Laura Lambert wrote: |
Thursday, April 27, 2017, 14:01
Target container contains 470 discs of SiC
Target packed length = 16cm.
Mass of SiC(green) = 52.13g
Discs in target are arranged as follows: 5singles / 1pack / 65singles / 1pack / 75singles / 1pack / 75singles / 2packs / 75singles / 1pack / 75singles / 1pack / 55singles / 1pack / 5singles
Container is wrapped with 1x heatshield around each side of cooling fins; no end caps are inserted yet - coated spring inserted both sides to hold discs in place.
Sintering temp = 1800C
Chamber is currently being pumped down.
Friday, April 28, 2017, 13:06
HS water valves turned on this morning, no leaks detected.
Tapped up manually to 40A
Waited ~3hrs , vacuum stable.
IGP1 = 4.13e-6 Torr
Initiating auto-ramp at 0.2A/min and 0.1A/min for the TGHT and TBHT respectively.
TGHT max = 400A. TBHT max at 230A.
Slope on OMEGA = 1.08 [see elog i.d. # 326 for reasoning behind OMEGA slope choice]
Tuesday, May 02, 2017, 09:24
IGP1 = 2.34e-6 Torr
TBHT = 230A, 3.15V
TGHT = 298A, 3.96V
OMEGA = 1030C
Vacuum stable, increasing ramping rate up to 0.5A/min
Tuesday, May 02, 2017, 13:20
IGP1 = 1.3e-5 Torr
TGHT = 400A, 5.6V
OMEGA = 1175C
Increasing max setpoint to 500A
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Wednesday, May 03, 2017, 13:33
TGHT had remained at 500A for 16hrs, vacuum had initially come down nicely.
Vacuum was starting to creep up when i came in this morning before 8am, IGP1 was at 1.2e-5 Torr
TGHT = 500A, 7.77V
OMEGA = 1440C
Around 8:30 vacuum started to spike, so the TGHT was tapped down rapidly to 450A
Tapping the TGHT down made no difference to the vacuum.
By the time 450A was hit, it was too late and the spike in vacuum caused the evaporator to trip off.
Turbo pump in epics showed on, turbo pump showed on according to TP direct controls.
Everything was shut off and the venting tapped, this made it obvious the turbo pump was already off as there was no ramping down noises from the turbo pump.
TP control box turned off then on again, at this point the controls showed a 'fail' message.
Turns out the turbo pump control box was fried and that's what had caused the turbo pump to fail with no notice in epics causing the vacuum to spontaneously spike.
Waiting on a new one from vacuum group...
See photos attached of striptool screenshots.
Wednesday, May 03, 2017, 15:03
New TP control boxed installed.
Turbo pump turned on, everything pumped down.
Vacuum good, IGP1 = 6.92e-7 Torr.
IGP2 still not working, won't turn on via epics.
Tried unplugging and plugging back in...still appears red with 'fail' message...
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