| Miniproposals | ||||||||||
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| Operators | |
| Session leader(s): | Robert Granetz |
| Physics operator(s): | Steve Wolfe |
| Engineering operator(s): | Vinny Bertolino,Frank Silva |
| Engineering Operator Run Comment |
| Restart Operation |
| Session Leader Plans |
| Physics Operators Plans |
| Session Leader Summaries |
| Physics Operator Summaries |
| Entered: Jul 7 2004 04:36:56:787PM |
| Author: To Be Determined |
| Physop summary for 970514 MP#170A SL Granetz PO Wolfe EO Silva, Bertolino Plan: ----- This run will attempt to get the first C-Mod tokamak plasmas of 1997. If we are successful in getting startup and current rise we will run cleanup discharges at up to 0.8MA, with the shot length up to 1.2 sec (EOF). We will start with integrated power system tests to verify OH and EF1 operation up to nominal high pre-charge values, then proceed to develop the null to obtain breakdown and hopefully current rise. Specifically: 1) "Tuesday test": OH's only at 10kA, PLC control to check coax resistance 2) Engineering setup as on 960805015 (Low pre-charge case). TF on PLC control. K-side to 20psi D2; B-top to 5psi D2- Enable both for hybrid.(why not?) PCS copied from same shot. Just verify supplies all working together and push on to higher pre-charge. 3) Engineering setup as on 960828005 (High pre-charge case). TF under PLC control. K-side 20psi D2; B-top 5psi D2 (unchanged from above). Hybrid enable. PCS copied from same shot, maybe adjust pre-puff to higher pressure. 4) Tweak up null to get a breakdown. 5) Tweak up current rise, using the usual black magic. 6) If it seems reasonable, back off the current to try to extend the pulse length. 7) If we get full length pulses at lower current (say 600kA) then raise to 800kA for remainder of run. Results: ------- We got to somewhere between step 5 and 6. Two current rises were obtained, on shots 8 and 26; shot 26 got to 600ka at 200msec. We also had numerous fizzles. Both plasmas were extremely dirty and resistive. ECE measured temperatures around 300eV. The OH test on shot 1 indicated that we had a problem with the OH1 rogowski; we also had CAMAC problems on the BUSLV signals on this shot. After lots of testing and two more PLC test shots, it was found that the problem was related to a loose connector housing. Shot 3 gave signal on all 3 OH rogowskis. Coax resistances were fine on the tests. Shot 4 was a low-precharge programing from #960805015. Everything worked except the chopper. Gas pulse fired as programmed; this was the first hybrid gas puff we've done this year. Shot 5 was set up with high precharge from 960828005. Everything worked, except no flash. Shot 6 was a Br tweak, which didn't get a breakdown. Shot 7 was a gas tweak, to higher pressure, and got a breakdown; first flash of the year. Shot 8 was a repeat, and got a good current rise to over 400kA. Shots 9 - 25 consisted of lots of fiddling, with some duds and some fizzles. See the logbook (Physics_Operator topic) for details. Shot 26 got another plasma, this one reaching 600kA at 200msec. The change leading (?) to this plasma was an increase in the pre-puff to 26msec. It seemed to like the higher pressure. Shots 27 and 28 were basically recovery shots from the big gas load stirred up by 26. Both fizzled. Shot 29 was supposed to be an EF1L-only test shot to diagnose an oscillation that appeared at shot 17 (see below). Unfortunately, we ended up blowing fuses and incurred a long delay. Shots 30-35 were plasma attempts, only one of which (33) even got a fizzle. These were also plagued by CAMAC errors on magnetics signals (and others). 