| Miniproposals | ||||||||||
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| Operators | |
| Session leader(s): | Joseph Snipes |
| Physics operator(s): | Earl Marmar |
| Engineering operator(s): | Vinny Bertolino |
| Engineering Operator Run Comment |
| gas fueling and recycling |
| Session Leader Plans |
| Physics Operators Plans |
| Session Leader Summaries |
| Physics Operator Summaries |
| Entered: Jul 7 2004 04:36:50:440PM |
| Author: To Be Determined |
| 931007 Wall loading, recycling SL Snipes PO Marmar EO Bertolino ECDC overnight in He. Base Pressure = 1.0e-7 before run (with Cryo-pump on). RGA showing mostly D_2, HD, H_2, a little 20 & 18. D_2 fill and pulse Until shot 18 we were fighting the PLC current limit on OH2, which was set to 20 kA while were were asking for about 21. It appears that the subsequent duds and late breakdown fizzles correlate with small changes in B_Z at around 5 milliseconds. 1 Pfill=1.2e-5 D_2Nearly went; problem at about 30 ms. fizzle 2 attempt again; good breakdown; hards late plasma 3 More gas; fewer hards plasma 4 Added gas and extra pulse at .65 s plasma 5 slight B_R excursion? dud 6 minus_1_volt to 0 from -1e-3 to add 1 mT B_R; plasma 7 More gas, bigger late pulse; double integral gain on Z_cur, fizzle halve proportional gain after .5 seconds; slightly lower B_R? 8 P_fill to 1.1e-5, try again. Engineering tree turned off by E-dud mistake. No power supplies. 9 Turn Engineering tree back on. Good shot. plasma 10 Add more pulsed gas; late breakdown fizzle 11 Change minus_1_volt to +5e-4; very late breakdown fizzle Horne fiddled with Z_cur gains - now have D (.5 at .5 s), P (.2 at .4 s), I (.5 at .3 s). 12 Change minus_1_volt to -1e-3; good plasma 13 Z_cur integral gain to 3 from 5; move 2'nd gas puff to .5 s fizzle lower Argon puff; ok breakdown; B_R problem? 14 increase Prop gain on B_R to 5 from 2; lower fill to 1.0e-5 dud 15 changed OH2 voltage demand before 0 s, Increase ZXR gain plasma from 5 to 7; P_fill to 1.2e-5; minus_1_volt to -2e-3 16 Reduced Z_cur Integral gain to 1.5; p_fill = 1.1e-5 plasma 17 Repeat. fizzle 18 discovered that PLC current limits for OH2's were at 20 kA; PS dud set them to 25 kA; OH2U tripped at -.37 s 19 lower EF2L Prop gain to .5 at .2 s; got OH currents; B_R fizzle slightly positive; weak flash 20 minus_1_volt to -3e-3; Over correction to B_R, slight B_Z? dud 21 minus_1_volt to -2.5e-3; add -15 Amp to EF4; short shot; plasma lost vertical control after .2 s 22 reduced RXL prop gain; raised EF2L gain so it now comes down dud in steps after .2 s; P_fill = 1.1e-5 23 raise fill to 1.2e-5 dud 24 add -15 A to EF4; good plasma 25 reload pulsed gas from shot 3, but extend out to 0.6 s plasma some hards late; pellet at 1 s, disrupt on rampdown 26 repeat; late breakdown fizzle 27 repeat; good; hards late plasma 28 load pulsed gas from shot 9, but remove second pulse and dud turn off at .58; pellet at .6; B_z seems to be getting us 29 tweak OH1 Voltage before 5e-3s (was -80 V, now -100 V) plasma 30 tweak OH1 voltage again; now -120 V dud 13 plasmas, 8 fizzles, 9 duds |
| Session Leader Comments | |||
| Oct 7 1993 09:52:09:590AM | Joseph Snipes | Run Plan
Today's run is an investigation of the particle confinement versus density at constant current of Ip=600 kA, BT=5.2 T. We will start at low density and work upward in density throughout the day. In particular, by cutting off the gas puff during the flattop of the current, we will be able to measure the particle confinement time from the fall of the density. As the recycling changes during the day, the density behavior will also change. We attempted baking the machine at 60 C and running ECDC in helium until 4:00 a.m. Then both were stopped to allow the residual gases to pump out and to allow the machine to cool. The wall temperature was set to 35 C for the run. In fact, the heating only got to 50 C during the night due to problems with overheating at A port. | |
| Oct 7 1993 09:54:00:500AM | 931007001 | Joseph Snipes | Starting with low gas puff and prefill of 1.2 x 10-5 Torr. Programming
copied from 931006025, except for no H puff and reduced D puff. |
| Oct 7 1993 09:54:46:550AM | 931007002 | Joseph Snipes | First shot fizzled. Shot 2 went with hard x rays.
