plots attched.
For the ITM it was basically a one click recovery (using Tcrappy blends and isolate level 3), I tripped the ETM trying to bring it up (I tried 750 blends and level 3 on stage 1, that didn't work).
Hugh saw that the biases on the EMT ISI were fairly small, and brough it to stage 1 level 3 with T crappy, stage 2 level 2 Tcrappy.
The microseism has been rising over the last 20 hours, and there was a big spike somewhere around 2 am. (we are currently at around 5 on the strip chart, I'm not sure what the units are).
The tripping may be due to the M6.9 earthquake in China (see LLO aLOG entry ) which occurred at about 3:20 AM CST (or 1:20 AM PST). It tripped all our watchdogs
(Alexa, Hugo)
ETMX watch dog tripped at 9:45am. Similar spikes seen in ISI.
What happened at 9:44am PCT: Fluid pressure drops on HEPI (No fluid pressure on MEDM screen of HEPI pump. reason still unknown). HEPI drive increases to meet targets, but hepi does not get physically driven due to the abscence of fluid pressure. The servo increase the output drive to compensate for it to the point where HEPI trips (1). Once tripped, HEPI slowly (hydrolic system) comes back to its floating position. While slowly coming back, it saturates the T240s, which are included in the blend which is fed to the ISO, causing the ISO of the ISI to ramp up as well, and trip the ISI (2), 2 seconds after HEPI tripped.
Trip times:
HEPI: 1076262292 (1)
ISI: 1076262294 (2)