Campbell CR310 User Manual

22.11 Improving voltage measurement quality
The following topics discuss methods of generally improving voltage measurements:
22.11.1 Deciding between single-ended or differential measurements 189
22.11.2 Minimizing ground potential differences 190
22.11.3 Minimizing power-related artifacts 191
22.11.4 Filtering to reduce measurement noise 193
22.11.5 Minimizing settling errors 196
22.11.6 Factors affecting accuracy 198
22.11.7 Minimizing offset voltages 199
Read More: Consult the following technical papers at www.campbellsci.com/app-notes 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 Accuracy, Self-Calibration, and Ratiometric Measurements
22.11.1 Deciding between single-ended or differential
measurements
Deciding whether a differential or single-ended measurement is appropriate is usually, by far, the
most important consideration when addressing voltage measurement quality. The decision
requires trade-offs of accuracy and precision, noise cancellation, measurement speed, available
measurement hardware, and fiscal constraints.
In broad terms, analog voltage is best measured differentially because these measurements
include the following noise reduction features that are not included in single-ended
measurements.
l
Passive Noise Rejection

o
No voltage reference offset

o
Common-mode noise rejection, which filters capacitively coupled noise
22. Tips and troubleshooting189

Campbell CR310 Specifications

General

Brand	Campbell
Model	CR310
Category	Data Loggers
Language	English