| Miniproposals | ||||||||||
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| Operators | |
| Session leader(s): | Unknown |
| Physics operator(s): | Robert Granetz |
| Engineering operator(s): | Bill Byford,Ed Fitzgerald,Gary Dekow |
| Engineering Operator Run Comment |
| Continue Startup and begin using A-coils for locked mode studies |
| Session Leader Plans |
| Physics Operators Plans |
| Session Leader Summaries |
| Physics Operator Summaries |
| Entered: Jul 7 2004 04:37:17:567PM |
| Author: To Be Determined |
| Physics operator summary for run 1030425 (Friday): Startup continuation and initial A-coil locked mode studies Physics operator: R. Granetz Engineers in charge: G. Dekow/W. Byford/E. Fitzgerald Summary: No physics results were obtained from this first A-coil run. We started the day at 0.8 MA and very low density. This gave reproducible locked modes for the first few plasmas (shots 01, 05). Then we switched on the A-coils for a series of shots (06, 07, 08), and observed that the locked mode went away. However, the density was also creeping up during this time, and since the gas valves were off for most of the shot, it wasn't easy to get the density to stay very low as the day progressed. We then turned off the A-coil (shots 09, 10) and still did not see a locked mode, presumably because of the slightly increased density. So this was an inconclusive result. I then went to 1 MA in order to get a more robust locked mode (shot 11). This worked, but we also got a disruption during rampdown, which precipitated a series of fizzles. Things got substantially worse when the data acquisition cycle began to hang for many shots in the afternoon. I managed to get only 2 more plasmas, and both of these disrupted early due to large molybdenum injections. On shot 25, the A-coil TMX should have given current, but didn't. This supply will have to be checked out on Monday. Scorecard: 11 plasmas 6 fizzles 0 duds 7 test or no-power shot cycle 2 aborted and/or screwed up by computer problems ---------- 26 total ------------------------------------------------------------------------------- Engineering setup for Friday, 25 April 2003 Purpose: continue startup, and begin using A-coils for locked mode studies Physics operator: R. Granetz ECDC overnight in D2 at 2e-4 Torr, stopping by 07:00. Bake at 60 C overnight as well, if possible. Run begins at 09:00 and ends at 17:00. Power systems the same as on 1030424007 (0.8 MA, 5.4 T, lower single null) A-coil hookup: +Dtop -Dbot -Jtop +Jbot Gas setup: fill B-Top with 6 psi D2 Hybrid enabled (PG4) fill B-side lower with 1 psi Ar Hybrid enabled (PG1) fill B-side upper with 10 psi D2 Hybrid DISABLED (PG2) (for ECDC) fill C-side with 30 psi D2 Hybrid enabled (PG3) Enable the following gate valves, assuming no vacuum problems: ECE ------------------------------------------------------------------------------- RF Setup: All 4 transmitters Run On by 08:30. ------------------------------------------------------------------------------- Run Plan: Start with shot 7 from yesterday (1030424007), which had a clear locked mode, yet had PCS density feedback enabled. Assuming the locked mode signatures are seen, then begin using the new A-coil set to see if they have any effect on these signatures. I will probably stick to full current (2.3 kA), with quad sets of coils energized (upper and lower at opposite toroidal locations. ------------------------------------------------------------------------------- ECDC was done overnight, as well as a 60 C bake. Hybrid coldstart done by the engineering group; no errors found Loaded PCS from shot 1030424007 (0.8 MA, 5.4 T, single null lower), and