MTS Acumen - Manual (Page 82)

Note: The preceding illustration shows settings typical for a through-zero test. Note that these
settings differ from the Example Test, which is a compression-compression test.
Fixture Limits
Fixture limits are generally the widest limits. There are fixture limits for both displacement and force. Each
of these are set on the left side of the virtual machines found in the Situational Awareness panel.
Station Fixture Limits
Fixture displacement limits prevent actuator movement that could damage fixturing. To set fixture
displacement limits:
1. Ensure that the actuator is in the proper position for the test. For through-zero testing, the actuator
should be at mid-stroke. For tension tests, the actuator should be near full extension. For compression
tests, the actuator should be near full retraction.
2. Once the actuator is properly positioned, position the crosshead so that there is just enough room to
install the specimen.
3. With both actuator and crosshead properly positioned for the start of the test, calculate the remaining
stroke and determine the distance to first contact.
4. Using the fixture displacement limits found on the left side of the virtual machine in the Situational
Awareness panel, set the limit so that it trips before the actuator makes contact.
Fixture force limits correspond to the amount of force your fixturing can withstand without damage. Often
times the load cell has the lowest force capacity. For example, if the load cell has a force capacity of ±500
N, you should set your fixture force limit for ±500 N. Fixture limits are set on the left side of the virtual
machine in the Situational Awareness panel. It is common practice to always set fixture force limits.
82 | MTS Acumen ™
Key Concepts