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| Oct 7 1993 09:56:08:860AM | 931007003 | Joseph Snipes | Shot 3 was about the same with hard x rays despite increased gas.
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| Oct 7 1993 09:51:40:480AM | 931007004 | Joseph Snipes | Run Plan
Today's run is an investigation of the particle confinement versus density at constant current of Ip=600 kA, BT=5.2 T. We will start at low density and work upward in density throughout the day. In particular, by cutting off the gas puff during the flattop of the current, we will be able to measure the particle confinement time from the fall of the density. As the recycling changes during the day, the density behavior will also change. We attempted baking the machine at 60 C and running ECDC in helium until 4:00 a.m. Then both were stopped to allow the residual gases to pump out and to allow the machine to cool. The wall temperature was set to 35 C for the run. In fact, the heating only got to 50 C during the night due to problems with overheating at A port. |
| Oct 7 1993 10:01:17:670AM | 931007004 | Joseph Snipes | Shot 4
Did much better with increased gas. Very little hard x rays. |
| Oct 7 1993 10:01:50:010AM | 931007004 | Joseph Snipes | Shot 5
Fizzle. Need to increase Br by 1 mT or so. |
| Oct 7 1993 10:02:52:200AM | 931007005 | Joseph Snipes | Shot 5
Fizzle. Need to increase Br by 1 mT or so. |
| Oct 7 1993 10:19:08:060AM | 931007006 | Joseph Snipes | Shot 6
Good shot! Gas puff at 0.62 s shows up clearly on H alpha, density, etc. |
| Oct 7 1993 10:28:27:190AM | 931007007 | Joseph Snipes | Shot 7
Raising final gas puff and reducing its duration a bit. Also increasing early gas to raise the density level. Fizzle! |
| Oct 7 1993 10:51:46:490AM | 931007008 | Joseph Snipes | Shot 8
No power supplies! Finger trouble. |
| Oct 7 1993 11:10:14:980AM | 931007009 | Joseph Snipes | Shot 9
Good shot. |
| Oct 7 1993 11:13:32:870AM | 931007010 | Joseph Snipes | Shot 10
Raising the gas early to try to raise the density again. Fizzle! |
| Oct 7 1993 11:38:50:550AM | 931007011 | Joseph Snipes | Shot 11
One more time . . . Fizzle! |
| Oct 7 1993 12:01:38:660PM | 931007012 | Joseph Snipes | Shot 12
One more once . . . Decent shot, disrupted late. Perhaps the density is too high as the current ramps down. |
| Oct 7 1993 12:07:24:380PM | 931007013 | Joseph Snipes | Shot 13
Moved late gas puff to 0.5 s to reduce the density during the current decay. Fizzle! |
| Oct 7 1993 12:45:40:500PM | 931007015 | Joseph Snipes | Shot 14
Lowered prefill to 1.0 x 10**-5 Torr. Also changes in Br proportional gain from 2 to 5. Dud. |
| Oct 7 1993 12:51:47:000PM | 931007015 | Joseph Snipes | Shot 15
Good shot. |
| Oct 7 1993 01:05:01:160PM | 931007016 | Joseph Snipes | Shot 16
Took out late gas puff to start at an equilibrium density. |
| Oct 7 1993 01:11:30:070PM | 931007017 | Joseph Snipes | Shot 17
Fizzle! |
| Oct 7 1993 01:36:59:270PM | 931007018 | Joseph Snipes | Shot 18
One more time . . . Dud. Power supply problems. It seems that the current limit on OH2 was set to 20 kA when we asked for 21 kA. So, the feedback was ineffective. |
| Oct 7 1993 02:06:56:000PM | 931007019 | Joseph Snipes | Shot 19
Fizzle! |
| Oct 7 1993 02:20:11:970PM | 931007020 | Joseph Snipes | Shot 20
More tuning of Br to try to improve the current rise at breakdown. Fizzle! |