programmed in a 40 ms argon pulse starting at t=0.35 s. ------------------------------------------------------------------------------- Shot 01 -- Plasma. Ramped all the way down. 0.8 MA, 5.4 T, nl_04=0.5e20 m-2. Plenty of hard x-rays. Large locked mode starts at t=1.31 s. Startup had a bounce. Bz0 was a bit high, but I'll leave it for now. Next shot: repeat with no changes. I want to get some idea of the variability of the onset time of the locked mode. Shot 02 -- No-power shot cycle - one of the engineering decoders failed to init properly. Shot 03 -- Plasma. Good shot. There was no locked mode on this shot, possibly because the RF turned on (1.5 MW) and raised the density a bit (and heated a little as well). This sensitivity to plasma parameters may make the A-coil studies difficult to interpret. Next shot: one more repeat, this time without RF. Shot 04 -- No-power shot cycle - one of the engineering decoders failed to init properly (again). Shot 05 -- Plasma. Good shot. Got the locked mode back. It starts at about t=1.33 s (about 50 ms different than on shot 01). There were NO hard x-rays on this shot, and no bounce during the startup. Next shot: energize the A-coils. I'll have them go from 1.0 s to 1.6 s. The initial hookup maximizes m=2/n=1. Shot 06 -- Plasma. Good shot. The locked mode is gone! We need to see if this is reproducible, or just a fluke. (At t=1.35 s, there was a particularly large sawtooth on the GPC ECE.) Hard x-rays are back, and so is the startup bounce. Note: a small helium puff was on at t=1.3 s for the first time today. I will have them move it to t=0.7 s for following shots. A-coil details: +Dtop -Dbot -Jtop +Jbot (maximize m=2/n=1), Programmed for 3700 amps (including offset), PLC limit=4 kA, Ramp on: t=1.0-1.1 s, Ramp off: t=1.6-1.7 s. Actual measured current: 2000 A. Next shot: repeat with no changes, including the A-coils. We need to check whether there's really an effect here or not. Shot 07 -- Plasma. Good shot. No locked mode. 2 for 2. Hard x-rays and the startup bounce are still with us. The density has been creeping up from shot-to-shot, even though NL_04 feedback is on. Martin points out that the EFIT Wp does not droop very much during the discharge for shots 06 and 07 compared to shots 01 and 05. Next shot: one more repeat with no changes. A-coils will still be on. Shot 08 -- Plasma. Good shot. No locked mode. 3 for 3, but the density has been creeping up, so it may not mean anything. This startup had two bounces, just to make sure that there were plenty of hard x-rays. Next shot: turn off the A-coils. Will the locked mode come back? Shot 09 -- Plasma. Good shot. No locked mode. So it seems that the density increases over the last several shots have been responsible for getting rid of the locked mode, rather than the A-coils. Note: A-coils have been disabled at the PLC. The programmed waveform has been left on the PCS wire. Next shot: reduce nl_04 during the first part of the shot. (It's already asking for negative density after t=0.8 s.) Shot 10 -- Plasma. Good shot. Still no locked mode, even though the density is a little lower. But I don't think we'll be able to get the density much lower, so maybe I'll try raising the plasma current. Next shot: raise Ip to 1.0 MA, keeping the density low. Shot 11 -- Plasma. Disrupted at t=1.6 s. Big locked mode, with onset at t=0.92 s. (Also lots of hard x-rays.) Next shot: re-enable the A-coils. Also increase pre-fill pressure a bit. Shot 12 -- Fizzle. Lots of carbon...chalk it up to the disruption, rather than to the higher pre-fill pressure. No bounce. Next shot: try again, no changes. A-coils will be energized. Shot 13 -- Fizzle. Several