Wednesday, May 04, 2022, 09:42

Yesterday, a second graphite cartridge was installed in EVAP1, it consists of the old, 3-body cartridge design, and was sanded on the outside to be able to fit a P2N container. 

First I tried ramping manually, but the heating tripped because pressure was too high.

Then the parameters were set as previously, but it tripped again

IGP1= 2e-5 Torr

Good vacuum 8e-2 Torr

Bad vacuum 5e-1 Torr

Autoramp set to 1A/10s to 500A

Autoramped up to 700A @ 1A/10s. 

Wednesday, May 04, 2022, 11:40

Another ramping trial, with different heating rate:

IGP1= 3e-5 Torr

Good vacuum 8e-2 Torr

Bad vacuum 5e-1 Torr

Autoramp set to 1A/20s to 700A

Autoramped up to 700A @ 1A/20s.  

Wednesday, May 04, 2022, 15:50

IGP1= 3e-2 Torr

Good vacuum 8e-2 Torr

Bad vacuum 5e-1 Torr

Autoramp set to 1A/20s to 730A

Autoramped up to 720A @ 1A/20s.  

Pressure dropping while current is increasing at autoramp rate.

Wednesday, May 04, 2022, 16:10

From 730A, once the pressure went down to ~1E-3T, the current was suddenly raised to 750A and 770A to see if significant pressure increase was noticed, but small bumps reaching 1.5E-3T were not considered a sign of further reduction.

The rampdown started from a pressure ~1E-3T, from 770A to zero with rate 2A/10s