| Oct 7 1993 02:26:09:580PM | 931007021 | Joseph Snipes | Shot 21
More tuning of Br and Bz to try to improve the current rise at breakdown. Extended gas puff out to 0.8 s. Got plasma, but there was an early vertical disruption. |
| Oct 7 1993 03:16:32:470PM | 931007022 | Joseph Snipes | Shot 22
Correcting some of the previous changes in EF2L gain and RXL X point controller gain. Reduced fill pressure to 1.1 x 10**-5 Torr. Dud! |
| Oct 7 1993 03:16:54:690PM | 931007023 | Joseph Snipes | Shot 23
Dud! |
| Oct 7 1993 03:23:41:850PM | 931007024 | Joseph Snipes | Shot 24
Lowering Bz by 1 mT to try to catch the oscillation in OH2 around Bz=0. Added -15 A to EF4. Good shot! |
| Oct 7 1993 03:38:07:320PM | 931007025 | Joseph Snipes | Shot 25
Returned to gas programming from shot 3 to return to low density and check the wall conditions. Gas programmed out to 0.6 s. Good shot! Hard x rays late. |
| Oct 7 1993 03:43:30:990PM | 931007025 | Joseph Snipes | Shot 25
Pellet at 1 s stopped runaway electrons. There is also RF at 1 s at low power. |
| Oct 7 1993 03:56:36:190PM | 931007026 | Joseph Snipes | Shot 26
Fizzle! |
| Oct 7 1993 04:13:11:790PM | 931007027 | Joseph Snipes | Shot 27
One more time . . . Decent shot but with runaways. |
| Oct 7 1993 04:28:52:320PM | 931007028 | Joseph Snipes | Shot 28
Go to higher density copying programming from shot 9. Pellet at 0.6 s. Turning off the gas programming at 0.58 s. Dud! |
| Oct 7 1993 04:52:28:360PM | 931007029 | Joseph Snipes | Shot 29
One more time . . . Good shot! Pellet at 0.6 s. |
| Oct 7 1993 05:02:45:560PM | 931007030 | Joseph Snipes | Shot 30
Somewhat more gas with no pellet. Dud! |
| Physics Operator Comments |
| Engineering Operator Comments | ||||
| Shot | Time | Type | Status | Comment |
| 1 | 08:43:54:100AM | Plasma | Ok | chopper control panel off --- no chopper this shot, all others no faults |
| 2 | 09:00:23:700AM | Plasma | Ok | no faults |
| 3 | 09:17:57:140AM | Plasma | Ok | no faults |
| 4 | 09:34:06:230AM | Plasma | Ok | no faults |
| 5 | 09:51:21:380AM | Plasma | Ok | no faults |
| 6 | 10:07:21:870AM | Plasma | Ok | no faults |
| 7 | 10:25:32:590AM | Plasma | Ok | no faults |
| 8 | 10:42:44:530AM | Plasma | Bad | engineering tree turned off for shot -- no supplies fired, no updates |
| 9 | 10:55:27:000AM | Plasma | Ok | no faults |
| 10 | 11:10:28:280AM | Plasma | Ok | no faults |
| 11 | 11:28:03:490AM | Plasma | Ok | no faults |
| 12 | 11:45:09:830AM | Plasma | Ok | no faults |
| 13 | 12:03:49:310PM | Plasma | Ok | no faults |
| 14 | 12:19:44:650PM | Plasma | Ok | no faults |
| 15 | 12:35:34:400PM | Plasma | Ok | no faults |
| 16 | 12:52:27:230PM | Plasma | Ok | no faults |
| 17 | 01:08:55:830PM | Plasma | Ok | no faults |
| 18 | 01:25:20:120PM | Plasma | Bad | oh2u >1 scr not conducting -- pf breaker pulled -- 1 bad fuse in EF1 |
| 19 | 01:53:50:240PM | Plasma | Ok | no faults |
| 20 | 02:07:42:170PM | Plasma | Ok | no faults |
| 21 | 02:22:52:000PM | Plasma | Ok | no faults |
| 22 | 02:46:51:740PM | Plasma | Ok | no faults |
| 23 | 03:01:01:410PM | Plasma | Ok | no faults |
| 24 | 03:17:57:280PM | Plasma | Ok | no faults |
| 25 | 03:34:36:140PM | Plasma | Ok | no faults |
| 26 | 03:51:16:950PM | Plasma | Ok | no faults |
| 27 | 04:07:14:470PM | Plasma | Ok | no faults |
| 28 | 04:25:22:810PM | Plasma | Ok | no faults |
| 29 | 04:41:22:460PM | Plasma | Ok | no faults |
| 30 | 04:57:25:920PM | Plasma | Ok | no faults |