Measurement Computing DataShuttle - Manual (Page 38)

3-2 Introduction to the DynaRes 11-09-01 DataShuttle and DynaRes
You can measure temperature, for example, by selecting from among 11 different thermocouple types, or
from a variety of resistance temperature detectors – RTDs. With our application software, the process
simply consists of selecting the type of sensing device from a menu – the driver automatically handles cold
junction compensation and linearization.
Data Presentation
The combination of our hardware and application software (DASYLab® or QuickLog PC) enables both the
display of data on the screen, and the logging of data to disk for later analysis.
The system is capable of showing data on the monitor in a variety of formats, including graphical meters.
Charts can indicate trends for comparison of actual measurements on several channels, or for setting data
points or alarms.
Dynamic Resolution
Your DynaRes incorporates “Dynamic Resolution,” improving the board’s accuracy.
With this feature, resolution is greater at the lower (negative) end of any range than at the higher end. As
your readings approach the low end of any given range, the resolution becomes finer (that is, the increments
of the signal you can distinguish become smaller).
This feature allows you to obtain the same advantages of an integrating converter, with the speed of a
sample and hold converter, but without its susceptibility to noise.
Dynamic resolution gives a resolution that is a fixed percentage of the input voltage (not full-scale voltage)
down to about 10% of full scale. Our products, consequently, are the best available for taking accurate
measurements of low-level signals, as you would using a thermocouple sensor.
Dynamic resolution is always best toward the negative end of any range:
Dynamic Resolution for Dissimilar Ranges
Two vertical black “rulers” (range A and range B) portray the impact of Dynamic Resolution. Their
graduations – representing their ability to resolve – are always finer at the lower (more negative) ends of
their ranges, regardless of the spectrum of values the ranges are measuring.