| Miniproposals | ||||||||||
|
| Operators | |
| Session leader(s): | Steve Wolfe |
| Physics operator(s): | Jim Irby |
| Engineering operator(s): | Bill Byford,Bill Cochran,Bill Parkin |
| Engineering Operator Run Comment |
| Plasma Conditioning--DNB Testing--Power System Tests (EF2). Irby/Wolfe/C |
| Session Leader Plans |
| Physics Operators Plans |
| Session Leader Summaries |
| Entered: Jul 7 2004 03:49:26:133PM |
| Author: To Be Determined |
| Session Leader's Summary for Thursday, May 24, 2001 (1010524) Plasma Conditioning DNB Testing Power System Tests (EF2) SL: Wolfe PO: Irby EO: Cochran,Byford,Parkin The main goals of this run are 1) Begin the long, dreary process of cleaning up the machine using tokamak discharges 2) Continue the beam-into-gas (with TF) DNB testing, and determine the max allowable neutral pressure An additional goal, time and conditions permitting, is to complete the power systems tests to document the EF2 response in the vicinity of 60Hz, as a first step in dealing with the 60Hz oscillations observed during double barrier experiments on 1001220. Plan: ----- 1) Begin with a reverse bridge Tuesday test, with TF, similar to 1010516006, to check, and hopefully lower, the coax resistance. TF, 150Kamps, 1600V, PLC OH1, -10Kamps, -1000V, PLC OH2U-L, -10Kamps, -300V, PLc OH PLC Fizzle Delay disabled TF PLC Fizzle Delay set to 100msec from 600msec. 2) Plasma attempt, as on 1010516001, except fizzle delay on OH's to 700msec, fizzle delay on TF to 800msec *PLC current limit on reverse bridge on all oh supplies to -20KA The increases in the fizzle delay are to allow a larger double swing on the OH1 and OH2L, in order to keep the coax resistance from increasing on fizzles. We should look at the results on the first fizzle we get, and may decide to change these delays. *Reducing the reverse bridge current limit is to keep the reverse swing from getting too large unnecessarily. We should leave this limit in place until we start getting plasmas long enough to rail one of the supplies; then we can consider going back to -26,-27,-27, as on 1010516001. If a plasma is obtained proceed to step 3, otherwise, tweak startup and repeat until we get a plasma, assuming no problem with OH coaxes. 3) Following a successful plasma attempt, begin ECDC between shots in D2, then for the next one hour do the following a) If DNB is ready, go to TF and pulsed gas shots for approximately one hour. The following settings should be used: TF to 150KA under PLC control inverting at .5sec fizzle detector gate set to 0.38sec pulsed gas from B-top (hybrid control waveform as requested by DNB operators). Other pulsed gas valves disabled. Continue TF tests for one hour, varying gas puff as requested by DNB. It would be nice if at least one TF shot were extended to have at least a one second flattop, for magnetics "tilt" calibration. b) If DNB not ready, then begin EF2 frequency response tests: EF2 setup as on a normal shot (hybrid control); everything else off. PCS setup as prepared by Granetz in PCS_1010515000 for a 60Hz sinewave (this shot is also stored in USER10:[WOLFE.MDS.SHOTS.HYBRID.PCS]PCS_1010524666 A scope with other frequencies set up by Bob for pasting is in USER10:[wolfe.scopes]sinewaves.dat Do tests at 40, 50, 60, and 70 Hz. Perhaps do the 60 Hz case with and without current feedback on the EF2 during the oscillation, to see if a resonant instability is excited. Continue to ECDC between test shots. After one hour has elapsed, ->Go back to plasma attempts (as in step 2). Repeat this sequence (plasma , tests for an hour, plasma) until long plasmas are obtained or we run out of useful test shots. Then go to straight plasma attempts, with between-shot ECDC. If we start getting into warnings on the coax resistance, we may want to repeat the modified Tuesday test (step 1) or even increase the reverse oh current to -15 or -20kA, with the pulse width reduced by I^2 to keep the energy dissipated the same. ---------------------------------------------------------------------------- Results: We got off to a late start because PC network problems prevented the cooling from getting started until nearly 0900. Shot 1 was the TF/OH test shot. The OH2L coax resistane went up to 1.7uOhm during the TF rise, and stayed high. This was not what we hoped for. Shot 2 was a 250msec plasma at 600kA (800 programmed). #3-6 were EF2 wiggle tests (step 3b) at 60 and 40Hz. The EF2 response does seem to have a lag of order 8-10msec. Turning on the curent feedback did not result in any resonance amplification effects. There was also no obvious non-linearity up to 50V amplitude. The lag did seem to depend on whether or not the feedback was on, which is not presently understood. #7-9 were plasma attempts. #7 fizzled, #8 went for 310msec, 630kA, despite )or because of?) a gas failure; only the beam gas was present, with breakdown at 0.027mTorr! On #9, the gas worked again, and we had a fizzle. #10-13 were DNB beam-into-gas w/TF shots (step 3a); on #13 the DNB had a modreg problem. Up to .2mTorr there was no sign of runaway reionization and the MSE signal increased with gas pressure. #14-17 plasma attempts: #14 ran for 400msec. #15 fizzled, with bounces. #16 ran to 360msec #17 fizzled - too much gas after pre-puff was increased and the dnb came back on. Summary: ------------- Good progress on all of today's goals: We seem to be making pretty good progress in the clean-up: four plasmas ran today, and we ended up in the alternating fizzle sequence. It seems to like low fill pressures, although we were getting some runaways. The EF2 response is confirmed to be out of phase at 60Hz, but no resonant effect is evident with the feedback loop closed (for ef2 current). It might be interesting to complete the testing at other frequencies, but this is low priority. Once plasma operation is back to normal, we should experiment with the CLEARIN gain program to see if we can limit the 60 cycle postion oscillation observed in December. The dnb had a problem with the mod-reg on shot 13, but it was fixed at the end of the day, so they should be ready to continue beam-into-gas tomorrow. Problems: --------- The Paragon stations had a network problem which started last night. One of the CRYO stations is still not working, and a development station had to be used in its place. We had one unexplained gas system failure (shot 8) on which none of the valves got voltage. We also had one gas camac problem (shot 11) which shifted the signals. The OH2L coax resistance hovered around 2uOhm all day, but seems to be coming back down. The pf breaker pulled on OH1 crowbars on a couple of the disruptions. This may have been related to the fact that the disruption occurred during crossover. No fuses or devices were blown. |
| Physics Operator Summaries |
| Entered: Jul 7 2004 04:37:13:020PM |
| Author: To Be Determined |
| Plasma Conditioning --- DNB Testing --- Power System Tests (EF2) Start from OH/TF test shot 1010516006 OH/TF Fizzle delays at 700 and 800 ms ECDC in D2 at 2e-4 Torr, overnight. Be prepared for ECDC between shots Gas setup: fill B-top with 6 psi of D2 Hybrid Enable fill B-side lower with 1 psi of Ar Hybrid DISABLED fill B-side upper with nothing Hybrid DISABLED fill C-side with 30 psi of D2 Hybrid Enable fill J-bottom with nothing Hybrid DISABLED Please have XMTR 1, 2, 3, and 4 warmed up by run startup (9:00) Run starts at 09:00 and ends at 17:00. Results: We had four plasmas today. We found that prefill pressures from .026 to 0.11 mTorr were acceptable for producing plasmas. On shot 8 only the DNB gas (H2) provided the prefill since we had a problem with the gas system PLC. We got several useful shots for the EF2 and MSE/DNB tests. Problems: OH2L coax was over 2 uOhms on several shots but was coming down at the end of the run (as low as 1.25 uOhms). PLC problem with gas system needed to be looked at Run was delayed 2 hours because of an engineering PC network failure. PLCs continued to function properly. DNB had a DNB mod/reg problem that made them miss a shot or