig 41 VW201cal Software - Example Calibration (Frequency) factor configuration Window.
Fig 43 Preset Sensor selection Menu System
Fig 45 SDI-12 port pin-outs - USB-SDI12-Pro and VibWire-201-Pro
Fig 46 Q-LOG Configuration Window - Data Logging - PC Port Network Type Selection.
Fig 48 Scanning for Devices - Q-Log Window.
Fig 49 Q-LOG Devices List Window
Fig 50 Q-LOG Start Data Acquisition Window
Fig 53 External Power Supply
Fig 54 Recording Interval Menu Options
Important Figures
Keynes Controls Ltd has an on-going policy of design review and reserves the right to amend
the design of their product and this instruction manual without notice
Product Changes
VibWire-201-Pro demonstrating the ability
to calculate and display a real-time
vibrating wire sensor spectra.

VibWire-201-Pro User Manual 5
Hand Held VW Logger Unit with FFT Analyser
Hand Held VW Logger Unit with FFT Analyser Hand Held VW Logger Unit with FFT Analyser
Hand Held VW Logger Unit with FFT Analyser
Menu-In &
Power On/Off
Button
MUX-16/32 Control Port
Sensor Port
Compatible with the
VW101 & VW108 units
RS-485 network port
SDI-12 network port
Back light - LCD Screen
Options for High , Low, Off.
4 Wire Sensor Inputs + Earth
Spring Terminal Post Connectors
Carbon fibre reinforced
ABS plastic enclosure
Rubber protective
boot cover
Day Light Readable LCD Display
The LCD display is clear to read in most lighting conditions. A
back light is available for low level light environments. Three
levels or display brightness can be ‘User’ assigned.
Real-time Clock
Temperature compensated real-time clock accurate to 50 ppm
/ Deg C.
User Defined Sensors - 20 options
Use the Windows Configuration software to assign
sensor details.
Frequency
Port
Temperature
Port
Earth
Power On
To power on the VibWire-201-Pro unit, hold and press the On/Off
button for 2 seconds. The device will initiate and start a measurement
operation.
The device will initialise using the last defined senso r.
Power Off
Hold and press the On/Off button and the device will power off .
The 4 wire sensor port mounted at the bottom of the instrument is
used a general sensor test port. Bare sensor wires can be simply
connected directly into the spring terminal posts.
Menu-InMenu-Out Down Up
Menu Control Buttons
Use the Menu-In and Menu-Out buttons to select the different
menu systems.
User the ‘Up’ and ‘Down’ menu keys to select the menu items.
Powering on the Unit
Press and hold for 2 seconds the ‘Menu Out’ button. The device will
power on and the ‘Start-up Screen will be displayed. Repeat the
operation to power off the device.
Menu-Out
On/Off Button
Ethernet Port
Micro-USB Port
(Type B)
SDHC flash memory
card slot.
Ethernet Port
The Ethernet port is currently not used in the VibWire-201-Pro and has been added for future expansion.
Micro-USB Port (Type B)
The micro-USB port is used to configure the VibWire-201-Pro and to download data. Use the VW201pro configuration software tool assign sensor configuration
information into the instrument.
SDHC Flash Memory
The VibWire-201-Pro supports a single SDHC memory card slot. The memory card has to be pre-formatted before use.
The maximum size memory card currently supported is 32 Gb.
Protective Case
The case for the VibWire-201-Pro is manufactured from carbon fibre reinforced
ABS plastic. This makes the case highly safe from accidental damage.
The rubber boot prevents provides additional protection from the wear and tare
of site work. A rear stand enables the device to free stand while in operation.
Factory Default Setting Reset
Select the ‘Reset Defaults’ option shown below to reset the device to its factory
settings. The image below shows the menu operations required to undertake
this task.
Fig-1
Fig-2
Automatic Time-out
The VibWire-201-Pro will power down automatically after 30 minutes of un-
attended operation, unless configured to make measurements.
Hardware Features
System
Set Time and Date
Backlight
Reset Defaults
Info
Menu-In
Menu-In
Frq
Dig
Val
Frequency
Selected Sensor
Hz
Dg
SI
Res
Tem
6
2534.86
2534.86
6424.95
2016 -01-20 08:40::1 7
3003.56
24.89
992.28
Hz
Ohm
C
Main Menu
Sensor No
Logger
Multiplexer
Remote
System
Speaker ON/OFF
Signal connection Posts
Digits = Frequency
2
1000
(Hz
2
)
1000
Calculations
Keynes Controls use the following calculation

VibWire-201-Pro User Manual 6
Quick User Guide
The instructions shown in the Quick User Guide presumes that the batteries have
already been installed into the device and a vibrating wire sensor is ready for
testing.
The VibWire-201-Pro will operate with any sensor manufactures device.
The VibWire-201 comes pre-configured with default temperature sensor calibration
factors defined. The pre-set temperature sensor calibration factors are based on
a 3 K Ohm @ 25 Deg C device. The following sensor part numbers all use the
same calibration settings.
Default Thermistor Part Numbers
YSI 44005
Vishay 1C 3001 B3
RS Part no: 151-215
1. Power On The VibWire-201-Pro.
Press and hold the ‘Power On’ for 2 seconds.
and with no sensor connected the default
Frequency display is shown opposite.
2. Connect a vibrating wire sensor to the device
Connect a single sensor to either the 5 pin terminal block input port or directly onto the
sensor port mounted at the bottom of device using the spring loaded terminal posts..
Connect the frequency output signal from the sensor to the red and
black terminal posts.
Connect the vibrating wire sensor thermistor (temperature sensor)
to the green and yellow terminal posts.
3. Real-time Results
As soon as the vibrating wire sensor is connected to the VibWire-201-Pro then the measurements
will be displayed on the display.
A typical display screen is shown opposite.
3. Use the ‘Up’ and ‘Down’ keys to switch between Hz, Digits and Spectra.
The SI unit display remains blank until configured.
Adjusting the display
Use the keyboard ‘Up’ and ‘Down’ arrow keys to adjust the results display screens.
The display screen will be change as the
Up and Down keys are pressed.
Frq
Dig
Val
Frequency
Selected Sensor
Hz
Hz
Dg
SI
Res
Tem
Ohm
C
6
99.00
99.00
9.80
2016-01-20 08:40::17
1000001
-70.20
9.80
Default screen with no sensor attached.
Frequency
Input Signal
Connection
Thermistor
Input Signal
Connection
Frq
Dig
Val
Frequency
Selected Sensor
Hz
Hz
Dg
SI
Res
Tem
Ohm
C
6
2534.86
2534.86
6424.95
2016-01-20 08:40::17
3003.56
24.89
992.28
Menu-InMenu-Out Down Up
Digits
Frq
Dig
Val
Frequency
Selected Sensor (3) EDS-20
Hz
Dg
SI
Res
Tem
6
2534.86
2534.86
6424.95
2016-01-20 08:40::17
3003.56
24.89
992.28
Hz
Ohm
C
Digits
Selected Sensor (3) EDS-20
D
Hz
Dg
SI
Res
Tem
Ohm
C
6
6424.95
2534.86
6424.95
2016-01-20 08:40::17
3003.56
24.89
992.28
Frq
Dig
Val
FFT Sensor Spectra
Selected Sensor (3) EDS-20
Hz
Dg
SI
Res
Tem
Ohm
C
6
2534.86
6424.95
2016-01-20 08:40::17
3003.56
24.89
992.28
Frq
Dig
Val
0 1 2 3 4 5 6 10 11 12
13 14 15
7KHz
SI Units
Frequency
The results shown above are obtained using an Encardio-rite EDS-20
vibrating wire pressure sensors.
VW Sensor Installation
The VibWire-201-Pro supports full 4 wire sensor operations. The device
measures frequency and temperature from any suitable vibrating wire sensor.
Connect a Vibrating Wire sensor to the 5 pin ‘Sensor Input’ port or directly to
the spring return termination posts mounted at the bottom of the unit.
1. Connect the sensor coil to the ‘Frequency Input’ port.
2. Connect the sensor thermistor (temperature) sensor to the ‘Temperature
Input’ port.
3. Use the VW201cal.exe software to define thermistor calibration factors.
Figures 7 and 8 show how to connect a vibrating wire sensor to the device.
Earth
- VW Sensor
+VW Sensor
- Thermistor
+ Thermistor
Frequency
Signal
Coil
Thermistor
temperature
sensor
Sensor Port
Earth Frequency
Input
Temperature
Input
+-
Frequency
Signal
Coil
Sensor
Terminal
Posts
Sensors connected to the spring loaded terminal posts
Sensors connected to the Sensor Port
Up Down
Spectra
Sensor
Selected Sensor (3) EDS-20
Nat Units
Hz
Dg
SU
Res
Tem
Ohm
C
6V
992.28
2534.86
683.929
2016-01-20 08:40:17
3003.56
24.89
992.28
Frq
Dig
Val
Down Up
Use the Up and Down arrow keys
to switch between the results screens
Fig-3 Initial Start-up Screen
Fig-4
Fig-5
Fig-6
Fig-7
Fig-8
Fig-9