bounces, really ugly. Next shot: reduce pre-fill a touch. Keep the A-coils on. Shot 14 -- Plasma. Disrupted at t=0.76 s. Looks like an injection killed this one early. Hard x-rays were reduced, but not eliminated. Next shot: try again, no changes. Keep the A-coils on. Shot 15 -- Fizzle. Next shot: add -10 amps to IC_EF4U, subtract 0.5 mT from Br0 offset. Leave A-coils energized. Shot 16 -- No-power shot cycle. Problem with engineering camac init. Shot 17 -- Fizzle. Lots of carbon light. Breakdown was nice and early though. Next shot: add -5 A to IC_EF4U. Keep A-coils energized. Shot 18 -- Fizzle. Next shot: add 0.5 mT to Br0. Keep A-coils energized. Shot 19 -- Fizzle. Next shot: reload shot 11, except reduce Ip to 0.9 MA. Keep A-coils energized. Shot 20 -- No-power shot cycle. Data system hung. Shot 21 -- Aborted. Shot 22 -- No-power shot cycle. Data system hung. Shot 23 -- No-power shot cycle. Data system hung. Shot 24 -- No-power shot cycle. Data system hung. Shot 25 -- Plasma. Disrupted at t=0.71 s. Brick. The A-coil TMX supply doesn't seem to have worked. EngOp is looking into it. Next shot: reduce pre-fill puff by 5 ms for disruption recovery. A-coils are still being energized. Shot 26 -- Aborted. End of run. |
| Session Leader Comments |
| Physics Operator Comments | |||
| Apr 25 2003 08:29:30:353AM | Robert Granetz | Engineering setup for Friday, 25 April 2003 Purpose: continue startup, and begin using A-coils for locked mode studies Physics operator: R. Granetz ECDC overnight in D2 at 2e-4 Torr, stopping by 07:00. Bake at 60 C overnight as well, if possible. Run begins at 09:00 and ends at 17:00. Power systems the same as on 1030424007 (0.8 MA, 5.4 T, lower single null) A-coil hookup: +Dtop -Dbot -Jtop +Jbot Gas setup: fill B-Top with 6 psi D2 Hybrid enabled (PG4) fill B-side lower with 1 psi Ar Hybrid enabled (PG1) fill B-side upper with 10 psi D2 Hybrid DISABLED (PG2) (for ECDC) fill C-side with 30 psi D2 Hybrid enabled (PG3) Enable the following gate valves, assuming no vacuum problems: ECE ------------------------------------------------------------------------------- RF Setup: All 4 transmitters Run On by 08:30. ------------------------------------------------------------------------------- Run Plan: Start with shot 7 from yesterday (1030424007), which had a clear locked mode, yet had PCS density feedback enabled. Assuming the locked mode signatures are seen, then begin using the new A-coil set to see if they have any effect on these signatures. I will probably stick to full current (2.3 kA), with quad sets of coils energized (upper and lower at opposite toroidal locations. | |
| Apr 25 2003 05:20:58:023PM | Robert Granetz | ECDC was done overnight, as well as a 60 C bake. Hybrid coldstart done by the engineering group; no errors found Loaded PCS from shot 1030424007 (0.8 MA, 5.4 T, single null lower), and programmed in a 40 ms argon pulse starting at t=0.35 s. | |
| Apr 25 2003 09:09:40:523AM | 1030425001 | Robert Granetz | Shot 01 -- Plasma. Ramped all the way down. 0.8 MA, 5.4 T, nl_04=0.5e20 m-2. Plenty of hard x-rays. Large locked mode starts at t=1.31 s. Startup had a bounce. Bz0 was a bit high, but I'll leave it for now. Next shot: repeat with no changes. I want to get some idea of the variability of the onset time of the locked mode. |
| Apr 25 2003 09:13:05:130AM | 1030425002 | Robert Granetz | Shot 02 -- Test. No-power shot cycle - one of the engineering decoders failed to init properly. |
| Apr 25 2003 09:33:42:687AM | 1030425003 | Robert Granetz | Shot 03 -- Plasma. Good shot. There was no locked mode on this shot, possibly because the RF turned on (1.5 MW) and raised the density a bit (and heated a little as well). This sensitivity to plasma parameters may make the A-coil studies difficult to interpret. Next shot: one more repeat, this time without RF. |
