Measurement Computing LogBook Series - Manual (Page 18)

1-8 An Introduction to LogBook 969591 LogBook User’s Manual
System Software
LogBook software includes LogView, Upload Scheduler (optional) and a post acquisition data analysis
application such as eZ-PostView. A synopsis of each application follows.
LogView is a ready-to-use Windows-based program for data acquisition and logging. The program
provides a means of selecting channels, gains, transducer types, and various parameters. After setting
up the configuration on the PC, you must download the configuration file to LogBook’s PC-Card.
LogBook then uses the PC-Card to start the pre-configured acquisition. During an acquisition,
LogView can display channel values on its Graphical User Interface in the form of a spreadsheet,
bargraph, analog meter, or digital indicator. LogBook data can be uploaded to your PC in various
data formats (Excel™, SnapMaster™, MATLAB™, DASYLab™, Lotus ® , Quattro, and ASCII) for
compatibility with virtually all post-acquisition analysis software.
Upload Scheduler is an application that exists as part of the LogBook/Modem option. Upload
Scheduler allows you to configure upload events for one or more LogBooks. A scheduled event can
be configured to execute one time, or periodically, with no post-configuration intervention by the
user. The Upload Scheduler is detailed in chapter 7, Using Modems and the Upload Scheduler.
Post Acquisition Data Analysis programs provide a means of viewing and analyzing data via
interactive graphics. Refer to the document module for detailed information. The post data analysis
programs are discussed in an independent document. PDF versions of the documents are loaded on
to your computer’s hard drive during software installation. The default location for the files is the
Programs group, which is accessible from the Windows Desktop.
Operational Features
Data Acquisition Overview
Note: Acquired data is signal-conditioned before it is logged (recorded by LogBook). The data can be
post-processed via analytical programs.
A Sensor/Transducer reacts to a physical quantity (such as stress, strain, frequency, temperature,
acceleration, light intensity, etc) and encodes that quantity into an analogous electrical signal. A wide
variety of transducers produce signals that vary in type and strength—some generate a voltage; others alter
an electrical property. As the measured condition changes, the analog sensor signal can vary directly or
inversely and in a linear or non-linear way.
Although LogBook can read volts directly, many sensor types still require signal
conditioning before they can be correctly interpreted.
The Signal Conditioner changes the raw transducer signal into a voltage for use by
LogBook’s Analog-to-Digital Converter (ADC). Depending on signal quality, several steps may be
involved (e.g., linearization, isolation of high voltages, amplification of weak signals, attenuation of strong
signals, filtering of noise and irrelevant frequencies, differential voltage measurement, simultaneous sample-
and-hold, and pulse/current-to-voltage conversions). DBK option modules are designed for conditioning a
particular type of transducer signal. The signal conditioner’s output voltage range is ―normalized‖ to a
user-selected range for the measured values.
Note: Multi-channel DBKs can multiplex several input signals into one of LogBook’s 16 main inputs.
Multiplexing up to 16 analog channels for each LogBook main channel allows system expansion
up to 256 analog input channels.