VibWire-201-Pro User Manual 7
Fitting Batteries
Only fit standard AA batteries in the VibWire-201-Pro.
1. Remove the battery cover from the rear of the device by simply unscrewing the securing bolts.
2. Replace the battery set in the layout shown in the image opposite.
3. Replace the battery cover and power on the unit.
The battery level indicator will show 6V when a new set of batteries has been installed See Fig 11.
Battery Life
When operating as a single channel device using a new set of batteries the VibWire-201-Pro will operate for
approximately 40 Hours continuous use.
MUX-16/32 Expansion Operations
The VibWire-201-Pro powers the MUX-16/32 expansion unit directly across the SDI-12 BUS and will reduce the
battery life of the device if used without an external power supply.
IMPORTANT NOTE
Remove the batteries from the VibWire-201-Pro should the device not be used for a long period of time.
Low Battery Level Effects
Once the battery levels falls before 4.5 V then
1. Display may not update at the correct rate and appears to flicker.
2. Measurement values can be erratic.
Once the display falls below 4.5V then the ‘Low Battery’ indicator flashes, see Figure 13 below. Should the unit
continue to operate then the display may flicker. Fit a new set of batteries.
Battery level
when a new set of
batteries are installed into the unit.
Initial Start-up Screen
++
++
--
--
AA 1.5 V Cells
Hz
Ohm
C
2016-01-20 08:40:17
3003.56
24.89
Frq
Dig
Val
Frequency
Selected Sensor (1)
99.00
99.00
9.80
9.80
Hz
Dg
SI
Res 1000000.00
Tem -70.2
6 V
2016-01-20 08:40::17
Setting the Real-time Clock
The real time clock in the VibWire-201-Pro is configured using the ‘Set Time
and Date’ menu. See Page FF section G.
The VibWire-201-Pro can be used as a stand-alone VW sensor data logger
recording measurements automatically, and also to take single shot readings
under ‘User’ control.
Measurements are stored to the flash memory card.
See Page MM for details on selecting the ‘Time and Date’ menu.
Real-Time Clock Menu System
Set Time and Date
Example
6
th
January 2016
08:25 AM 30 Seconds
Date 2016-01-06
Time 08:25:30
Date Year-Month-Day
Time Hours:Minutes:Seconds
(Time/Date Format)
Down Up
Use the Up and Down keys between ‘Date’ and ‘Time’ options.
(Selected Item Indicator)
Use the ‘Menu-Out’ and ‘Menu-In’ keys to move along the Date or Time fields.
As the keys are pressed the item indicator symbol will be displayed
under chosen item.
Menu-InMenu-Out
Date 2016-01-06
Once the parameter to adjust has been chosen then use the ‘ Up ’ and ‘ Down ’
buttons to make changes.
The ‘ Up ’ and ‘ Down ’ buttons will increment, or decrement a parameter by 1 unit
after each action.
Year
Down
Up
Date 2016-01-06
Down
Up
Month
Date 2016-01-06
Down
Up
Day
Adjusting the Date
Select Date or Time to be configured
Time 09 : 23: 06
Hours
Down
Up
Down
Up
Mins
Down
Up
Secs
Time 09 : 23: 06 Time 09 : 23: 06
Adjusting the Time
Move through each date an and time parameter in turn making adjusts as
necessary.
Saving New Parameters
Once all parameters have been set, press the button unit the
default ‘Frequency’ menu is displayed.
The new date and time values will be stored and the real-time clock settings
updated to the different menus.
Menu-Out
Hz
Ohm
C
2016-01-20 08:40:17
3003.56
24.89
Frq
Dig
Val
Frequency
Selected Sensor (1) EDV-30
99.00
99.00
9.80
9.80
Hz
Dg
SI
Res 1000000.12
Tem -70.2
Low Battery 2016-01-21 10:40::17
Date and time string will update
with the new settings.
Note
The VW201cal.exe Windows configuration software automatically sets the
time and date used by the VibWire-201-Pro to the PC clock.
Fig-10
Fig-11
Fig-12
Fig-13
Low Battery
Indicator

VibWire-201-Pro User Manual 8
Frq
Dig
Val
Frequency Hz
Hz
Dg
SI
Res
Tem
Ohm
C
6 V
834.69
834.69
696.70
2016-01-20 08:40:17
3571.73
21.07
696.70
Copyright Keynes Controls Ltd 2015
Frq
Dig
Val
Frequency Hz
Hz
Dg
SI
Res
Tem
Ohm
C
6 V
Date Time
99.00
99.00
9.80
Battery
Voltage
2016-01-20 08:40:17
100000.1
-70.20
Initial Start-up Screen
Resistance Thermistor
temperature sensor built
into a VW sensor.
Instant sensor
temperature in Deg C
Digits
Selected Sensor (4) EPP-30V
D
Hz
Dg
SI
Res
Tem
Ohm
C
6 V
Date Time
2534.86
2534.86
6424.95
Battery
Voltage
2016-01-20 08:40::17
3003.56
24.89
992.28
Digits = Frequency
2
1000
All Keynes Controls VW sensor
instrumentations uses the digits
calculation
SI Units
Frq
Dig
Val
SI Units
FFT Sensor Spectra
0 1 2 3 4 5 6 10 11 12
13 14 15
7KHz
Fundamental
Frequency
1st Harmonic
Frequency
2
nd
Harmonic
Frequency
Maximum Operating
Frequency
2534.86
6424.95
= Fundamental Frequency in Hz
= Fundamental Frequency in Digits
Fundamental Frequency
Fundamental Frequency
in Digits
(Hz
2
)
1000
The VibWire-201-Pro undertakes the spectral calculations on the incoming
vibrating sensor signal and gives the results immediately.
There are no ‘User’ configuration settings required to be assigned in order to
undertake a spectral calculation.
The largest peak is taken as the fundamental operating frequency of the sensor.
See Fig 19 opposite.
See Note 1
9.80
Real-time Results
Figures 14 below shows the default display that appears as soon as the device is powered on and with no sensor connected to an input port.
Upon connection of a sensor to the input port then the device automatically displays the frequency and temperature values.
With no sensor coil connected to the frequency input then the device defaults to 99.00 Hz.
Fig 14
Note. The example screens have been determined using a free standing
Encardo-Rite EPP-30V pressure sensor
Frequency Results - Hz
Frequency (Hz)
Digits - Hz
2
/1000
Engineering Units
Thermistor
Resistance Value
VW sensor
Temperature Deg C
Sensor Frequency (Hz)
VW Sensor - SI Unit (Hz)
VW Sensor - SI Unit (Digits)
Frequency Results - Hz
2
(Digits)
FFT Sensor Spectra
Selected Sensor
Hz
Dg
SI
Res
Tem
Ohm
C
6 V
Date Time
2534.86
6424.95
2016-01-20 08:40::17
3003.56
24.89
992.28
SI Units
VW Spectra Screen
Frq
Dig
Val
0 1 2 3 4 5 6 10 11 12
13
14 15
7KHz
Battery
Voltage
Frequency (Hz)
Digits - Hz
2
/1000
Engineering Units
Spectra (Hz)
Down
Up
All Keynes Controls VW sensor instrumentations uses the digits calculation
Digits = Frequency
2
1000
(Hz
2
)
1000
Sensor
Selected Sensor (4) EPP-30V
Nat Units
Hz
Dg
SI
Res
Tem
Ohm
C
5.2 V
Date Time
300.31
876.86
768.36
Battery
Voltage
2016-01-20 08:40::17
3984.29
18.67
300.31
Frq
Dig
Val
SI Units
VW Sensor - SI Unit
Natural Units (SI)
Once a vibrating sensor is connected to an input port the display will change
similar to that shown above.
Output value in
engineering
units.
Once the calibration factors have been set, and the process option set to ‘2’ see
Fig 24 on page 11.
Fig-15
Fig-16 Fig-17
Fig-18
Fig-19
Use the ‘Up’ and ‘Down’ arrow keys
to switch between the different
results screens.
Important Note
Selected Sensor (4) EPP-30V Selected Sensor (4) EPP-30V

