Dataloggers, Readout Units and Software

Compact-RIO Module for VW Sensors

///Compact-RIO Module for VW Sensors


CRIO VW is our hardware module for the reading of vibrating wire instruments and NTC, developed to be integrated into the CompactRIO platform of National Instruments Co.
Pizzi Instruments, with more than 30 years of experience in the development, manufacture and installation of sensors for geotechnical and structural monitoring systems, has been selected and accredited by National Instruments as “alliance partners” for the development of these modules for integration into its products.
The cRio_VW01 module has been developed by Pizzi Instruments, in close collaboration with National Instruments technicians, to allow the platform to integrate with vibrating wire instruments which are widely used for precision, reliability and stability in all geotechnical, structural and hydrological monitoring. The cRio_VW module, can read most vibrating wire sensors present on the national and international market, ensuring perfect integration into National Instruments systems hardware
The cRio platform is a modular system which, due to its flexibility, can be connected to the desired interface modules and allows the realisation of any solution for the acquisition of activity data or for monitoring activity . Combination with cRIO_VW01 allows the the creation of extremely versatile and attractive solutions for geotechnical, structural and hydrological monitoring systems.
The integration of the CompactRIO + cRIOVW01 systems, with MUX8_2 multiplexer modules and module Driver cRio_D_Mux01, developed by Pizzi-Instruments, allows the configuration of multi-channel centralization systems for up to 128 sensors.


Vibrating wire sensors, thanks to their reliability, accuracy and stability, are widely used in structural, geotechnical and hydrological monitoring.
Typical applications for systems with CompactRIO Vibrating Wire can be found in the monitoring of:

  • Dams
  • Bridges
  • Tunnels
  • Landslides
  • Structures adjacent to construction zones or with structural problems
  • Mines
  • Piles
  • Other

Features and Benefits

The main characteristics of CompactRIO and cRIO VW01 modules and accessories are::
Versatility of application
Integration and compatibility with NI modules (allows configuration of modular systems to customer’s specifications and requirements).
Accuracy and reliability of measurements and monitoring
Highly robust components for harsh environments
Easy configuration thanks to LabVIEW
In addition the simple module cRio_VW01 offers:
– Reading interface for vibrating wire sensors, developed for National Instruments CompactRIO systems
– High resolution measurement of VW and NTC
– Reconfigurable multi-channel systems with centralization of up to 128 channels per system
– Versatility of use with CompactRIO , possible to integrate additional modules to create customized systems.
-.Analog filters to eliminate measurement problems related to electrical noise
– Simple configuration via an interface developed in LabVIEW environment
– Easy to create applications for monitoring, measurement and analysis via programming in Labview graphical environment
– Self-diagnostic for monitoring data reliability, correct functioning of the module and system, and sensor signal quality.
– Possible to interface with most vibrating wire sensors in commerce.
– Robust system developed to function in critical environments.
– Accurate overvoltage protection concept

Measurement Principles

The cRio_VW01 module has been developed in accordance with the specifications and technical standards of National Instruments
To guarantee perfect operation and compatibility with National Instruments hardware, the module has passed all tests performed by National Instruments Corporate, in its offices in Austin, Texas, USA.
NI CompactRIO is the embedded monitoring system and control offered by National Instruments, a leader in automation and control systems.
NI CompactRIO is composed of the “embedded” NI controller for communication and processing, the chassis, in which the FPGA (field programmable gate array) chip, programmable by the users, is housed and a number of extractable modules developed and produced by Pizzi Instruments.
For programming and configuring the system makes use of LabVIEW graphical programming tools.
The cRio_VW01 module has been developed to ensure the reading of most of the vibrating wire sensors present on the national and international market, with a resolution of 0.02 Hz for vibrating wire instruments and 24 bits for NTC.
The use of digital filters and self-diagnostic functions eliminates problems with incorrect measurements due to electrical noiseSystem configuration is as simple and intuitive through the configuration software platform built with LabVIEW graphical development.
The potential of the LabVIEW programming environment allows easy customization of both the configuration and system management interfaces, and the creation of professional software platforms for control, analysis and measurement of the system and of the monitoring data


Format CompactRIO 9022 (chassis c-Rio 9111)
Target Windows / Real Time
Type of measurement Vibrating Wire/ NTC  temperature
Type of insulation Ground insulation – ground
Type of vibrating wire sensors Piezometers, crackmeters, clinometers, strain gauges, load cells, pressure cells, settlement cells, etc.
Type of thermistor NTC 3K
Conformity ROHS Yes

Analog Input

Channel 2
Resolution VW: 0,02 Hz/Temp. 24 bit
Accuracy VW: 0,02 Hz/Temp. 0,1°C
Sampling frequency 1 S/s
Measuring range VW: 300÷6.000 Hz / Temp: – 40,0+80,0 °C
Simultaneous sampling No


Mode SPI
Baud rates 1 Mbit/s

External power supply

Power supply voltage 9÷36 Vdc
Power operation mode 3VA
Power sleep mode 1VA
Voltage insulation between electronic module and power supply 150 KV
Insulation capacity between the electronic module and the power supply 200 pF max
Insulation resistance  between the electronic module and the power supply > 1 GigaOhm

Interface BUS CompactRIO

Clock frequency interface SPI 1 Mhz
Isolation voltage between electronic module and CompactRIO bus 2500 Vrms
Maximum current absorption OperationMode 8 mA max
Maximum current absorption
0,1 mA max

Physical characteristics

Dimension (mm) 88x70x23
Weight (g) 140
Operating temperature  (IEC 60068-2-1) – 40÷+70°C
Storage temperature
(IEC 60068-2-1)
– 40÷+85°C
Protection level (IEC 60529) IP 40
Operating humidity (IEC 60068-2-56 10÷90% RH non condensing
Storage humidity 5÷95% RH non condensing
Pollution degree (IEC 60064) 2
Maximum altitude 6.000m a.s.l.

Type of measurement CRio_VW

Type of measurement Range of Measurement U. of M. Type of sensor
CV OG 0,1200÷1,6000 Khz2 Galileo Vibrating Wire (350÷1250 Hz)
CV OG1 0,1200÷1,6000 Khz2 Pizzi Instruments  Vibrating Wire (350÷1250 Hz)
CV mode A 166,2÷2222,2 μsec Vibrating Wire  (450÷6.000 Hz)
CV mode B 1440,0÷12250,0 Hz2x 10-3 Vibrating Wire (1200÷3500 Hz)
CV mode F 6250,0÷36000,0 Hz2x 10-3 Vibrating Wire (2500÷6000Hz)
NTC -40,0 ÷+80,0 °C Thermistor NTC 3 K
TEST Functional test

Depending on system configuration, CompactRIO can be combined with the following components

MUX8_2 Multiplexer Group for 8 channels for selection of connected instruments
For vibrating wire sensors two channels for instrument are necessary.
2 channels necessary for vibrating wire sensors.
cRIO_D_Mux01 Driver to manage the multiplexer to a maximum of 16 Mux modules per driver.

Technical Assistance

If you have any requests or questions about our instruments or if you have special needs that require different solutions from the standard, please contact us. Our team will provide all the necessary information and will be very happy to work with you to study, develop and customize instruments and solutions suitable for your specific needs.

All information in our datasheet is subject to change without prior notice.
Please check the datasheet/details carefully and contact Pizzi Instruments for further information.