MTS Axial Extensometers - Manual (Page 53)

Installation 53
1. Zero the arms of the extensometer. Depending on the extensometer,
this can be accomplished using the zero pin, stop block, or a special
fixture.
2. Hold the extensometer so that its knife edges contact the specimen.
3. Secure the upper arm around of the extensometer the specimen.
• If you are using an anchored spring mount, clip the spring
around the specimen. If you need to change the anchor
position, see the appropriate procedure.
• If you are using a sliding spring mount, see the appropriate
procedure.
• If you are using extension springs, connect one end of the
extension spring to the hook attachment of the upper arm. Use
the small utility hook to grab the other spring and pull it
around the specimen to the other attachment hook.
• If you are using an elastic band, connect one end of the elastic
band to the hook attachment for the upper arm. Use the small
utility hook to grab the other elastic band and pull it around
the specimen to the other attachment hook.
4. Repeat Step 3 for the lower arm of the extensometer.
5. Zero the extensometer’s output.
A. Remove the zero pin, fixture, or release the zero stop.
B. Check the extensometer output at your controller.
C. If necessary, zero the extensometer output at your controller.
About Quick Attachment Springs
Quick attachment springs hold the extensometer onto the specimen with
a pair of special springs that clip around the specimen (see the following
figure).
Each extensometer is provided with one spring set for round specimens
and two spring sets for flat specimens (one spring set with a short spring
length and one spring set with a long spring length).
Quick attachment springs can be adjusted to accommodate different
specimen thicknesses. They can be adjusted by sliding the spring in or