VibWire-201-Pro User Manual 9
Remote Mode
Selected Sensor
D
Hz
Dg
SI
Res
Tem
Ohm
C
6
2534.86
6424.95
2016-01-20 08:40::17
3003.56
24.89
992.28
Frq
Dig
Val
Port = SDI-12
Address = 1
Measurement Count = 1032
VibWire-201-Pro
SDI-12 Network Connection
Figure 22 below shows how to connect the VibWire-201-Pro SDI-12 port to a
USB-SDI12-Pro media converter. The USB-SDI12-Pro media converter con-
nects to a Windows PC and allows measurements from VibWire-201-Pro to
displayed directly into
RS-485 Network Connection
Figure 23 below shows how to connect the VibWire-201-Pro RS-485 port to a
USB-485-Pro media converter. The USB-485-Pro media converter connects to
a Windows PC and allows measurements from VibWire-201-Pro to displayed
directly into the Q-LOG data display and recording software.
The VibWire-201-Pro acts like any other intelligent 485 device, and will operate
with any other suitable device 3rd party device on the network.
Selecting Remote Network Connections
The VibWire-201-Pro unit can connect to the SDI-12 and RS-485 networks for use in remote vibrating wire sensor measurements.
The SDI-12 and RS-485 ports enable the VivbWire-201-Pro to transmit sensor data into third party data logger and acquisition systems.
- RS-485
Gnd/0V
12 DC
+ RS-485
SDI-12
Port
Gnd/0V
12 DC
SDI-12 Data
Part No: USB-SDI12-Pro
Part No. USB-485-Pro
SDI12 Remote Port
Remote Mode
Selected Sensor
D
Hz
Dg
SI
Res
Tem
Ohm
C
6
2534.86
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Frq
Dig
Val
Number of measurements since
start of measurements on a
network. ID = 1.
Port = SDI-12
Address = 1
Measurement Count = 1032
Device Port Selection
To select the network port type for remote data acquisition operations on the VibWire-201-Pro, use the menu system to select either of the menu items shown
below.
The device will then make measurements, and transmit data over the specified network port.
Page 30 shows the menu system built into the VibWire-201-Pro.
RS485 Remote Port
Remote Mode
Selected Sensor
D
Hz
Dg
SI
Res
Tem
Ohm
C
6
2534.86
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992.28
Frq
Dig
Val
Number of measurements since
start of measurements on a
network. ID = 3.
Port = RS485
Address = 3
Measurement Count = 153
SDI-12 Port Operation
RS485PortOperation
Sets the VibWire-201-Pro to transmit data
through the SDI-12 Port
Sets the VibWire-201-Pro to transmit data
through the RS-485 Port
For single channel operation, once the output port is specified the sample data can be shown on the display.
Storing the menu option
Once the selected menu option is highlighted simple press the button
to store the new option.
Repeat the operation until the ‘ Frequency ’ display appears. See Figure 15 on
page 8.
Menu-Out
Fig-20
Fig-21
Fig-22 Fig-23
Frq
Dig
Val
Frequency
Selected Sensor
Hz
Dg
SI
Res
Tem
6
2534.86
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Hz
Ohm
C
Menu-In Me nu-In
Main Menu
Sensor No
Logger
Multiplexer
Remote
System
Remote
Address
Serial Comms
Menu-In
Select Backlight
SDI12
RS485 1200
Menu-In
Frq
Dig
Val
Frequency
Selected Sensor
Hz
Dg
SI
Res
Tem
6
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Hz
Ohm
C
Menu-In
Remote
Address
Serial Comms
Menu-In
Select Backlight
SDI12
RS485 1200
Main Menu
Sensor No
Logger
Multiplexer
Remote
System
Remote Mode
Selected Sensor
D
Hz
Dg
SI
Res
Tem
Ohm
C
6
2534.86
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992.28
Frq
Dig
Val
Port = RS485
Address = 3
Measurement Count = 153

VibWire-201-Pro User Manual 10
Device Configuration Software
The VibWire-101-Pro configuration software runs with on most modern
Windows platforms such as XP, 8.1 and 10 operating systems.
The software automatically identifies the USB port in use and allows for a true
plug and play operation. Simply enter the sensor calibration factors and select
the ‘Connect’ button to store parameters into the device.
Download the software at:
Description
Physical Size (Excluding boot cover)
Weight
Height 184 mm - Width 74 mm - Depth 32 mm
125 g
Battery
Auto-logging no back light
4 x AA - 2000 mA/Hr
6 mA - standby - 340 Hours continuous use
20 mA/Hr with display - Low
50 mA/Hr with display mode - Full brightness
150 mA/Hr with MUX-16/32 - Peak (Note-1)
Communication Ports 1 x RS-485 Slave - 1200 Baud, 8 data, 1 stop, no parity
1 x SDI-12 - - 1200 Baud, 8 data, 1 stop, no parity
1 x micro USB configuration port
External Power Supply 10 - 15V DC @ 100 mA min specification
Vibrating Wire Measurements
Analogue Input 24 Bit Sigma Delta
Differential Coil (V
+
) and Coil(V
-
) for direct connection of
sensor, excitation and resonant frequency measurement.
Digital signal processing for excellent noise rejection,
Sensor Excitation Auto-resonance - Fully automatic
Operating Frequency 400 - 15 KHz
Measurement Resolution 0.001 Hz RMS - 20 to 70 Deg C
Measurement Accuracy ± 0.014% of reading - 20 to 70 Deg C
Spectral Analysis
Resolution
Window Function
1024 line Zoom FFT - with data weighting
0.001 Hz
Hamming
Update Rate 0.25 Sec typical
SI Units Hz, Digits (Hz2/1000), Eng Units (Quadratic Cal Factors)
Temperature Measurements Used for temperature compensated vibrating wire
measurements, and stand-alone temperature sensors for
Geotechnical applications. Ratio-metric measurement.
Analogue Input 24 Bit Sigma Delta
Measurement Range - 50 to 100 Deg C
Measurement Accuracy ± 0.25 % of reading - 20 to 70 Deg C
SI Units Deg C
Cal Factors Steinhart-Hart
Beta Value - lower performance using Beta
Bridge Type Half Bridge
Expansion Options
1 x MUX-16/32 expansion unit
1..32 - 2 Wire Freq inputs
1..32 - Temp (thermistor) inputs
1..16 - 4 Wire vibrating wire sensor inputs
Scan rate 2 Sec/Chan - using expansion module
250 ms update to screen
Memory Expansion 1 x SD Card = 1 .. 32 GB
Storage file format CSV - Comma Separated Variables
Logging Rates
16 x 4 Wire Mode
32 x 2 Wire
Internal to flash card
1s, 10s, 1 Min, 10 Min, 1 Hour, 6 Hours
MUX-16/32 Expansion
30 Sec/Chan
1 minutes
No. Pre-set Sensor Configurations 10 user defined sensors options
File Type Format DOS
Operating Temp Range -20 to 75 Deg C
Storage temperature >5 Deg C with batteries installed.
Technical Specification
The current technical specification for the VibWire-201-Pro is:
Temperature Measurements
The VibWire-201-Pro is factory set to use the most common thermistor
calibration factors that is fitted into most manufactures vibrating wire sensors.
The thermistor is used to measure temperature.
The thermistor calibration factors are taken from the sensor material
manufactures data sheet and are as accurate as possible.
The voltage input measurements are factory calibrated to traceable national
standards, and can be externally calibrated upon request. There is an extra
charge for operation.
The part numbers are for 3 K Ohm thermistor commonly used by most
different VW sensor manufacturers to measure temperature
The sensors give 3 K Ohm resistance at 25 Deg C
The most common material used in these sensors uses material type F
from GE sensing.
YSI 44005
Vishay 1C 3001 B3
RS Part no: 151-215
Common VW Sensor Thermistor Part Numbers
Under most practical applications, the in-built thermistor calibration factors will
give accurate results without the User having to be concerned with
understanding of process involved.
Simply connect the thermistor output from the sensor to the VibWire-201-Pro
and the device will instantly display the temperature.
Sources of Error
The principle source of error in field measurements will the added resistance
due to long sensor wires. The resistance added to the thermistor measurement
will give a fixed offset error. Make temperature measurements as close to the
temperature sensor as is practically possible.
Calibration Factor Error
Take care when using the calibration factors supplied on a vibrating wire sensor
manufactures data sheet. The factors are often given from sample sensors taken
from a batch and not necessarily from the individual sensor being used. Where
possible ensure that the sensor manufacturer calibrates the sensor and supplies
all test data so that the calibration factors can be verified.
User Defined Stein-hart-Hart Calibration Factors
The VibWire-201-Pro has the facility to enter User defined Steinhart-Hart
calibration factors.
The calibration factors are entered into the device using the VW201cal software
package. See figure 57 on Page 20.
Sensor Information
A calibration report should be provided with each vibrating wire sensor and it will
contain all the information required to convert Hertz, the frequency value output
by the sensor into appropriate SI units (e.g., displacement, pressure etc..)
1. If the values in the Calibration Report are in digits, use the following equation
to convert the VibWire-201-Pro frequency values from Hertz to digits.
2. Use the gauge factors and polynomial provided in the Calibration Report to
calculate SI units.
The VibWire-201-Pro uses:
Calibration equation.
and this is expanded to:
when initial conditions in the measurements are involved.
The additional terms used in equation 2 only change the constant parameter
( A ) when used.
Digits = Frequency
2
1000
(Hz
2
)
1000
Natural Units = A(R1)2 + B(R1) + C + K(T1-T0) - (S1-S0) (Equ 1)
= C(R1-R0)
2
+ B(R1-R0) + A + K(T1-T0) - (S1-S0) (Equ 2)
Part No:
VibWire-201-Pro - FFT VW Sensor Interface
USB-485-Pro - Isolated USB to 485 media converter
USB-SDI12-Pro - Isolated USB to SDI12 media converter
MUX-16/32 16 x 4 Wire/ 32 x 2 Wire Expansion unit
Associated Part Numbers
Table 1
Note-1 - Use external supply for long term monitoring with MUX-16/32 unit
150 mA peak .