| Apr 25 2003 09:41:56:870AM | 1030425004 | Robert Granetz | Shot 04 -- No-power shot cycle - one of the engineering decoders failed to init properly (again). |
| Apr 25 2003 10:05:39:920AM | 1030425005 | Robert Granetz | Shot 05 -- Plasma. Good shot. Got the locked mode back. It starts at about t=1.33 s (about 50 ms different than on shot 01). There were NO hard x-rays on this shot, and no bounce during the startup. Next shot: energize the A-coils. I'll have them go from 1.0 s to 1.6 s. The initial hookup maximizes m=2/n=1. |
| Apr 25 2003 10:36:05:793AM | 1030425006 | Robert Granetz | Shot 06 -- Plasma. Good shot. The locked mode is gone! We need to see if this is reproducible, or just a fluke. (At t=1.35 s, there was a particularly large sawtooth on the GPC ECE.) Hard x-rays are back, and so is the startup bounce. Note: a small helium puff was on at t=1.3 s for the first time today. I will have them move it to t=0.7 s for following shots. A-coil details: +Dtop -Dbot -Jtop +Jbot (maximize m=2/n=1), Programmed for 3700 amps (including offset), PLC limit=4 kA, Ramp on: t=1.0-1.1 s, Ramp off: t=1.6-1.7 s. Actual measured current: 2000 A. Next shot: repeat with no changes, including the A-coils. We need to check whether there's really an effect here or not. |
| Apr 25 2003 10:53:49:490AM | 1030425007 | Robert Granetz | Shot 07 -- Plasma. Good shot. No locked mode. 2 for 2. Hard x-rays and the startup bounce are still with us. The density has been creeping up from shot-to-shot, even though NL_04 feedback is on. Martin points out that the EFIT Wp does not droop very much during the discharge for shots 06 and 07 compared to shots 01 and 05. Next shot: one more repeat with no changes. A-coils will still be on. |
| Apr 25 2003 11:04:59:587AM | 1030425008 | Robert Granetz | Shot 08 -- Plasma. Good shot. No locked mode. 3 for 3, but the density has been creeping up, so it may not mean anything. This startup had two bounces, just to make sure that there were plenty of hard x-rays. Next shot: turn off the A-coils. Will the locked mode come back? |
| Apr 25 2003 11:27:37:357AM | 1030425009 | Robert Granetz | Shot 09 -- Plasma. Good shot. No locked mode. So it seems that the density increases over the last several shots have been responsible for getting rid of the locked mode, rather than the A-coils. Note: A-coils have been disabled at the PLC. The programmed waveform has been left on the PCS wire. Next shot: reduce nl_04 during the first part of the shot. (It's already asking for negative density after t=0.8 s.) |
| Apr 25 2003 11:44:17:007AM | 1030425010 | Robert Granetz | Shot 10 -- Plasma. Good shot. Still no locked mode, even though the density is a little lower. But I don't think we'll be able to get the density much lower, so maybe I'll try raising the plasma current. Next shot: raise Ip to 1.0 MA, keeping the density low. |
| Apr 25 2003 12:11:46:627PM | 1030425011 | Robert Granetz | Shot 11 -- Plasma. Disrupted at t=1.6 s. Big locked mode, with onset at t=0.92 s. (Also lots of hard x-rays.) Next shot: re-enable the A-coils. Also increase pre-fill pressure a bit. |
| Apr 25 2003 12:29:28:793PM | 1030425012 | Robert Granetz | Shot 12 -- Fizzle. Lots of carbon...chalk it up to the disruption, rather than to the higher pre-fill pressure. No bounce. Next shot: try again, no changes. A-coils will be energized. |
| Apr 25 2003 12:35:54:053PM | 1030425013 | Robert Granetz | Shot 13 -- Fizzle. Several bounces, really ugly. Next shot: reduce pre-fill a touch. Keep the A-coils on. |
