Cooper Instruments & Systems Dytran 5340 USB Triaxial Accelerometer - Manual (Page 11)

REV B 10/18/12, ECN 8972
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11. Data Integrity Indicator
The Data Integrity box indicates one of three conditions: OK , Overflow, or Checksum Failure .
An overflow condition occurs when system resources are inadequate to sustain data
processing at the selected bandwidth. This might be due to CPU speed, insufficient free
memory or cpu/memory ‐ intensive processes running concurrently with the VibraScout™
application. An overflow indicates a loss of some data samples. The condition can usually be
eliminated by selecting a lower bandwidth. A Checksum Failure indicates a fault in USB
communication. If this occurs, check the cable connection between the 7543A and the PC.
12. Clear Button
The Clear button clears the plots and the min, max, mean values. Plots are automatically
cleared at the start of every acquisition.
13. Plot Vertical Axis Scaling
Range and Offset values for each axis can be specified or Auto‐scaling can be selected to
adjust the scale when an acceleration value exceeds the current range.
14. Absolute and Relative Mode
In Absolute mode (Abs) , acceleration data are shown relative to the earth's gravitational field
using the factory calibration. In Relative mode (Rel) , the acceleration offsets are subtracted
from the data using user selected Offset values acquired in the Configuration screen. See #6
Offsets in the Configuration section.
15. Log to File
Data File logging is enabled/disabled by the checkbox. The name of the data file and related
parameters are first specified in the Configuration screen. If no data file is specified in the
Configuration screen and this check button is selected, a data file prompt menu will pop up
requesting a new data file to be created.
16. FFT
The frequency spectrums of the three acceleration axes are calculated and displayed by
clicking the FFT button. The FFT is performed on all plot data. FFT plots can be displayed in
Linear or Log format and the displayed frequency range is selectable. The maximum
selectable frequency is equal to 1/2 the sample rate.