Extensometers - Operating Notes - Instron 4400 Series Operator's Manual

Strain Calibration
(l) Press ENTER. After 3 seconds, the STRAIN BAL
LED goes out and the balance function is completed.
Strain Gauge Extensometers - Operating Notes
The strain measuring accuracy of a Series 4400 system
is 0.5% of the strain reading, ±1 count, on the display or
the analog output to recorder (± linearity of transducer).
This specified accuracy is valid from the calibration
point of an extensometer down to 2% of maximum
strain (displacement). An extensometer must be recali-
brated if the ambient temperature goes outside the range
of +10 to +38°C (+50 to +100°F) after initial calibration.
After the extensometer has been installed on the speci-
men, secure the cable so it does not interfere with the
movement of the extensometer. Also, keep the cable
away from the drive motor housing to avoid electrical in-
terference.
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