| Apr 25 2003 12:59:04:323PM | 1030425014 | Robert Granetz | Shot 14 -- Plasma. Disrupted at t=0.76 s. Looks like an injection killed this one early. Hard x-rays were reduced, but not eliminated. Next shot: try again, no changes. Keep the A-coils on. |
| Apr 25 2003 01:11:13:733PM | 1030425015 | Robert Granetz | Shot 15 -- Fizzle. Next shot: add -10 amps to IC_EF4U, subtract 0.5 mT from Br0 offset. Leave A-coils energized. |
| Apr 25 2003 01:16:46:257PM | 1030425016 | Robert Granetz | Shot 16 -- No-power shot cycle. Problem with engineering camac init. |
| Apr 25 2003 01:52:33:750PM | 1030425017 | Robert Granetz | Shot 17 -- Fizzle. Lots of carbon light. Breakdown was nice and early though. Next shot: add -5 A to IC_EF4U. Keep A-coils energized. |
| Apr 25 2003 02:26:29:440PM | 1030425018 | Robert Granetz | Shot 18 -- Fizzle. Next shot: add 0.5 mT to Br0. Keep A-coils energized. |
| Apr 25 2003 02:56:52:660PM | 1030425020 | Robert Granetz | Shot 19 -- Fizzle. Next shot: reload shot 11, except reduce Ip to 0.9 MA. Keep A-coils energized. |
| Apr 25 2003 03:19:03:600PM | 1030425020 | Robert Granetz | Shot 20 -- No-power shot cycle. Data system hung. |
| Apr 25 2003 03:41:09:400PM | 1030425021 | Robert Granetz | Shot 21 -- Aborted. |
| Apr 25 2003 03:40:35:243PM | 1030425022 | Robert Granetz | Shot 22 -- No-power shot cycle. Data system hung. |
| Apr 25 2003 03:58:06:520PM | 1030425023 | Robert Granetz | Shot 23 -- No-power shot cycle. Data system hung. |
| Apr 25 2003 04:20:59:087PM | 1030425024 | Robert Granetz | Shot 24 -- No-power shot cycle. Data system hung. |
| Apr 25 2003 04:45:32:267PM | 1030425025 | Robert Granetz | Shot 25 -- Plasma. Disrupted at t=0.71 s. Brick. The A-coil TMX supply doesn't seem to have worked. EngOp is looking into it. Next shot: reduce pre-fill puff by 5 ms for disruption recovery. A-coils are still being energized. |
| Apr 25 2003 05:00:16:070PM | 1030425025 | Robert Granetz | Shot 26 -- No-power shot cycle. Data system hung. |
| Engineering Operator Comments | ||||
| Shot | Time | Type | Status | Comment |
| 1 | 08:54:42:237AM | Plasma | Ok | |
| 2 | 09:08:51:240AM | Plasma | Bad | EF4 Decoder did not init properly |
| 3 | 09:20:18:263AM | Plasma | Ok | |
| 4 | 09:38:40:717AM | Plasma | Bad | BUSLV Ddecoder Init Fail |
| 5 | 09:52:47:960AM | Plasma | Ok | |
| 6 | 10:21:16:817AM | Plasma | Ok | |
| 7 | 10:37:50:687AM | Plasma | Ok | |
| 8 | 10:54:01:303AM | Plasma | Ok | |
| 9 | 11:10:35:987AM | Plasma | Ok | |
| 10 | 11:27:55:950AM | Plasma | Ok | |
| 11 | 11:56:26:197AM | Plasma | Ok | |
| 12 | 12:15:41:240PM | Plasma | Ok | |
| 13 | 12:30:06:530PM | Plasma | Ok | |
| 14 | 12:43:58:893PM | Plasma | Ok | |
| 15 | 01:00:28:980PM | Plasma | Ok | |
| 16 | 01:13:59:250PM | Plasma | Bad | Engineering Power System Camac Fault |
| 17 | 01:40:55:200PM | Plasma | Ok | |
| 18 | 02:13:45:877PM | Plasma | Ok | |
| 20 | 02:48:00:007PM | Plasma | Ok | |
| 21 | 03:06:18:673PM | Test | Bad | |
| 22 | 03:36:42:877PM | Test | Ok | Cycle Test for IGOR |
| 23 | 03:55:28:923PM | Test | Ok | Cycle Test for IGOR |
| 24 | 04:17:42:893PM | Test | Ok | Cycle Test for IGOR |
| 25 | 04:29:20:723PM | Plasma | Ok | |
| 27 | 10:34:43:827AM | Test | Bad | |
| 29 | 02:11:10:673PM | Test | Bad | |
| 30 | 02:22:11:433PM | Test | Bad | |
| 31 | 02:37:19:587PM | Test | Bad | |
| 32 | 02:46:07:110PM | Test | Bad | |
| 33 | 03:05:06:607PM | Test | Bad | |
| 34 | 03:20:53:243PM | Test | Bad | |
| 35 | 03:39:49:117PM | Test | Bad | |
| 36 | 03:59:57:210PM | Test | Bad | |
| 37 | 04:10:41:517PM | Test | Bad | |
| 38 | 04:24:44:700PM | Test | Bad | |
| 39 | 04:42:17:230PM | Test | Bad | |