With Fujii-kun.
This post is related with entry 7066. Is related to the investigation of the large drift of the suspension, especially in F0.
Fujii-kun notifed that the calibration factor of the F0 LVDT seemed unusual. I checked the original Excel file and I have found the factor (2.174 µm/cnt) to be incorrect. I have the following comments:
- The plot was made with the keystone position data formated as text not as numbers. That's the reason the data in the horizontal axis does not show the correct data.
- It also happens that the axes labels are the other way around. Nevertheless, the calibration factor which was written in the medm screen was calculated considering the keystone position in the horizontal axis and the LVDT output in the vertical one.
After the correction I got a calibration factor of 1.1285 cnt/µm, which becomes 0.8861 µm/count for the medm screen. This value has been corrected in the medm screen already. On December we will have access to the suspension and we should double check the offset value.
