LSI CDHT Series, User Manual

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3.1.4 Force and Length Zeroing (Initialization)
The force and length displays must be zeroed at a reference point. The normal reference for force is with the platforms
apart with nothing on the platforms or with the specimen spring on the lower platform. The normal reference for length
is with the platforms together or the hooks interlocked. To accomplish this initialization, make sure the stop rods permit
free travel of the upper platform and proceed as follows:
Compression
- After power up, move the upper platform fully up and press zero force so the force display reads zero.
- Move the upper platform to a position which touches the Lower Platform exerting a load of about 10 to 30 % of the testers
full scale.
- Press the Zero Length button to zero the Length Display.
Extension
- Install extension hooks as shown in Figure 6.
- Verify that the upper platform is at a position where Upper Hook interlocks with the lower hook, exerting a load of about
10 to 30% of the testers full scale.
- Momentarily depress the Zero Length button to zero the Length Display.
Figure 4
Compression Zeroing
Figure 5
Extension Zeroing
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