When viewing a sensor trace in the ODiSI software, there are two functions that both appear to have similar effects: 'Save Tare' and 'Rekey'. While both appear to zero out the sensor, the actual functions are quite a bit different.
Tare
- A sensor can be zero-ed out before the start of a test. This re-zero-ing is called a Tare. Tares are specific to Gage Pitches.
Rekey
- Any sensor whose key has been installed in the software and is able to be identified can be rekeyed.
- Reasons for needing to Rekey include:
- Re-splicing a broken sensor
- Taking the sensor to higher strain ranges
- Re-centering the strain and temperature range around a new point
- Permanently removing strain gradients induced in the sensor. For example, if a strain sensor is installed and is loaded to 10,000 με prior to a test, the system will only be able to measure an additional 5,000 με. If the sensor is rekeyed, the sensor can then be used over a larger strain range.
- It is important to ensure that the sensor and system are static and in a quiet environment when Rekeying a sensor.
For more information, please see Sections 6.3.1 Sensor Tare and 6.3.2 Sensor Key of the User's Guide, accessed by clicking the '?' icon in the upper-right corner of the ODiSI software.