In order to reach 40 W injected into the ITF, as agreed in the PSL/INJ meeting, we changed the correction offset voltage of the AOM of the power stabilization loop.
We proceeded as follows:
- we opened PSTAB loop
- we unplugged the corrections (named out corr) at 14:13:50 UTC --> the power at the output of the PMC increased by 5%
- the potentiometer for the corrections was set to 8.5. We set it 0 and plugged again the corrections at 14:15:28 UTC
- we increased the corrections voltage step by step from 14:17:00 UTC to 14:25:00 UTC (1st plot)
- we verified from a trend that the minimum correction range needed is 0.85 Vpp (2nd plot)
- we set the offset on the potentiometer to 2.5 (14:52:22 UTC), to be in the range where the voltage effect is known. The 3rd plot shows the corrections and the error signal before and after this adjustmnet.