| Miniproposals | ||||||||||
|
| Operators | |
| Session leader(s): | Unknown |
| Physics operator(s): | Joseph Snipes |
| Engineering operator(s): | Vinny Bertolino |
| Engineering Operator Run Comment |
| startup |
| Session Leader Plans |
| Physics Operators Plans |
| Session Leader Summaries |
| Physics Operator Summaries |
| Entered: Jul 7 2004 04:36:57:990PM |
| Author: To Be Determined |
| Plasma startup Engineer in charge: Vince Bertolino Physics Operator: Joseph Snipes Attempt to get plasmas after the long shutdown for the alternator repair. Start by using Ian's setup from shot 971029028 but with Br offset changed from 6.5 mT to 3 mT because the radial field was clearly wrong for that shot. Overall it was a successful run. Breakdowns were easily achieved on almost all shots. With a suggestion from Ian to raise Bz more quickly, the plasma took off on shot 15 with a nice 0.8 MA discharge lasting 1.6 sec. The next shot also went well until just after 1 sec when it disrupted due to a vertical instability. The machine can now be declared back in operation. We will boronize tomorrow and have physics runs in earnest on Monday. Shot 1: Relay test shot with no currents. Shot 2: Relay test shot with no currents. Shot 3: Relay test shot with no currents. O.K. Shot 4: Copied Phys_M_OUT waveform from Pulse Gas 3 shot 970625003 into the segment 2 Pulse Gas 3 voltage program to have pre-programmed gas valve programming rather than feedback control because the TCI is not working. Got breakdown. Ip up to 40 kA. Shot 5: Increased Br offset to 4 mT. Increased gas pre-puff by 5 msec to 25 msec duration. No breakdown. Br and Bz changed a lot! Shot 6: Try Br offset of 3.5 mT. No breakdown. Br looks O.K. Bz needs to come down by 5 mT or so. Shot 7: Reduced EF4 current from -1335 A to -1410 A to bring down Bz at breakdown. Got breakdown. Null looks better. Shot 8: Reduced pre-puff to 18 msec duration. Got breakdown. Shot 9: Reduced RCUR offset from 7000 to 5000. Got breakdown. Shot 10: Reduced EF4 by 25 A to -1435 A. Got breakdown. Shot 11: Reduced RCUR offset to 3000 and returned EF4 current to -1400 A. Got breakdown. Shot 12: Reduced EF4 again to -1417 A. Br seems to be drifting off. Reduced Br offset to 3 mT. Got breakdown. Shot 13: Returned RCUR offset to 7000 to see if increasing the dBz/dt is the right way to go as Ian suggests. Breakdown. No better. Shot 14: Raised OH1 voltage by 100 V between 7 and 15 msec. Raised OH2U and L voltages by 20 V at the same time. Got 45 kA. Not much better. Shot 15: Dropped OH1 voltage by 200 V between 7 and 15 msec. Dropped OH2U and L voltages by 20 V at the same time. Ian was right. Good plasma up to 800 kA and lasted 1.6 sec. Shot 16: Repeat. Good plasma. Vertically unstable around 1.05 sec. Disrupted at 0.8 MA. |
| Session Leader Comments |
| Physics Operator Comments | |||
| Oct 30 1997 05:06:35:020PM | Joseph Snipes | Overall it was a successful run. Breakdowns were easily achieved on almost all shots. With a suggestion from Ian to raise Bz more quickly, the plasma took off on shot 15 with a nice 0.8 MA discharge lasting 1.6 sec. The next shot also went well until just after 1 sec when it disrupted due to a vertical instability. The machine can now be declared back in operation. We will boronize tomorrow and have physics runs in earnest on Monday. | |
