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Tuning the displacement control mode, Tuning the displacement control mode 71 – MTS Series 793 User Manual

Page 71

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How to Manually Tune the Control Loop

MTS Series 793 Tuning and Calibration

Tuning Procedures

71

Tuning the Displacement Control Mode

A displacement control mode uses the feedback signal from an LVDT (linear
variable differential transformer). You do not need a specimen to tune a
displacement control mode.

When to tune

A displacement control mode typically needs to be tuned only when recalibrated.
However, you may want to retune the displacement control mode if:

The fixtures attached to the actuator have changed (such as grips). The main
tuning factor is a change in the mass attached to the actuator.

Any time hydraulic system potential has changed, such as after servovalve,
hose, or pump replacement.

You want to fine tune the control mode.

The sensor range has changed.

You feel system response should be improved or reduced.

Prerequisites

Be sure the following conditions are present before you begin tuning the
displacement control mode:

Hydraulic pressure is off

The specimen is not installed

Procedure

This basic displacement tuning procedure should work for most applications—
consider it a guideline. You should be familiar with the background information
presented in this chapter so you can modify the following procedure for your
specific system.

1. Select the Tuning access level.