VibWire-201-Pro User Manual 11
Downloading and Installing device setup software
1. Download the VW201cal software from:
http://www.aquabat.net/downloads/VW201cal.zip
Run the install software script.
Follow the on-line instructions to install and activate the software.
Once activated the main Window shown in Fig 24 above will be displayed.
Automatically setting the Real-time Clock
The VibWire-201-Pro can be used as a stand-alone VW sensor data logger
recording measurements automatically, and also to take single shot readings
under ‘User’ control. In order to act as a logger the internal real-time clock has
to be set.
The real-time clock is used to keep track of the time and date of a measurement.
The clock is set automatically the VibWire-201-Pro is connected to the PC via
the USB cable and the ‘
Upload’ button is activated. Once the sensor data is
written into the device then the clock is automatically synced to the host PC.
YSI 44005
Vishay 1C 3001 B3
RS Part no: 151-215
Common VW Sensor Thermistor Part Numbers
The part numbers are for 3 K Ohm thermistor commonly used by most
different VW sensor manufacturers to measure temperature
The sensors give 3 K Ohm resistance at 25 Deg C
The most common material used in these sensors uses material type F
from GE sensing.
The VibWire-201-Pro uses the following predefined calibration parameters to
defining the operation of the 3 K Ohm thermistor temperature sensors built into
most Vibrating Wire sensors.
(Steinhart-Hart Factors)
A = 3.35E-3, B = 2.56E-4, C = 2.08E-6, D = 7.30E-8
Pre-defined Thermistor Calibration Parameters
Sensor Configuration
Figure 24 opposite shows the VibWire-201-pro Setup software used for entering the calibration
factors for a Vibrating wire sensor.
This Window is used to enter the frequency component calibration factors. The calibration factors
are used to enable the VibWire-201-Pro to display measurements directly in engineering SI units.
Pre-set Sensor Configurations
The VibWire-201-Pro cab be configured using the VW201cal.exe software which is available as a free download at:
http://www.aquabat.net/downloads/ VW201cal.zip
Features
The VW201cal software gives the User the ability to configure the VibWire-201-Pro in an easy to use Windows environment.
Automatically sets time and date to host PC.
Set the User defined frequency and temperature calibration factors.
Select preset thermistor calibration factors.
20 Pre-set sensor configuration options.
The sensor names entered into the VW201cal software appear on the VibWire-201-Pro sensor list.
The VibWire-101-Pro supports up to 20 built-in User defined vibrating wire sensor configuration options.
Thermistor Type T0, T1, T2 ….. etc
SI Unit = A + B(R1)+ C(R1)
2
+ D(T) where R1 = Current Reading
T = Temp Deg C
D = Thermal Factor
-2159.487
3.1728
Process Option
0 = Frequency,1 = Digits, 2 = SI Units
Thermistor
Calibration
Factors
Fig 24
Write configuration details
into the device.
SI Units
In order for the SI unit formulae be applied the process option has to be set to
‘ 2 ’. Fig 24 above shows how this is done.
Setting the process option to 0 or 1 shows results in Hz or Digits.
Default-Therm 3.35E-3 2.56E-4
300025 2.08E-6 7.30E-8
Select Thermistor Calibration Window
VW sensor
calibration factors
5200 2
Default Steinhart-Hart
calibration factors
Figure 25 opposite shows the thermistor calibration settings window for the VW201cal software.
The factory set default thermistor parameters for T0 are displayed.
Fig 25 Default Thermistor Calibration Factors
EPP-30V
2
-1720.23 2.8388E-1
-0.0870 T0

VibWire-201-Pro User Manual 12
Channel Expansion Options
The VibWire-201-Pro is expanded using a single MUX-16/32 expansion unit.
The expansion unit offers 16 x 4 wire or 32 x 2 wire sensor operations.
16 x 4 wire mode offers 16 x Frequency and 16 x Temperature inputs.
The 32 x 2 Wire sensor mode offers 32 x Frequency inputs or 32 x temperature measurements.
The VibWire-201-Pro can record data internally onto a SD memory card, or remotely across a digital network to a stand-alone PC running the Keynes Controls
Q-LOG applications software.
+-+-
Sensor Port
(VW-201-Pro)
Out-0 Port
(MUX-16/32)
Out-1 Port
(MUX-16/32)
Output Ports on
the MUX-16/32 Unit
32 x 2 Wire Expansion
For 32 x 2 wire operations the output ports on the MUX-16/32 expansion unit are connected together.
Full details for configuring and the MUX-16/32 unit can be seen in the User manual.
Download the User manual at
http://www.aquabat.net/downloads/mux32manualv1.pdf
16 x 4 Wire Expansion
+-+-
Sensor Port
(VW-201-Pro)
Out-0 Port
(MUX-16/32)
Out-1 Port
(MUX-16/32)
Output Ports on
the MUX-16/32 Unit
MUX-16/32
Output Ports
MUX-16/32 Expansion Unit - User manual
Fig-27
Fig-26
4 Wire operations records frequency and temperature simultaneously.
2 Wire operations records frequency or temperature but not both at the same
time.
- VW Sense + VW Sense - Therm
+ Therm
- VW Sense + VW Sense - Therm
+ Therm
Sequencing MUX
Frq
Dig
Val
Selected Sensor
Hz
Dg
SI
Res
Tem
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MUX 0
21
Sequencing MUX
Frq
Dig
Val
Selected Sensor
Hz
Dg
SI
Res
Tem
2534.86
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Ohm
C
MUX 1
12
Unit shown below is configured for 32 x 2 wire
frequency measurements.

