A loaded graphite cartridge was set in a tantalum boated and wrapped with 3 tantalum sheets (Friday May 22, 2020)
The set up was installed in the EVAP1 and pumped down during the weekend.
Heater (TGHT) tripped after being at 120A about approximately 10 min.
The pressure was below 500 mTorr when the trip occured (around 20 mTorr) . Pressure did not appear to have gone past 200 mTorr but was dropping fast at the time of trip.
Will try again tomorrow after consulting with Gelo.
Trying again while monitoring Power Supply reading ( Darwin Remotely and Marla onsite)
IGP1 = 7.7 e-7 Torr
Good vacuum = 1e-1 Torr
Bad vacuum = 5e-1 Torr
Current ramp is 1A per 10s from 0A to 120A
Wednesday, May 27, 2020, 10:49
Reached 120A on TGHT
TGHT= 0.92V
IGP1 = 3.6 e-06 Torr and rising
Wednesday, May 27, 2020, 12:46
TGHT = 120.2 A, 0.98V
IGP1 = 6.85e-6 Torr
Starting ramp at 3A per 10s up to 550 A or up to pressure drop start
Wednesday, May 27, 2020, 14:21
Heater tripped again at around 0.14 Torr and approx 440 A
Will start again hoping pressure stable enough to not trip heater.
Wednesday, May 27, 2020, 14:22
IGP1= 1.05e-6 Torr
Ramping to 120 A at 1 A per 10 s
Wednesday, May 27, 2020, 15:12
Starting ramp on TGHT at 3A per 10s up to 550A or pressure dip.
Wednesday, May 27, 2020, 15:35
Changed vacuum settings (paused ramp and restarted)
Good vacuum 1e-2
bad vacuum 5e-1
Wednesday, May 27, 2020, 16:30
TGHT = 549.4 A, 5.35V
IGP1= 2.1e-5 Torr
Reached 550 at approx 4 pm
Thursday, May 28, 2020, 00:31
IGP1= 3.31e-6Torr
TGHT = 549.3 A, 5.45V
Initiate ramp down at 2 A/min to 0A
Reduced cartridge was dismounted Friday, May 29, 2020 and transferred to Glove box.