MTS Series 311 Load Frame - Manual (Page 81)

Load Unit Addendum Addendum 81
For load units with hydraulic lifts and locks, the crosshead can slowly drift
down the columns if the locks are turned off and when hydraulic pressure is
turned off.
The crosshead can damage any test fixtures, grips, and specimen in its
path.
Unlock the crosshead only to reposition it. Always lock the crosshead after you
have repositioned it, and never leave the crosshead unlocked.
2. Set the crosshead position.
The crosshead position depends on the length of the specimen being tested,
the starting position of the actuator, and the size of the fixtures or grips
being used.
3. Install the specimen.
Specimen installation varies according to the type of grip being used. See
the appropriate grip manual for installation instructions. Each type of grip
requires the specimen or specimen fixture to fit properly into the grip. You
should always review specimen installation procedures found in any grip
product information manual.
Before testing, ensure both grips are clamped and the specimen is secure.
An insufficiently gripped specimen can cause specimen damage, equipment
damage, and the possibility of specimen fragmentation.
4. Set up the load frame for testing.
A. Set the actuator velocity limiting switch to (full flow).
B. Disable the handset and set up the controller for system operation.
5. Reset the controller interlock.
6. Apply load unit station high hydraulic pressure.
Handset Control
The handset has an encoder and buttons to help you during specimen installation
and test execution. The handset also has an alphanumeric display and LEDs to
provide feedback.
CAUTION
CAUTION