VibWire-201-Pro User Manual 13
Number of Channels
The VibWire-201-Pro data supports 4 data recording modes:
Single Channel - Records measurements from the sensor attached directly to the instrument.
The following modes require the MUX-1632 expansion unit to be fitted:
MUX-16/32 Expansion Unit
16 x 4 Wire (VW and Temp) - 16 x Freq + 16 x Temp
32 x 2 (VW only) - 32 x Freq
32 x 2 (Freq) - 32 x Temp
when using the MUX-16/32 expansion unit 32 measurement values are stored into each record.
To select the data recording mode
1. Make sure a flash memory card is installed into the VibWire-201-Pro, See Page 5 Figure 2.
2. Starting at the default ‘Frequency’ display, use the ‘ Menu In ’ key to select ‘ System Setup ’ followed by ‘ Mux Mode ’ menu options.
The Mux Mode menu system will appear.
3. Use the ‘ Up ’ and ‘ Down ’ keys to select the mode of operation of the instrument.
Down
Up
Use the ‘Up’ and ‘Down’ keys
to select the ‘Logger’ option.
Menu system defines the number of
measurements made after each scan. The
MUX-1632 expansion unit must fitted for 16x
4 wire or 32 x 2 wire operations.
Down
Up
Down
Up
Down
Up
1 Second - only for single channel operations
10 Second
Use the ‘Up’ and ‘Down’ keys to
select the ‘Logger’ option.
Data Recording
The VibWire-201-Pro can store measurements directly on to a SD flash memory card.
Max SD Card = 32 Gb (160 million records)
DOS format file system.
The data table stores results in C.S.V. (Comma separated variable), for direct importing into spreadsheet such as Microsoft Excel.
Data Recording Options
The VibWire-201-Pro supports 3 x logging modes. Single Channel, 16 x 4 Wire and 32 x 2 Wire.
Single Channel - Continually records a single measurement from a sensor connected to the sensor port on the device.
1 x single measurement on demand.
Single Channel on MUX-16/32 Unit.
Both the 16 x 4 Wire and 32 x 2 wire recording modes require the use of the MUX-16/32 expansion unit.
16 x 4 Wire - 32 measurement values made up of
16 x Frequency + 16 x temperature.
32 x 2 Wire - 32 x Frequency measurements.
Important Note
The VibWire-2-1-Pro will adjust automatically to the fastest sample rate
allowed for the number of channels to be scanned.
The fastest sample rate that is allowed for a 32 channel operation
operation is 60 seconds (1 min).
Fig-28
Fig-29
Menu-In
Selected Scanning mode
System Setup
Log Now
Autolog Mode
Recording Interval
Set working MUX ID
Scanning mode
Menu-In
Menu-In
Frq
Dig
Val
Frequency
Selected Sensor
Hz
Dg
SI
Res
Tem
6
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Hz
Ohm
C
Single Chan
16x4 (VW and Temp)
32x2 (VW only )
32x2 (Temp only )
Main Menu
Sensor No
Logger
Multiplexer
Remote
System
Down
Up
Use the ‘Up’ and ‘Down’ keys
to select the ‘Scanning mode’
option.
Setting Scan Mode
Menu-In
Logger
Menu-In
Menu-In
Frq
Dig
Val
Frequency
Selected Sensor
Hz
Dg
SI
Res
Tem
6
2534.86
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Hz
Ohm
C
Select Recording Interval
1 Second
10 Second
1 Minute
10 Minute
1 Hour
6 Hour
Main Menu
Sensor No
Logger
Multiplexer
Remote
System
Log Now
Autolog Mode
Recording Interval
Set working MUX ID
Scanning mode
Use the ‘Up’ and ‘Down’ keys to
select the ‘Recording Interval’
option.
Set Logging Interval

VibWire-201-Pro User Manual 14
Start Measurement
Command
Description Channel
Number
No. Data Values SDI-12 Get Data Command
aM2! MUX ID=0 Chan 0..15 Chan 0 .. 15 Returns 16 values x Freq aD0! aD1! aD2! aD3!
aM3! MUX ID=0 Chan 16..31 Chan 16 .. 31 Returns 16 values x Freq aD0! aD1! aD2! aD3!
Chan 0..15 Freq
Chan 16..31 Freq
17 Commands for scanning MUX-16/32 in 32 x 2 wire mode
Table 2 below shows the commands used to scan the MUX-16/32 unit in 32 x 2 wire mode.
The MUX-16/32 unit has to be set to operate in 32 x 2 Wire mode. This is done via the VibWire-101 setup menu.
See page 17, section 25.2 for instruction in setting the ‘Scan Mode’.
In 32 x 2 wire mode the channel counter displays the range 0 .. 31.
Fig 31 - Output Ports used in 2 Wire mode.
Each get data command
returns 4 values.
to
32 x 2 Wire mode
Channel Select Display - Fig 30
When operating in 2 wire mode, the VibWire-101 scans the MUX-16/32 in blocks of 16 channels.
Under normal operating conditions Channels 0-15 are scanned first and the results stored into a data table. This is followed by
the scanning the final block of 16 channels and storing the measurements. Table 1 shows the sequence of the 2 blocks of
commands needed to scan the MUX-16/32 unit in 2 wire mode.
16 Switching between 2 & 4 Wire Mode Operation under SDI-12 Command
The MUX-16/32 expansion unit supports 2 and 4 wire VW sensor operations. The selection between 2 and 4 wire sensors is
undertaken using software commands only and these are issued across the MUX-16/32 using the SDI-12 control port. The same
procedure for issuing instructions for changing the ID number is followed as is used for selection the mode of operation.
The following SDI-12 command selects 2 or 4 wire sensor operation:
aXDn! (n=0 or 1) Sets 2 or 4 wire operations on the MUX-16/32.
Example SDI-12 command ‘ 0XD1!‘ sets MUX-342 with ID=0 to 4 Wire mode.
18 Commands for scanning MUX-16/32 in 16 x 4 wire mode
Table 2 below shows the commands used to scan the MUX-16/32 unit in 16 x 4 wire mode.
The MUX-16/32 unit has to be set to operate in 16 x 4 Wire mode. This is done via the VibWire-101 setup menu.
See page 17, section 25.2 of the User Manual for instructions in setting the ‘Scan Mode’.
In 16 x 4 wire mode the channel counter displays the range 0 .. 15.
to
16 x 4 Wire mode
Channel Select Display - Fig 31
Start Measurement
Command
MUX
Identification
Channel
Number
No. Data Values SDI-12 Get Data Command
aM2! MUX-0
Chan 0..15
Chan 0 ..15 returns 32 values
16 x Freq + 16 x Temp
aD0! aD1! aD2! aD3! aD4! aD5! aD6! aD7!
To VW frequency
port on the VW101
Fig 32 - Sensor Output Ports
To temperature
port on the VW101
After each MUX has been scanned, and all 32 sensor readings have been taken, then the following command is required
to download the data from the VibWire-101 to a data table in the AquaLOG data logger. The same command should work on
any suitable SDI-12 data logger.
Get data: aD0! aD1! aD2! aD3! aD4! aD5! aD6! aD7!
16 x Temperature Readings
where each command aD0! returns 4 values
16 x Freq Readings
Table 2
Table 3

