MTS Systems Landmark 370 Series, Operation

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Key Concepts
Landmark™ Test System Operation 49
Basic Closed-Loop Control in MTS Landmark Systems
1. You input a compressive command by adjusting the Manual Command slider control in the
Station Manager application.
2. The Station Manager application (program source) instructs the digital controller to generate a
signal that represents the direction and amount of force the actuator needs to apply to the
specimen to accommodate your command.
3. The digital controller generates this command and sends it to the servovalve. The servovalve
spool opens and allows more high-pressure hydraulic fluid (from the Hydraulic Power Supply)
to push on the actuator that is attached to the lower grip.
4. The actuator moves and compresses the specimen.
5. The force transducer (load cell) senses the amount of compression and sends this feedback to
the digital controller, where it is compared with your command.
The system automatically repeats Steps 2 through 5 until the desired command is achieved. The digital
controller continues to generate commands to the servovalve to maintain the commanded force on the
specimen.