terra.hardwick@LIGO.ORG - posted 20:58, Saturday 23 July 2016 - last comment - 21:25, Saturday 23 July 2016(28600)
PI at 50, 60 W today
Kiwamu, Carl, Terra
18041 Hz (ETMY) successfully damped through several locks. 15542 Hz (ETMX) unstable after about 1 hour at 50 W but we cannot damp without going to LOWNOISE_ESD_ETMY.
We had a few ~1 hour locks at 50 W today, with a bit of time at 60 W.
18041: damped first with +30 phase, +30K gain but rang up in the second lock despite. Changing to zero phase damped it in the second lock and prevented any ring up during the third lock.
15542: rings up almost immediately at 60 W. Rings up after an hourish at 50 W. This mode belongs to ETMX but we've been sitting at INCREASE_POWER during locks so we cannot use the LNLV ETMX driver to damp.
The SUS_PI guardian is running again. It had got stuck with spm differences after the model restarts.
During these lock stretches settings for damping several modes were found and put in the gaurdian.
15522Hz ITMX (mode2) was ringing up at the end of the last lock aand was damped with gain -300 and phase -60 deg.
15541Hz ETMY (mode25) was stable but the driven up to find a damping gain 1000 and phase +60deg and the
18041Hz ETMY phase has been adjusted to 0 deg (gain stays 1000)