VibWire-201-Pro User Manual 15
16 x 4 Wire Expansion
MUX-16/32
Output Ports
+-+-
Sensor Port
(VW-201-Pro)
Out-0 Port
(MUX-16/32)
Output Ports on
the MUX-16/32 Unit
Out-1 Port
(MUX-16/32)
Frequently Asked Questions
1. What cable is used to connect the VibWire-201-Pro to a data logger.
A single 4 core ribbon cable is all that is required for the most common SDI-12 and RS-485. No
special cabling is required for this instrument.
Figure 61 on page 21 shows the connections to a logger
Farnell Web Site: http::/www.farnell.co.uk
Farnell Part No. 150427
Manufactures Part No. 05091504-01-50M .
2. What might cause an VibWire-201-Pro to not communicate with a data logger?
There is no programming required for setting up and using the VibWire-201-Pro.
The most common cause for lack of communication is faulty wiring. Check that the cable cores
are correctly terminated by into the plugs. Use a DVM to test each core and pin on the plugs
for continuity.
Make sure the correct network port is selected.
For SDI-12 communications see menu system in Figure 21 on Page 9,.
For RS-485 option - see menu system on Figure 22 on page 9.
Network ID number
Make sure the ID number used to identify the VibWire-201-Pro on a network is set correctly.
See menu system on page 29 section ‘ Setting network address’ , or by the standard SDI-12
commands on page 20. A full list of User commands is shown on page 19.
The ID number for the measurement command used to acquire data from the VibWire-201-Pro
must mach the ID number set in the device.
Logger using command: 3 M! 3 D0! - then the ID number should be set to ‘3’.
Page 30 shows the menu options to set the ID number.
IMPORTANT NOTE
When multiple devices are being used on the same network, each device must have a unique
ID number assigned. Failure to do so will prevent the VibWire-201-Pro from communicating to
a logger unit.
How fast can the VibWire-201-Pro make a measurement?
Currently the fastest data recording rate is 1 measurement / Second for a single channel.
The fastest sample rate is supported on the SDI-12 and 485 network measurements using the
Q-LOG free data acquisition and display software, and to the in-built data recording to the flash
memory card.
Where Can I download a copy of Q-LOG software ?.
Download a copy of the Q-LOG software at:
http://www.aquabat.net/QLOGFree/qlogv2.html
Erratic Measurements - most common cause.
When the battery level goes below 3.9 Volts the measurements can be come noisy and erratic.
Replace the batteries in the unit for a new set, or connect an external power supply. Faulty
sensor coil seating which can be seen in the sensor results spectra.
How do make measurements on my PC without any programming experience.
Use the free Keynes Controls Q-LOG software which can downloaded without restriction from
the companies web site, and one of the USB-SDI12-Pro or USB-485-Pro media converters. The
Q-LOG Windows software can be configured
The Q-LOG software gives complete control of the data acquisition operations for the VibWire-
201-Pro in a simple to use Windows environment. See page 18 for additional information.
The USB-SDI12-Pro and USB-485-Pro media converters can both be power the VibWire-201-Pro
direct from a PC USB port. No additional power supply is required.
Install the software - Assign USB COM Port details - Scan Network ( Identify Instruments) - Start Data Acquisition.
The Log files are stored to C:/Q-LOG/Logfiles/’Timestamp-file’.TXT in a format suitable for reading
by a spread sheet package,
‘Timestamp-file.TXT ’ is a unique log file in CSV ( Comma Separated variable).
Remote Mode
Selected Sensor
D
Hz
Dg
SI
Res
Tem
Ohm
C
6
2534.86
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Frq
Dig
Val
Port = SDI12
Address = 3
Measurement count = 4312
IMPORTANTNOTE
TheMUX-16/32expansionunitisusedtoexpandthe
VibWire-201-Proforadditionalchannel.
Fulldetailsforsensorconnectionandoperationcanbe
foundintheUsermanualat:
http://www.aquabat.net/downloads/mux32manualv1.pdf
TheMUX-16/32unitoperatingmode,16x4wireor32x2wire
isassignedusingtheQ-LOGsoftwareviathein-built
SDI-12ControlPort.
32 x 2 Wire Expansion - Frequency Measurements
+-+-
Sensor Port
(VW-201-Pro)
Out-0 Port
(MUX-16/32)
Output Ports on
the MUX-16/32 Unit
Out-1 Port
(MUX-16/32)
MUX-16/32
Output Ports
32 x 2 Wire Expansion - Temperature Measurements
+-+-
Sensor Port
(VW-201-Pro)
Out-0 Port
(MUX-16/32)
Output Ports on
the MUX-16/32 Unit
Out-1 Port
(MUX-16/32)
MUX-16/32
Output Ports
Fig 33
Fig 34
Fig 35
The maximum cable core diameter is 2 mm for
the sensor terminated with a plug for
connection to standard sensor input.
The sensor terminal posts can take larger
diameter cables.
Sequencing MUX
Frq
Dig
Val
Selec ted Sensor
Hz
Dg
SI
Res
Tem
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MUX 1
12
Sequencing MUX
Frq
Dig
Val
Selected Sensor
Hz
Dg
SI
Res
Tem
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MUX 1
20
Sequencing MUX
Frq
Dig
Val
Selected Sensor
Hz
Dg
SI
Res
Tem
99.00
9.90
3003.56
24.89
9.90
Ohm
C
MUX 1
20
Earth
-VW Sensor +VW Sensor
Earth
- Therm + Therm
Earth
-VW Sensor +VW Sensor
- Therm
+ Therm

VibWire-201-Pro User Manual 16
Selecting a MUX-16/32 Channel
The VibWire-201-Pro can be used to manually select a channel on the
MUX-16/32 expansion unit and take readings.
The feature enables the user to test sensors during an installation, or to use the
MUX-16/32 expansion unit as a switch box. The channel selection works in 16
x 4 wire and 32 x 2 wire modes.
MUX-16/32 Settings for operation with VibWire-201-Pro
The MUX-16/32 must be set to ID = 0
The setting of the MUX-16/32 ID number is easiest set using a USB-SDI12-Pro
media converter and Q-LOG software. See Page H Appendix A for details.
D
N/A
Out-1 Port
(VibWire-201-Pro)
Control Port
(MUX-16/32)
Mux-16/32
Channel Control
Port
12V
0V
D
N/A 12V
0V
Wiring diagram for the MUX-16/32
control port to the VibWire-201-Pro
Fig 36
Sensor Output
Ports
1. Connect the MUX-Ctrl port on the VibWire-201-Pro to the Control port on the
MUX-16/32 expansion unit.
Figures 33 to 35, page 15 above show the wiring diagram for the MUX control
ports.
MUX-16/32 User Manual
Full details for the operation and configuration of the expansion unit can be
found at:
http://www.aquabat.net/downloads/mux32manualv1.pdf
MUX Control Port
Main Menu Actions Menu
Down
Up
to
16 x 4 Wire mode
Channel Select Display
Off - Initial setting
Sequencing MUX
Frq
Dig
Val
Selected Sensor
Hz
Dg
SI
Res
Tem
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Ohm
C
MUX OFF
MUX-ID No
0
MUX Chan No.
32 x 2 Wire mode
Off - Initial Position 0 - 15 (4 Wire) and 0 - 31 (2 Wire)
The menu system above shows the commands to follow to manually adjust
the active MUX channel.
Changing the MUX Channel Number
Use the ‘ Up ’ and ‘ Down ’ keys to manually select the MUX-16/32 channel.
As the keys are pressed the MUX-16/32 channel will increment.
The Channel counter on the menu system will increment/decrement at the
same time as the MUX-16/32 unit.
Channel
Counter
to
Signal and Control Ports
Fig-37
Fig-38
Fig-39
Fig-40
Manually setting the MUX-16/32 Channel
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Menu-In Menu-In
Multiplexer
Manually set MUX
Set working MUX ID
Menu-In
Sequencing MUX
Frq
Dig
Val
Selected Sensor
Hz
Dg
SI
Res
Tem
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Ohm
C
MUX 0
Frq
Dig
Val
Frequency
Selected Sensor
Hz
Dg
SI
Res
Tem
6
2534.86
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Main Menu
Sensor No
Logger
Multiplexer
Remote
System
MUX-ID No
24
MUX Chan No.
Manually set the MUX-16/32 channel number. The channel range will depend on the scan mode assigned.
The MUX Chan number indicator will change as the ‘Up’ and ‘Down’ keys are pressed.
MUX 0 .. 15 4 Wire Mode - MUX-16/32 Channel counter changes between 0 ..15
0 .. 31 2 Wire Mode - MUX-16/32 Channel counter changes between 0 ..31
Use the ‘ Up ’ and ‘ Down ’ buttons to change the MUX channel.
The channel counter on the MUX-16/32 will update automatically.
The image above shows the Initial Startup display
should the MUX channel selection be activated without
a MUX-16/32 expansion unit connected.
FFT Sensor Spectra
Selec ted Sensor
Hz
Dg
SI
Res
Tem
Ohm
C
6 V
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Frq
Dig
Val
0 1 2 3 4 5 6 10 11 12 13
14 15
7KHz