35 was the last real shot (a dud). JAS took two CAMAC-only test shots after 17:00 to try to track down the highway problem, but these did not experience any difficulties. Problems: -------- Power supplies worked well, except for a chopper problem on shot 4 (blown fuses again), and the EF1L problem that appeared on shot 17 and continued for the rest of the run. This was the same problem that appeared earlier in the week and then vanished, a larger than normal ripple on the voltage which produced about a 100A ripple on the current. After the run the engineers found a fault on the cosine board and replaced it. In addition to blowing fuses, the test shot 29 produced collateral damage in that the bus diagnostics on EF1L got zapped during the repair and testing (hipot). The null was somewhat variable for constant supply programming. It may be useful to put higher gain, or integral gain, on some supplies, or to put Bz feedback on. We had several CAMAC highway problems throughout the day, including LPE's and MEDOFL's, particularly on shot 1 and shots 30-35. On a couple of shots Jim Irby noted possible fluorocarbon bursts. It is not clear if these are causing any problems, and we still don't know where they are coming from. shot 27 had a visible flash on the TV, but no signal on the standard visible light detectors. This may have been a weird CAMAC problem? Comments: --------- I did some tweaking of the RCUR offset in segment 1, but ended up back at the original setting (7000). Changing this the first time required recalling the predictor algorithm to incorporate the switched BP12 coil, and this seemed to make some difference in the output. No other predictors were updated. This should probably be done. We clearly need a lot more cleanup, based on the two plasmas we got today. It looks like the breakdown and even current rise favor high pre-puffs. Cooling worked well all day. We had no apparent vacuum problems except the known small leak and the fluorocarbon bursts. Offsets are remarkably similar to last year. Scorecard -------- tests 5 duds 16 fizzles 12 plasmas 2 ------ -- total 35 |
| Session Leader Comments |
| Physics Operator Comments | |||
| May 14 1997 07:09:24:320AM | Steve Wolfe | Run Plan for Wed. 970514 MP#170A Restart Operation: May 1997 SL: Granetz PO: wolfe EO: Bertolino,Silva This run will attempt to get the first C-Mod tokamak plasmas of 1997. If we are successful in getting startup and current rise we will run cleanup discharges at up to 0.8MA, with the shot length up to 1.2 sec (EOF). | |
| May 14 1997 07:09:54:350AM | Steve Wolfe | We will start with integrated power system tests to verify OH and EF1 operation up to nominal high pre-charge values, then proceed to develop the null to obtain breakdown and hopefully current rise. Specifically: 1) "Tuesday test": OH's only at 10kA, PLC control to check coax resistance 2) Engineering setup as on 960805015 (Low pre-charge case). TF on PLC control. K-side to 20psi D2; B-top to 5psi D2- Enable both for hybrid.(why not?) PCS copied from same shot. Just verify supplies all working together and push on to higher pre-charge. 3) Engineering setup as on 960828005 (High pre-charge case). TF under PLC control. K-side 20psi D2; B-top 5psi D2 (unchanged from above). Hybrid enable. PCS copied from same shot, maybe adjust pre-puff to higher pressure. 4) Tweak up null to get a breakdown. 5) Tweak up current rise, using the usual black magic. 6) If it seems reasonable, back off the current to try to extend the pulse length. 7) If we get full length pulses at lower current (say 600kA) then raise to 800kA for remainder of run. | |
| May 14 1997 07:27:43:180AM | Steve Wolfe | Irby reports that t here was fluorocarbon generation last night when the ECDC ran down to low pressure. 07:15 Do a coldstart = Looks ok. PCS load from 960805015 - note that it took me three tries to get it typed right, and PCS bombed out to the IDL prompt on each error; this seems to be a bug in PCS- should fail to load gracefully. Note that this shot has a 17msec pre-puff; should be fine (we're only using this as an integration test anyway. I got the acknowledge widget on the change to BP12 made last night. Don't bother recalculating predictors for this test. We'll see when we get to the final setting Load at 14-May-1997 07:27:12.00 | |
| May 14 1997 08:34:30:830AM | 970514001 | Steve Wolfe | Shot 1 : "Tuesday" OH test Irby found last night that there was a baseline drift problem with the TF rogowski. As of now, it is still not fixed; use the BTOR value. No bus rogowski traces. Jim says coax resistances look ok, assumng it's 10kA. CAMAC store error on BUSLV. Hybrid inputs show signal on OH2's, but not OH1. Also, live scope did not show OH1. So we have two problems - Jim is doing CAMAC test; we need to check out the Rog. separately. |
