TestWare-SX Data Acquisition

A data acquisition process acquires data from one to eight input channels. This type of process should be sequenced in parallel with a command process. Meaningful data cannot be acquired unless the control channel is doing something.

How it works

A data acquisition process can be configured in a variety of ways. The following attributes may be combined primarily to trigger other processes, to acquire data, or a combination of both.

Select one of four data modes to define how data is collected.

Select one of five buffer types to define how data is recorded.

The process monitors a master channel according to the selected data mode. The master channel can be a sensor signal or time. A sensor signal can detect level changes or peaks/valleys. Time can acquire data at set intervals.

When the master channel detects the data mode requirement, data is acquired from the master channel and up to seven slave channels. Each channel of data can have different units assigned to it.

Data is acquired until a data buffer is full. A buffer's size and type determine how data is recorded and how it affects other processes.

More Information

The Data Acquisition Design window defines the following:

Sequences the process in a test template.

Assigns the master channel and selects any slave channels.

Selects the type of data to acquire.

Selects the type of buffer.

The Data Acquisition Parameters window selects units appropriate for the data type and assigns the size of the buffer for the master channel. It also assigns units to each of the slave channels.

You can find detailed information about this process in Chapter 6 of the 790.10 TestWare-SX Application Manual.


Data Acquisition Design Window

This window to specifies when the process starts and stops, and how it acquires data. The information in this window is saved with the test template.

Label

Names the process. Type the name you want to call the process in the entry field.

Mode

Selects one of the four types of data to be acquired.

The Peak/valley mode records data when the master channel signal detects a peak or valley. This mode looks for a peak before a valley.

The Valley/peak mode is the same as the peak/valley mode except it looks for a valley before a peak.

The Timed mode records data at specified equal time intervals. Time becomes the master channel.

The Level Crossing mode records data when the master input channel signal changes a specific amount.

Master Channel

Specifies the input channel that determines when data is recorded from the slave channels. Select an input channel or Time.

Buffer Type

Specifies how data is temporarily stored until the data is saved to disk.

Start Trigger

Specifies the beginning of the process. Press the list icon and select a trigger.

End Trigger

Specifies the end of the process. Press the list icon and select a trigger.

Slave Channels

Specifies additional input channels for data acquisition. Highlight each input channel to select it as a slave channel. Up to seven input channels can be selected. When the master channel acquires data, all slave channels also acquire data.

Buffer types

Since each type of buffer offers different characteristics, you may define one data acquisition process to simply trigger another data acquisition process to acquire data.

Single

Data is recorded to fill the buffer once, then stops the process and saves the data to disk. The size of the data buffer determines how much data to collect.

This selection acquires specific data in a test, and is useful for triggering other processes

Circular

In this mode, data is continuously taken and automatically stored to disk. Storing continues until the end trigger requirement occurs or the step done process is encountered. The only limit to the total number of samples is the drive_s storage capacity.

Continuous with Trigger

This buffer type functions the same as the continuous buffer except it issues a trigger each time the buffer if full. You specify the size of the buffer to determine when the trigger is issued. This process ends at the end of a step.

This selection is useful to trigger other processes at regular intervals while saving data

Trigger Only

This buffer type functions the same as the continuous with trigger  buffer except it does not save data. You specify the size of the buffer to determine when the trigger is issued. This process only ends at the end of a step.

This selection is useful to trigger other processes at regular intervals without saving data

Circular

A circular buffer continuously records data to the buffer. When the buffer is full, the data is loaded into the top again, overwriting the oldest data. This continues until there is an end trigger or the step ends and saves the data to disk.

This type of buffering is useful when the data just before some event (such as specimen failure) is crucial, but data is not required for the whole test.

More Information

You can find detailed information about this process in Chapter 6 of the 790.10 TestWare-SX Application Manual.

Go to How it Works for an overview of the process.

After you complete this window, you can double-click the name of this process in the Edit Template window to display the Data Acquisition Parameters window. This allows you to assign parameters to the default procedure.


Data Acquisition Parameters Window
Data Acquisition Parameters Window:

You must establish a data acquisition process with the Data Acquisition Design window before you can use this window. The information in this window is saved with the test procedure.

Data Header

Labels the data in the data file.

Sensitivity, Level Increment, or Time Increment

Specifies how data is acquired. The label for this field depends on the Mode you selected in the Data Acquisition Design window.

A sensitivity value specifies how much the master channel feedback signal must change to detect a peak or valley. The highest or lowest value is remembered (along with slave channel data) until the master feedback signal changes the specified sensitivity value, then the peak or valley data is recorded.

A level increment value specifies how much the master channel signal changes between data acquisitions. The increment level is referenced to zero and not from the beginning value of the process.

A time increment value specifies how long between data acquisitions.

Buffer Size

Specifies the number of data elements the buffer can store. A data element represents one data sample of the master channel and each slave channel.

Assign Report Units

This area of the window specifies the units for each master and slave channel.

Assigning report units

1	Highlight a channel in the Channel column. This causes the Units column to display the appropriate units for the dimension of the channel.

2	Highlight the units you want assigned to the channel data.

3	Repeat this procedure for each master and slave channel.

More Information

You can find detailed information about this process in Chapter 6 of the 790.10 TestWare-SX Application Manual.

Go to How it Works for an overview of the process.