VibWire-201-Pro User Manual 17
Sensor Configuration Example - Piezometer
The following example shows how to configure the VibWire-201-Pro to use an Encardio-rite vibrating wire piezometer water level sensor. The piezometer is
configured in a similar way as to a strain gauge but has the added complication for requiring barometric correction for true water level measurements.
The example will use the linear formula to convert frequency to pressure into SI units of k Pa. (Kilo Pascal )
A copy of a sample calibration data sheet used in this example is shown in Appendix-A .
The example demonstrates how to allow for initial conditions to improve the accuracy of the measurements.
Temperature Compensated Calibration Factors - Results in Natural (SI) Units
The example below demonstrates how to use the calibration factors on a sensor data sheet, and local initial conditions to determine the factors to be used by the
VibWire-201-Pro to give results in SI Units. The example sensor data sheet, see Appendix-B page 32 gives results in kPa. Use suitable scaling factors to convert
the output into other SI Units. The formula section of Q-LOG can be used to convert pressure into other SI Units.
= C(R1-R0)
2
+ B(R1-R0) + A + K(T1-T0) - (S1-S0)
where R0 = Initial reading in Digits
T0 = Initial sensor temperature Deg C
R1 = Current Frequency reading in Digits
T1 = Current temperature reading in Deg C
S1 = Current barometer value - SI Unit KPa
S0 = Initial Barometer reading - SI Unit KPa
Examining the formula now gives the parameters required for the VW201Cal software
P(kPa) = G(R1-R0) + K(T1-T0) - (S1-S0) — Sensor formula for conversion frequency (in Digits) to kPa
— Formula used by VW201pro software for configuration
For this example there is no C(R1-R0)
2
and there is no barometer to correct for local barometric conditions.
Therefore the absolute water level measurements in kPa formula is now:
P(kPa) = B(R1-R0) + K(T1-T0) - temperature corrected absolute level readings
where A B and C are the calibration factors used in the VW201pro software.
where G = Linear gauge factor from the calibration data sheet.
The initial condition measurements from the sensor are: 6064.0 Digits at 14 Deg C.
Different initial conditions will change final offset value only.
Use the Barom-SDI12 or Barom-485 digital
barometer modules to give local barometric
levels in kPa for local atmospheric effects.
Important Information
P(kPa) = G(R1-6064) + K(T1-14)
= 2.8388E-1*(R1-6064) - 0.087*(T1-14)
= (2.8388E-1*R1)-1721.448 - (0.087*T1)-1.218
= (2.8388E-1.R1) - (0.087.T1) -1720.23
This formula gives the output from the sensor in k Pa and allows for local temperature correction.
G = 2.8388E-1 - See Cal Data sheet
A = -1720.23 B = 2.8388E-1 D = -0.0870
EPP-30V
2
-1720.23 2.8388E-1 -0.0870
Figure 41 shows how the VW201cal software is configured for a
Encardio-rite EPP-30V piezometer as sensor 3.
The output SI unit value will be in units kPa.
The output will be temperature compensated.
Process Option setting
In order for the VW201-Pro to use the calibration factors in the
software then the process option has to be set to 2 .
Thermistor Type
Enter thermistor type into cell labelled ‘ THERM ’.
Results in Deg C.
Pre-set Sensor Configuration Settings
Once the calibration factors have been determined and set into
the VW201cal software, then they will be automatically loaded
into the VibWire-201-Pro. This is done by simply connecting the
device to the host PC and pressing the ‘ Connect’ Button.
All defines sensor types will be loaded into the device and can
be selected using the menu system. See Figure 44 opposite.
Fig 41 - VW201Cal Software - EPP-30V Piezometer.
Process option - Digits
Simplified Calibration Factors
As is shown above the temperature effects on the sensor are not significant and for most applications can be ignored.
If the initial conditions are: 6064.0 Digits
then the simplified formula becomes much easier to use
kPa = G (R1-6064) gain from the calibration data sheet G = 2.8388E-1 therefore kPa = 2.8388E-1(R1 - 6064) where R1=current reading
= 2.8388E-1 - 1721.44
The output on the VibWire-201-Pro will now be the height of the water above the initial condition starting point in SI units kPa.
This gives the calibration factors for the VW201cal software as A = -1721.44 and B = 2.8388E-1.
Model: Barom-SDI12
Frq
Dig
Val
Fig 43
Fig-42
T0
VWP-2021 2
3.22346
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Menu-In
Frq
Dig
Val
Frequency
Selected Sensor
Hz
Dg
SI
Res
Tem
6
2534.86
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Menu-In
Select Sensor No
Sensor no: 0
Name: Undefined
Main Menu
Sensor No
Logger
Multiplexer
Remote
System
Select Sensor No
Sensor no: 3
Name: EPP-30V
Use the ‘ Up’ and ‘ Down ’ keys to select the sensor type.
The assigned sensor calibration factors will then be used by the VibWire-201-Pro to
determine the SI units for any sensor that is attached.
Default display with
no sensors defined.

VibWire-201-Pro User Manual 18
0I!013KEYNESVWRDOA001 Vibrating Wire Readout Unit D
Q-Log - Quick User Guide
The VibWire-201-Pro is integrated into the Q-LOG data acquisition software.
The VibWire-201-Pro can be used with both the SDI-12 and RS-485 ports in
the Q-LOG software.
A copy of the Q-LOG software can be downloaded at:
http://www.aquabat.net/QLOGFree/qlogv2.html
A copy of the User manual can be downloaded at:
http://www.aquabat.net/downloads/Q-log-guidev2.pdf
Factory Default Settings
The VibWire-201-Pro has the following default settings
ID = 0 Single Channel Operation for both SDI-12 and RS-485 networks
Sample Rate Options
The sample rate options for single channel operation is:
1s , 10s, 30s,1 min, 10 min, 1 hour, 6 Hours.
Maximum sample rate = 1 Hz.
Q-LOG Devices List Window.
Example
The example below assumes that the Q-LOG software has been installed and
that a USB-12-Pro media converter is in use. 3rd party SDI-12 media converters
will work with the Q-Log software but Keynes Controls do not support them.
USB-SDI12-Pro media converter using COMM Port 1 on the operating system.
The Q-LOG software can be used by third party media converters but they are
not supported by Keynes Controls Ltd.
SDI12
Gnd/0V
12 DC
VibWire-201-Pro
SDI-12 Port
(VibWire-201-Pro)
Network Port on
(USB-SDI12-Pro)
SDI-12 Data
SDI-12 Data
+12V DC
+12V DC
0V/Gnd
0V/Gnd
Image below shows how the
VibWire-201-pro is connected
to the USB-SDI12-Pro media
converter.
SDI-12 Port
(VibWire-201-Pro)
Network Port on
(USB-SDI12-Pro)
SDI-12 Data
SDI-12 Data
+12V DC
+12V DC
0V/Gnd
0V/Gnd
External +12V DC
0V/Gnd
Ports on the
USB-SDI12-Pro
device
Figure 44 opposite shows how to connect a
VibWire-201-Pro to the SDI-12 network using the
USB-SDI12-Pro media converter.
Important Note
Ensure that the COMM port number for the USB
media converter and network type have been set
in the ‘Configuration’ Window of Q-LOG.
Failure to do so will prevent the software from
identifying the VibWire-201 device.
Logging Configuration Window
Enter Comm Port identified for USB media converter
Example shows COMM Port-1 . Use device manager to locate port no.
Data Recording Sample Rate - 60 Secs
Log Filename - 20160215_1116.txt (time stamped file)
Automatically create a new time stamped log file.
- Unique file each time selected.
Network Type Selection - SDI-12
Options for SDI-12 and RS485 networks
To PC USB Port
Scanning for Devices
Select the ‘ Scan for devices ’.
The Status LED indicators on the USB-SDI12-Pro
media converter illuminate during the scanning
operations.
Before data can be obtained from a device on the SDI-2 network it first has to
be identified.
The procedure for identifying sensors and interfaces on a network is called
‘ Scanning for Devices ’. Figure 48 below shows how to Scan for devices.
External Power Supply
For stand-alone operations, or when multiple VibWire-201-Pro are connected
onto the network, then an external power supply should be connected to
external power supply port on the USB-SDI12-Pro.
The USB-SDI12-Pro can power 2 units directly from the USB port of a PC,
For a single device connected connected to a SDI-12 network then the device
list will appear as shown below.
Any addition sensors on the SDI-12 network require a separate and unique ID
number, and will appear in the list below.
Product: ID string:
VibWire-101 VW sensor interface 13KEYNESCOVW101A011
VibWire-108 VW sensor interface 13KEYNESCOVW108A016
PIEZO-RM water level sensor 13KEYNESCOPRESR001
Barom-SDI-12 barometer 13KEYNESCOBAROMR003
I-P-I 13KEYNESCOIPINCL005
AquaDAT sensor interface 13KEYNESCOAQUDAT008
Single channel strain gage 13KEYNESCOSTRAIN027
VibWire-201-Pro 13KEYNESVWRDOA001
Common Keynes Controls device identifier strings.
Start Data Acquisition
SDI-12
RS-485
D+ D- 12V G
12V GS
Network
Ports
Press the ‘Setup’ button - from the list
select ‘ Vibrating Wire Readout ’.
High speed single channel data acquisition readings
for a single channel vibrating wire sensor can be made.
PC Data Acquisition - Start data recording
Select the ‘ Start Logging ’ menu option and measurements will be made and
data stored to the results file. See Fig QQ below.
If a USB-SDI12-Pro or USB-485-Pro media converter is being used then the
device status LED indicators will flash after each measurement.
Q-LOG will run with 3rd party media converters but Keynes Controls do not
support devices we don’t manufacture.
Start Data Logging
menu option
Note.
When multiple devices and interfaces are on
the same network then select ‘ Auto Assign ’
to set cell locations into the data table. The
Auto assign option will make sure the results
from different devices wont overlap.
Fig-50
Fig-44
Fig-45
Fig-46
Fig-47
Fig-48
Fig-49
Remote Mode
Selected Sensor
D
Hz
Dg
SI
Res
Tem
Ohm
C
6
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Frq
Dig
Val
Port = SDI-12
Address = 1
Measurement Count = 1032