| May 14 1997 09:05:53:940AM | 970514001 | Steve Wolfe | Shot 1: Note that Tom "restored" data from BUSLV CAMAC after Irby had taken a test shot, so the rogowski signals in the tree on shot 1 show a sine wave on OH1. |
| May 14 1997 09:18:06:990AM | 970514001 | Steve Wolfe | Shot 1 : Rogowski checks out ok. Sine wave signal from sig. gen. shows up on BUSLV and on Hybrid test shots (hybrid test shot is 272). Rogowski resistance is 9.7 ohms. Hook it back up and try again test again. |
| May 14 1997 09:04:29:960AM | 970514002 | Steve Wolfe | Shot 2: Try OH PLC test again. Got the BUSLV camac, still no OH1 rog signal on anything. |
| May 14 1997 09:24:38:640AM | 970514003 | Steve Wolfe | Shot 3: Can't find anything wrong with Rogowski, except housing on connector was loose? Try another OH PLC test shot. This time we have signal from all OH rogowskis. I guess tightening the housing fixed it. On with the program, till the next SNAFU. |
| May 14 1997 10:02:46:540AM | 970514004 | Steve Wolfe | Shot 4: Setup as for 960805015, go for everything. Note that we are not getting TORVAC.GAS.PVALVE_*:Waveform signals. DOn't know why. No Chopper, got everything else. No flash (Big Surprise!) GOt gas - f.d. doesn't seem to shut it down until .2 sec. Still no signals from PVALVE, but J. Goetz recovered the raw data. |
| May 14 1997 10:22:00:030AM | 970514005 | Steve Wolfe | Shot 5: On to step 3. LOad from 960828005 For now don't bother with updating the predictors. Load at 14-May-1997 10:11:29.00 They found some blown fuses in the chopper again. No flash. Got all supplies. Null doesn't look terrible. A little negative on BR, maybe a little low on Bz. |
| May 14 1997 10:42:42:070AM | 970514006 | Steve Wolfe | Shot 6: Change Br offset from .0065 to .007 Change pre-puff from 16 msec to 20msec. No flash. Got more Bz this time, looks like EF4 current is 15A lower. |
| May 14 1997 10:52:14:350AM | 970514007 | Steve Wolfe | Shot 7: Raise pre-puff to 22msec. No change to fields, see how reproducible they are. Got a flash. 30kA weak fizzle. Field null is changed again. breakdown at 7msec. |
| May 14 1997 11:05:45:180AM | 970514008 | Steve Wolfe | Shot 8: repeat flash - 400kA then disrupts at 140msec. Dirty resistive but not bad for the first current rise. |
| May 14 1997 11:20:13:810AM | 970514009 | Steve Wolfe | Shot 9:repeat Dud. Null looks acceptable; just junk I guess. |
| May 14 1997 11:27:04:870AM | 970514010 | Steve Wolfe | Shot 10: repeat fizzle. Late breakdown 13msec. Null a little different again. |
| May 14 1997 11:35:31:420AM | 970514011 | Steve Wolfe | shot 11: repeat dud. null looks ok. Try again. |
| May 14 1997 11:45:18:780AM | 970514012 | Steve Wolfe | shot 12 repeat dud. |
| May 14 1997 12:03:33:100PM | 970514013 | Steve Wolfe | shot 13: raise Br to .0075 (up by .5mT) fizzle. Late breakdown (13msec) but got a little current (45kA). Looks like I went the wrong way on the Br tweak, as far as the flux plots are concerned. |
| May 14 1997 12:10:42:290PM | 970514014 | Steve Wolfe | shot 14: lower Br to .0065 (down by 1mT) dud - radial field looks ok, but now we have different vertical field. |
| May 14 1997 12:22:53:870PM | 970514015 | Steve Wolfe | shot 15: repeat fizzle 6.5msec bd. seems to be moving inside. |
| May 14 1997 12:37:44:500PM | 970514016 | Steve Wolfe | shot 16: repeat fizzle - late breakdown (15msec) and it bounced once moving out. |
| May 14 1997 12:49:26:790PM | 970514017 | Steve Wolfe | shot 17: change rcur offset from 7000 to 6000. in seg. 1 Make predictor failed because of new BP loop. Call the alg. then put in 6000. for the offset. dud. RCUR went the way I expected, but maybe not the way the plasma wanted. Null looks pretty bad. Try again before reverting. |
| May 14 1997 12:56:56:890PM | 970514018 | Steve Wolfe | shot 18: repeat dud. ok,untweak the rcur offset. |
| May 14 1997 01:11:25:990PM | 970514019 | Steve Wolfe | shot 19: Set RCUR offset in Seg 1 back to 7000 (from 6000). Note that this leaves the new predictor in place on Seg1 RCUR. Vinnie reports that EF1L is back to having a lot of voltage hash on shot 18. Actually it was bad on 17 as well, though not as bad. fizzle. bd at 7msec, no current rise. Rcur now thinks it's outside by 2000 a-m. EF1L is still doing it's thing. |
| May 14 1997 01:22:23:320PM | 970514020 | Steve Wolfe | shot 20: Change RCUR offset to 8000 (from 7000) in seg 1 fizzle. weak late bd (13msec). RCUR still outside, a little further? |