| Oct 30 1997 01:15:58:600PM | 971030001 | Joseph Snipes | Plasma startup Engineer in charge: Vince Bertolino Physics Operator: Joseph Snipes Attempt to get plasmas after the long shutdown for the alternator repair. Start by using Ian's setup from shot 971029028 but with Br offset changed from 6.5 mT to 3 mT because the radial field was clearly wrong for that shot. Shot 1: Relay test shot with no currents. O.K. |
| Oct 30 1997 01:49:29:690PM | 971030002 | Joseph Snipes | Shot 2: Relay test shot with no currents. |
| Oct 30 1997 01:49:41:140PM | 971030003 | Joseph Snipes | Shot 3: Relay test shot with no currents. O.K. |
| Oct 30 1997 02:12:04:810PM | 971030004 | Joseph Snipes | Shot 4: Copied Phys_M_OUT waveform from Pulse Gas 3 shot 970625003 into the segment 2 Pulse Gas 3 voltage program to have pre-programmed gas valve programming rather than feedback control because the TCI is not working. Got breakdown. Ip up to 40 kA. |
| Oct 30 1997 02:26:50:850PM | 971030005 | Joseph Snipes | Shot 5: Increased Br offset to 4 mT. Increased gas pre-puff by 5 msec to 25 msec duration. No breakdown. Br and Bz changed a lot! |
| Oct 30 1997 02:40:00:310PM | 971030006 | Joseph Snipes | Shot 6: Try Br offset of 3.5 mT. No breakdown. Br looks O.K. Bz needs to come down by 5 mT or so. |
| Oct 30 1997 03:04:50:390PM | 971030007 | Joseph Snipes | Shot 7: Reduced EF4 current from -1335 A to -1410 A to bring down Bz at breakdown. Got breakdown. Null looks better. |
| Oct 30 1997 03:19:25:910PM | 971030008 | Joseph Snipes | Shot 8: Reduced pre-puff to 18 msec duration. Got breakdown. |
| Oct 30 1997 03:31:36:370PM | 971030009 | Joseph Snipes | Shot 9: Reduced RCUR offset from 7000 to 5000. Got breakdown. |
| Oct 30 1997 03:42:18:370PM | 971030010 | Joseph Snipes | Shot 10: Reduced EF4 by 25 A to -1435 A. Got breakdown. |
| Oct 30 1997 03:53:20:670PM | 971030011 | Joseph Snipes | Shot 11: Reduced RCUR offset to 3000 and returned EF4 current to -1400 A. Got breakdown. |
| Oct 30 1997 04:12:54:830PM | 971030012 | Joseph Snipes | Shot 12: Reduced EF4 again to -1417 A. Br seems to be drifting off. Reduced Br offset to 3 mT. Got breakdown. |
| Oct 30 1997 04:32:42:780PM | 971030013 | Joseph Snipes | Shot 13: Returned RCUR offset to 7000 to see if increasing the dBz/dt is the right way to go as Ian suggests. Breakdown. No better. |
| Oct 30 1997 04:38:02:700PM | 971030014 | Joseph Snipes | Shot 14: Raised OH1 voltage by 100 V between 7 and 15 msec. Raised OH2U and L voltages by 20 V at the same time. Got 45 kA. Not much better. |
| Oct 30 1997 04:44:54:970PM | 971030015 | Joseph Snipes | Shot 15: Dropped OH1 voltage by 200 V between 7 and 15 msec. Dropped OH2U and L voltages by 20 V at the same time. Ian was right. Good plasma up to 800 kA and lasted 1.6 sec. |
| Oct 30 1997 05:05:46:200PM | 971030016 | Joseph Snipes | Shot 16: Repeat. Good plasma. Vertically unstable around 1.05 sec. Disrupted at 0.8 MA. |
| Engineering Operator Comments | ||||
| Shot | Time | Type | Status | Comment |
| 1 | 01:13:10:060PM | Test | Ok | |
| 2 | 01:25:23:350PM | Test | Ok | |
| 3 | 01:33:38:170PM | Test | Ok | |
| 4 | 02:01:03:820PM | Test | Ok | |
| 5 | 02:15:03:170PM | Plasma | Ok | |
| 6 | 02:29:05:410PM | Plasma | Ok | |
| 7 | 02:45:34:060PM | Plasma | Ok | |
| 8 | 03:05:25:960PM | Plasma | Ok | |
| 9 | 03:20:08:760PM | Plasma | Ok | |
| 10 | 03:30:56:170PM | Plasma | Ok | |
| 11 | 03:43:25:430PM | Plasma | Ok | |
| 12 | 04:03:19:220PM | Plasma | Ok | |
| 13 | 04:13:14:670PM | Plasma | Ok | |
| 14 | 04:25:07:080PM | Plasma | Ok | |
| 15 | 04:40:33:340PM | Plasma | Ok | |
| 16 | 04:56:09:360PM | Plasma | Ok | |