1. Configure the VWIRE 305 for measurements, see
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.
(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 (
(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
