MTS TW Elite - Manual (Page 75)

• You will not be able to use any of the monitor displays in the Variable Views category (or other monitor
displays that use variables). You will only be able to use monitor displays in the Signal Views category,
such as the Signal Meter and Signal Scope.
• The charts and tables in the Review tab, which are based on variables, will not contain useful information.
• You will not be able to show test data in charts and graphs using the MTS Reporter Add-in for Excel.
Acquiring Data in a Continuous Stream
For typical tensile tests, you configure data to be acquired in a continuous stream using the Go To + DAQ
+ Detection or Dwell + DAQ + Detection activities.
For “multi-cycle” tests, you configure data to be acquired in blocks.
About blocks
Block boundaries are typically divided according to command content. This is sometimes loosely referred
to as “cycles” of data, though the blocks could be a group of ramps, ramps and cycles, or a custom
waveform.
Acquiring Data in Blocks Without Mode Switching
If you want to acquire data in blocks without performing control mode switches within the blocks, you can
use either the Custom Waveform + DAQ or Cycle + DAQ activities.
Acquiring Data in Blocks With Mode Switching
If you want to acquire data in blocks that include command elements that switch control mode within the
blocks, you need to use the generic Data Acquisition activity in parallel with a While Loop activity that
includes the command activities and increments the block count.
In this scenario, you must set up custom blocking using the Configure properties. To emulate the automatic
blocking performed by the Custom Waveform + DAQ or Cycle + DAQ activities, you need to configure
a variable that counts two segments (one cycle equals two segments).
Setting Buffer Size
You choose the buffer size by clicking the Advanced button on the Data Acquisition Properties page.
The default buffer size is set to 100. There are instances when this is too large. Symptoms that the buffer
size is too large include:
• Calculations do not run in a timely manner.
• Monitor displays do not update as often as necessary.
Recommended
While many factors determine ideal buffer size, observe the following:
• When acquiring data in a continuous stream, it is good practice to set the buffer size relatively high, so
that the buffer fills every 0.1 to 1.0 second.
• When acquiring data divided into custom blocks, it’s good practice to set the buffer size relatively low,
so that it accommodates the anticipated size of the blocks.
MTS TestSuite | 75
Design Guidelines