| May 14 1997 01:32:03:500PM | 970514021 | Steve Wolfe | shot 21: Change RCUR offset to 5000 (from 8000) in seg 1 dud. RCUR starts at 1000, compared to >2000. Bz is less positive after 10msec. |
| May 14 1997 01:46:32:020PM | 970514022 | Steve Wolfe | shot 22: Change RCUR offset to 7000 (from 5000) in seg 1 Vinnie is going to take out the reverse bridge on EF1L for this shot to try to diagnose the big oscillations. We are seeing 100A ripple on the EF1L current. late fizzle (15msec) and it moves in. 30kA current. EF1L still bad oscillation. |
| May 14 1997 01:57:48:340PM | 970514023 | Steve Wolfe | shot 23: Lower the pre-puff from 22msec to 18msec Reverse bridge still out on EF1L, but added instrumentation. fizzle. 11msec bd. current to 30kA, moves in. |
| May 14 1997 02:08:26:130PM | 970514024 | Steve Wolfe | shot 24: repeat dud. |
| May 14 1997 02:14:35:700PM | 970514025 | Steve Wolfe | shot 25: lower pre-puff to 16msec (RSG made me do it). dud. |
| May 14 1997 02:27:24:350PM | 970514026 | Steve Wolfe | shot 26: raise pre-puff to 26msec plasma - 200msec gets to 600kA. |
| May 14 1997 02:41:11:010PM | 970514027 | Steve Wolfe | shot 27: reduce Ip program to 600ka. fizzle? Saw a flash on the TV, but no signal on halpha or z-meter. |
| May 14 1997 02:48:25:910PM | 970514028 | Steve Wolfe | shot 28: repeat fizzle. 6.8msec, no current. |
| May 14 1997 03:04:50:180PM | 970514029 | Steve Wolfe | shot 29: EF1L PLC shot only Vinnie is taking out half the EF1L (running as a 6-pulser) to isolate the bad whatever. Test didn't work. Put things back. |
| May 14 1997 04:07:09:140PM | 970514030 | Steve Wolfe | shot 30: repeat of 28. (except the whole EF1L supply will be back in, after replacing some fuses blown on the test shot 29.) dud lots of CAMAC errors on magnetics. Can't diagnose the null directly, but it looks like EF4 is at 1420A, which is more than we had been getting. Try again. |
| May 14 1997 04:35:30:040PM | 970514031 | Steve Wolfe | shot 31: repeat of 28. another dud? Still getting CAMAC errors on magnetics! |
| May 14 1997 04:43:07:410PM | 970514032 | Steve Wolfe | shot 32: try again. TWF claims to have fixed the camac another dud. This time mflux gets data, although there is one mds error reading BP18_jk?? May be a radial field problem, but it doesn't look that bad. |
| May 14 1997 04:48:51:830PM | 970514033 | Steve Wolfe | shot 33: drop pre-puff to 22msec fizzle, bd at 5msec. More camac errors on magnetics |
| May 14 1997 04:57:13:850PM | 970514034 | Steve Wolfe | shot 34: drop pre-puff to 20msec dud |
| May 14 1997 05:03:20:480PM | 970514035 | Steve Wolfe | shot 35: rise pre-puff to 24msec dud |
| Engineering Operator Comments | ||||
| Shot | Time | Type | Status | Comment |
| 1 | 08:23:23:020AM | Test | Ok | |
| 2 | 08:59:21:360AM | Test | Ok | |
| 3 | 09:21:32:890AM | Test | Ok | |
| 4 | 09:50:20:060AM | Plasma | Ok | |
| 5 | 10:15:37:290AM | Plasma | Ok | |
| 6 | 10:29:30:510AM | Plasma | Ok | |
| 7 | 10:46:24:790AM | Plasma | Ok | |
| 8 | 10:56:52:610AM | Plasma | Ok | |
| 9 | 11:07:41:310AM | Plasma | Ok | |
| 10 | 11:20:47:310AM | Plasma | Ok | |
| 11 | 11:30:11:940AM | Plasma | Ok | |
| 12 | 11:40:27:440AM | Plasma | Ok | |
| 13 | 11:58:24:410AM | Plasma | Ok | |
| 14 | 12:06:46:700PM | Plasma | Ok | |
| 15 | 12:17:29:120PM | Plasma | Ok | |
| 16 | 12:29:05:330PM | Plasma | Ok | |
| 17 | 12:44:53:010PM | Plasma | Ok | |
| 18 | 12:55:09:390PM | Plasma | Ok | |
| 19 | 01:05:40:110PM | Plasma | Ok | |
| 20 | 01:16:26:920PM | Plasma | Ok | |
| 21 | 01:26:05:370PM | Plasma | Ok | |
| 22 | 01:38:27:390PM | Plasma | Ok | |
| 23 | 01:54:16:510PM | Plasma | Ok | |
| 24 | 02:04:44:740PM | Plasma | Ok | |
| 25 | 02:12:47:190PM | Plasma | Ok | |
| 26 | 02:21:55:260PM | Plasma | Ok | |
| 27 | 02:33:16:990PM | Plasma | Ok | |
| 28 | 02:43:35:910PM | Plasma | Ok | |
| 29 | 03:01:17:650PM | Plasma | Ok | |
| 30 | 04:00:25:530PM | Plasma | Ok | |
| 31 | 04:24:48:990PM | Plasma | Ok | |
| 32 | 04:36:26:070PM | Plasma | Ok | |
| 33 | 04:44:59:600PM | Plasma | Ok | |
| 34 | 04:54:33:550PM | Plasma | Ok | |
| 35 | 05:01:50:830PM | Plasma | Ok | |
| 36 | 05:47:35:200PM | Test | Ok | josh test |
| 37 | 05:54:59:280PM | Test | Ok | josh |