I checked the status of the fiber noise cancellation.
When I requested the ENGAGE_TEMPLOOP, the decorator @woofer_range_check performed the lock loss.
That is the K1:ALS-X_FIB_WOOFER didn't touch the LIMIT of 5.0,
def is_woofer_locked():
woof = ezca['ALS-'+arm+'_FIB_WOOFER_OUTMON']
if (woof < 4.99) and (woof > -4.99):
return True
else:
return False
This situation happened both X and Y.
Just I left the memo for the status of FNC.
If my memory is correct, DGS outputs for woofers are turned off due to IOO RTPC trouble in this May ( https://klog.icrr.u-tokyo.ac.jp/osl/?r=36959 ). Strictly speaking, now wonders are applied 75 voltages manually. And DGS offsets are set to 0.
We need to enter PSL and to restore them
Komori, Fujimoto, Ootaki, Iizuka, Tanaka
As reported in the original post, FNCs could be locked because DGS outputs for woofer PZTs were turned off and woofers were applied with 75 V offsets manually due to the k1ioo1 trouble in this May (klog36959). We restored the situation to that before the trouble. Fig.1 shows each PZT driver status for each PZT. We found that tweeter PZT were applied with ~135 V. According to Hirose-san, at that time, she also applied the tweeters with 75 V manually. Then, she did not turned off the DGS outputs for tweeters. So after the recovery of k1ioo1, tweeters were applied with manual offsets + DGS ouputs. So we restored the manual offsets to 0 about all of PZTs. After that, we turned on DGS outputs for woofer PZTs. Fig. 2 show the PZT driver status after our work. Fig. 3 shows the timeseries of X or Y GR laser power at each fiber output on POP or POS. Around -5m, we performed the above work. GR Y power was restored (and improved) but the GRX was decreased. Therefore, we tweaked the alignment of the PZT mirror just before the fiber coupler (Gr M25 in PSL optical layout). Then, we restored the GRX power.
After coming back to Mozumi, we confirmed FNCs could be locked with guardians. FNCs could be locked (Fig.4). On the other hands, the fringe sizes of FNCs, especially FNC X seem to be lower than before (Fig.5). So we need to restore them. In this status, FNC X can keeps the lock ~2 hours and FNC Y can keeps the lock more than 4 hours.
