We left the air compressor (in chiller yard) off and valved out all night, with only the compressed N2 bottle feeding the four pneumatic gate valves in corner station. This morning the bottle pressure is quite low i.e. consumption/loss is high. We have some ideas to improve this but need LVEA access first.
At 8:36 am (16:36 UTC) I turned air compressors back on and valved in to corner building (but not LVEA). Before we start receiving alarms on PT199, I will valve back into LVEA, and request DetChar to look at data again to confirm correlation between noise and air compressor turned ON/OFF, but not valved into LVEA.
Nov. 14 (UTC - locked)
18:01 - turned compressor OFF
Nov. 15 (UTC - locked)
0:12 UTC - turned compressor ON
1:30 UTC - turned compressor OFF
16:36 UTC - turned compressor ON
17:26 UTC - valved in compressor to LVEA (after losing lock)
With bottle pressure falling fast (300 psig), we valved in air from compressor to LVEA at 9:26 am local (17:26 UTC). Spreadsheet attached.
Kyle and I entered LVEA during lock loss to adjust valve pressure regulators. GV7 will not rise beyond 60 psig. The others match the supply (~66 psi). Next opportunity we will squirt SNOOP at joints to leak hunt.
I've translated Chandras changes into times where we see things in gw-strain, and what we see in accelerometers.
So the accelerometers [second attachment] don't seem to care if the Compressor is valved out.
In the GW-strain we see something when you turned the compressor on at 00:12 UTC, until it was turned off; But then when you turned it on for the second time, I can't conlcusively say we see something. Our range is a bit low right now, so maybe we are just a bit more noisy than usual and the noise peak is buried below that.