TestWare-SX External Command

An external command process uses a signal from an external device to control a servovalve or servomotor. This process should be sequenced in series with other command processes.

Prerequisites

You must perform the following before you can use this process:

Connect the command source to the digital controller.

Define the command source input signal and control mode.

Set up a temporary sensor to scale the input.

How it works

This process lets you use a command source connected to the rear panel of the digital controller to command the servo loop. You must start the external command source before your test reaches the external command process. When the external command process begins, it ramps to the mean level setting of the process. Since the external command is at an unknown level, an amplitude ramp ensures that you achieve smooth transition from the current command to the external command.

More Information

The External Command Design window names the process and sequences it in a test template.

The External Command Parameters window defines the control mode, mean level, mean level ramp time, and amplitude ramp time.

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


External Command Design Window

This window specifies when the process starts and stops. The information in this window is saved with the test template.

Using the window

Use this window to designate a single test command process in a step.

1	Name the process with the Label entry field.

2	Select a Start Trigger to sequence the process. This process should be sequenced in series with another command process.

3	Select an End Trigger to stop the process. Use the default none trigger if you want the process to complete without interruption.

4	Select a Control Channel for the process.

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 External Command Parameters window. This allows you to assign parameters to the default procedure.


External Command Parameters Window

You must create a external command process in a template with the External Command Design window before you can access this window. The information in this window is saved with the test procedure.

Initial Ramp Time

Specifies the amount of time the command ramps from starting level of the process to the mean level setting. Enter a ramp time.

Amplitude Ramp Time

Specifies the amount of time the program amplitude ramps from zero to full-scale The ramp rate value represents units per second. This slowly applies the program command to the specimen when the program starts. This feature prevents sudden actuator movement when the external command starts.

Control Channels

Displays a list of the control channels selected in the Design window. Each control channel can have different paramters.

Control Mode

Selects the control mode for the external command.

Mean

Sets the mean level of the external command.

Multiplier

Specifies a multiplication factor to scale the incoming signal. This establishes the span (peak-to-peak amplitude) of the external command. The multiplier value scales the external command signal as a percentage of full-scale.

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.