Table 14-1: StrainCalc() configuration codes
BrConfig Code
Configuration
5
Full-bridge strain gage. Half the bridge has two gages parallel to +ɛ
and -ɛ, and the other half to +
ν
ɛ and -
ν
ɛ
6
Full-bridge strain gage. Half the bridge has two gages parallel to +ɛ
and -
ν
ɛ , and the other half to -
ν
ɛ and +ɛ:
Where:
ν
: Poisson's Ratio (0 if not applicable).
GF: Gage Factor.
V
r
: 0.001 (Source-Zero) if
BRConfig
code is positive (+).
V
r
: –0.001 (Source-Zero) if
BRConfig
code is negative (–).
and where:
"source": the result of the full-bridge measurement (X = 1000 • V1 / Vx) when multiplier = 1 and offset = 0.
"zero": gage offset to establish an arbitrary zero.
14.3.3 Accuracy for resistance measurements
Consult the following technical papers for in-depth treatments of several topics addressing
voltage measurement quality:
l
Preventing and Attacking Measurement Noise Problems
l
Benefits of Input Reversal and Excitation Reversal for Voltage Measurements
l
Voltage Measurement Accuracy, Self- Calibration, and Ratiometric Measurements
NOTE:
Error discussed in this section and error-related specifications of the CR300 series do not
include error introduced by the sensor, or by the transmission of the sensor signal to the data
logger.
For accuracy specifications of ratiometric resistance measurements, see
(p. 189). Voltage measurement is variable V
1
or V
2
in resistance measurements.
Offset is the same as that for simple analog voltage measurements.
14. Measurements
77