This morning I continued pumpdown of EX after the TMDS exercise yesterday, using the two mobile ISP1000 scroll pumps.
| Starting Pressure: 5.35 Torr | Start Time: 8:32 am |
| Turbo Crossover Pressure: 500 mtorr | Turbo On: 10:52 am |
| Ion Pump Opening Pressure: 1.1E-7 Torr | Ion Pump On: 3:12 pm |
The turbo reached full speed in ~30 minutes and I transitioned the backing pumps from the ISP1000s to the single ISP250 on the turbo stand once the turbo inlet pressure was <1E-5 Torr.
The cooling water was adjusted on the turbopump stand so that the pump and controller pressures were <= 40C.
The chamber pressure quickly reached low E-7 Torr range, so I opened up the ion pump (IP12) to assist with high vacuum pumping.
I also turned off the EX cleanrooms at Sheila's request at ~1:35pm.
We will still need to leak check the small 2.75" CF blank we installed where the TMDS ionizer attaches before we can open up GV20. EX volume will pump with both turbopump and ion pump over the long weekend.
