chandra.romel@LIGO.ORG - posted 12:18, Wednesday 02 May 2018 - last comment - 12:21, Wednesday 02 May 2018(41792)
CP4 bake ramp down
This morning Ken D. de-energized the additional 10 kW heater in the CP4 bake enclosure by simply switching the breaker off inside the panel. This supplemental heater did not seem to hinder the termperature profile - the original 20 kW heater ramped up from 20% output to 40% output (note: before we added insulation, we could not ramp past 100C without this added heat due to leaks). Also this morning MCE fixed the ramp software by removing the limit programmed in during testing on Monday. Lost some heat in the process; soak set point is 110C (to match TC#4) - will ramp to that, soak for 1 hr and then start ramp down.
Here it so round two of ramping down at 1C/hr.
While I was at MY VEA, I noticed APS reps traveling in and out of VEA several times to access emergency exit. Two MY gauges tripped sometime this morning but came back on quickly, probably because pressure is relatively high near CP4 due to warm beam tube metal.