VibWire-201-Pro User Manual 19
SDI-12 / RS-485 Supported Commands
Description Master
VibWire-201 Response
Acknowledge active
a! a\r\n
Send ID:
provided to complement SDI-12 protocol
aI! a13KEYNESVWRDOA001\r\n
Part Description assigned by Keynes
Address Query
identifies instrument address
and commonly used on single instrument
operations only.
?!
Used to make command set SDI-12 compatible
a\r\n
Where a = ID number
0 - 9 (standard) / (a..z) Enhanced SDI-12
0 - 9 / a - z for RS485
Change Address:
used to change instrument address from a(inital) to b
new ID for network operations
aAb!
a = initial address b = new address
b\r\n
a : b = number 0 - 9 or a - z
Start Measurement
instruct an instrument to make measurement
aM!
a = address of instrument
example 0M! starts scan for ID 0
a0261\r\n ****
instrument with address a returns 1 x 4 wire reading in 1
second.
Concurrent measurement:
Used for starting a measurement for all instruments on a
network at the same time.
This command frees RS-485 bus for other devices
aC!
start measurement instrument address ‘ a’
a0268\r\n
initial response only after receipt of instruct and no response
when data ready to be sent.
MUX-16/342 Expansion Unit
32 x 2 Wire Measurements
aM2! aD0! aD1! aD2! aD3! - 16 x Freq
aM3! aD0! aD1! aD2! aD3! - 16 x Freq
16 x 4 Wire Measurements
aM2! aD0! aD1! aD2! aD3! aD4! aD5! aD6! aD7!
D0-D4 = Frequency D4-D7 = Temperature
+xxxx.x+xxxx.x+xxxx.x+xxxx.x\r\n
Thermistor 1 & 2
VibWire-201 supports 3 thermistor types
Thermistor Type 1
Temperature sensor settings
Parameters from the sensor calibration sheet
aXT1RE!
aXT1T0! = 25
aXT1BET!
Resistance at 25 Deg C
T0 - generally 25 Deg C
Beta Value
Steinhart-Hart Parameters
Thermistor resistance/temp calculation
aXT1ST0!
aXT1ST1!
aXT1ST2!
aXT1ST3!
A in Steinhart-Hart
B in Steinhart-Hart
C in Steinhart-Hart
D in Steinhart-Hart
Thermistor Type 2
Temperature sensor settings
Parameters from the sensor calibration sheet
aXT2RE!
aXT2T0! = 25
aXT2BET!
Resistance at 25 Deg C
T0 - generally 25 Deg C
Beta Value
Steinhart-Hart Parameters
Thermistor resistance/temp calculation
Page 36 shows sample calibration data sheet
aXT2ST0!
aXT2ST1!
aXT2ST2!
aXT2ST3!
A in Steinhart-Hart
B in Steinhart-Hart
C in Steinhart-Hart
D in Steinhart-Hart
VW Sensor Input Channel Settings
Sets the process option for frequency calculations
aXCH0FN!
F = Frequency type
N = VW Channel 0 .. 7
0 = output in Hz
1 = output in digits = F^2/1000
2 = use formula
A + B*digits + C*digits^2 + D*temperature
digits = Frequency
2
in units of Hz
2
Thermistor Temperature Calculation
aXT1TYn!
a = ID n = integer 0 .. 2
0 = resistance ratio - thermistor data sheet (R
t
/R
25
)
1 = Beta value calculation
1/T = 1/T
0
+ log(r)/Beta where r = R
t
/R
25
2 = Steinhart-Hart equation
1/T = A + B(Ln R
t
/R
25
) + C(Ln R
t
/R
25
)
2
+ D(Ln R
t
/R
25
)
3
The following commands are supported by the VibWire-201-Pro and are used by data loggers and data acquisition systems. The commands have been
included to allow the VibWire-201-Pro to operate easily with third party data loggers that support industry standard SDI-12 command set.
Prefix the commands in Table 3 below with the ‘%’ for use in RS-485 data logger and acquisition systems.
Example, the command ‘ al! ’ becomes ‘ %al! ’. – access the device identifier string.
Table 3

VibWire-201-Pro User Manual 20
Examples Of Using RS-485/SDI-12 Commands
The following examples show how to undertake the various tasks needed to setup and make readings across the RS-485 and SDI-12 networks. The command
structure between the SDI-12 and RS485 models is essentially the same except all RS-485 commands use the ‘ % ’ sigh at the start of all instructions.
The SDI-12 networks only supports up to 10 instruments with address range: 0 to 9 unless otherwise stated.
Changing the ID Number (address)
The following example demonstrates how to change the instrument ID number from the default factory setting 0 to 5.
Use the command ‘ a A b! ’ where a = Start ID b = Final ID
SDI-12 master sends: ‘ 0A5! ’ Instrument responds 5\r\n Return New Line (5 representing new ID number)
RS-485 master sends ‘ %0A5! Instrument responds 5\r\n Return New Line (5 representing new ID number)
ID Number Query
This command has been included to remain compatible with the SDI-12 and should be used for used with single instrument operations only. Useful command
when identifying ID numbers for instruments to be deployed on a multi-instrument network.
The example below is to show the ID number of a single instrument
Use the command ‘ ?! ’ .
master sends: ‘ ?! ’ Instrument responds 3 \r\n Return New Line (3 is the ID number)
Start a measurement for Instrument on a network
The following example shows how to start measurements on instruments with ID numbers 2
The instruments will start their measurement operations but will not send data across the network until instructed to do so.
Use the command ‘ aM! ’ where a = Instrument ID Number
Use the command ‘ %aM !’ for RS-485 network operation
Problems with measurement systems - Spikes in measurements
A common source of noise for vibrating wire measurement systems is earth - current loops.
Earth loop effects cause spikes in measurement values and can be intermittent. Earth loops are often caused by power supplies and multiple earth connections
between different sections of a measurement system. Earth loop noise can cause random spikes
Figure 51 shows how some distributed applications are wired together
and this is how different earth potentials can form current loops between
the subsystems.
Isolated Power Source
The VibWire-201-Pro operates using its internal AA batteries
and as such is totally isolated from the power sources used in
permanently installed data acquisition and recording systems.
The VibWire-201-Pro when running on batteries operates in full isolation
to any other device.
metal mounting panel
Data
Acquisition
System
Local Earth
Local
Instrumentation
metal mounting panel
Local Earth
Local
Instrumentation
metal mounting panel
Local Earth
Local
Instrumentation
Data
Acquisition
System
Data
Acquisition
System
Network
Link
Network
Link
Connection to
MUX-16/32 expansion
unit.
Diagnostics
The VibWire-201-Pro is a perfect tool to assist engineers in the setup and
diagnostics of Geotechnical systems.
A common problem is that a geo-technical monitoring system seems to be
running correctly and then spikes appearing at random in a sensor trace keep
appearing.
Spikes can be caused by interference on a sensor cable or loop noise.
Fit the problematic sensor signal directly into the VibWire-201-Pro and set it up
for stand-alone logging to the flash memory card. The logging operation can be
set fast for short periods of time, or to save battery life to slow sampling.
The device runs completely isolated from any other device. The recording will
be be purely the sensor signal and will not be effected by any other local device.
If the sensor trace shows no sign of irregularities then the problem is on the fixed
installation.
It is highly unlikely that cable pickup noise, including any environmental noise
such as mains 240V 50 Hz can effect any measurements on the VibWire-201.
A sensor can be isolated from a main system and run independently.
MUX-16/32 Expansion Unit
A MUX-16/32 expansion unit can be run directly from the batteries in the
VibWore-201-Pro so blocks of sensors can be tested directly and the results
recorded by the device to the flash memory card.
Fig-51
Fig-52 MUX Control Signal Connection to VibWire-201
D
N/A
Out-1 Port
(VibWire-201-Pro)
Control Port
(MUX-16/32)
12V 0V
D
N/A 12V
0V