two. TCI lost some data on a fizzle shot as the plasma beam drifted into the port wall. Score: Plasmas 04 Fizzles 04 EF2 Tests 05 DNB shots 04 Details: Entry display output on Thu May 24 17:21:46 2001 ---------------------------------------------------------------------------- 1010524xxx irby PHYSICS_OPERATOR May 24 2001 8:21:36:450AM . . . . . . . . . . . . . . . . . . . . We had several problems over the last 24 hours that may affect today's run: . We lost the HEAT scanner yesterday afternoon when a 5 volt supply failed. The machine cooled down to -34C before it could be fixed and the f-port inner seal opened up enough to bring the m28 line up from 3e-9 to 6e-8 or so. When the problem was fixed the seal closed back up. . A PC network failure kept us from running overnight ECDC. Since we had been doing antenna and DNB conditioning most of the day, so cleanup of the vessel is probably needed. . We again lost network communications between the engineering PCs sometime during the night. So we were unable to cool or do ECDC this morning. Did cold start --- All okay ---------------------------------------------------------------------------- 1010524xxx irby PHYSICS_OPERATOR May 24 2001 9:20:47:436AM . . . . . . . . . . . . . . . . . . . . We have run several 100 amp tests of the OH2L coax resistance since last Wed, 5/16/01, at temps from -40 to -172C. All measurements were below 1 uOhm. The -172C measurement was about 0.7 uOhm. ---------------------------------------------------------------------------- 1010524xxx irby PHYSICS_OPERATOR May 24 2001 10:01:43:736AM . . . . . . . . . . . . . . . . . . . . We ran ECDC for approx 1 hour after the network problems were fixed. M18, M20, M28, and M32 were at the same levels as on Wed morn, so the wall/vacuum conditions are probably not much worse. ---------------------------------------------------------------------------- 1010524001 irby PHYSICS_OPERATOR May 24 2001 10:57:04:060AM . . . . . . . . . . . . . . . . . . . . This shot will be a OH/TF test. OH2L coax resistance started out low, 1 uohm, but went up with TF field to 1.8 uohm (jXB ?) ---------------------------------------------------------------------------- 1010524002 irby PHYSICS_OPERATOR May 24 2001 11:20:02:246AM . . . . . . . . . . . . . . . . . . . . Loaded shot 1010516001 --- go for plasma Plasma to 250 ms, 650 kA OH2L coax to 1.88 uOhm, but much lower after crossover ---------------------------------------------------------------------------- 1010524003 irby PHYSICS_OPERATOR May 24 2001 11:52:51:276AM . . . . . . . . . . . . . . . . . . . . EF2 test --- 20 volt, 60 Hz, no gain ---------------------------------------------------------------------------- 1010524004 irby PHYSICS_OPERATOR May 24 2001 11:58:41:820AM . . . . . . . . . . . . . . . . . . . . EF2 test, 60 Hz, gain to 1.5 s ---------------------------------------------------------------------------- 1010524005 irby PHYSICS_OPERATOR May 24 2001 12:22:35:646PM . . . . . . . . . . . . . . . . . . . . Increased amp of 60Hz EF2 voltage to 50 V. ---------------------------------------------------------------------------- 1010524006 irby PHYSICS_OPERATOR May 24 2001 12:38:09:840PM . . . . . . . . . . . . . . . . . . . . loaded 40 Hz, 20 V EF2 drive voltage, gain off ---------------------------------------------------------------------------- 1010524007 irby PHYSICS_OPERATOR May 24 2001 1:08:36:633PM . . . . . . . . . . . . . . . . . . . . Try for plasma again Zeroed pulsed gas 3 in seg 2 Dropped peak density request to 5 from 7e19 Fizzle OH2l at 1.97 uOhms ---------------------------------------------------------------------------- 1010524008 irby PHYSICS_OPERATOR May 24 2001 1:39:32:990PM . . . . . . . . . . . . . . . . . . . . Reduced prefill by 2 ms. Took 100 ms off of TF and OH fizzle delays Plasma to 313 ms, 636 kA Looks like we had no prefill gas --- ran on beam gas? Time (ms): 0 5 10 25 ---------------------------------------- Ip (kA): -0.6059 -10.9826 -26.5475 -49.9177 dIp/dt (kA/ms): -0.8902 -2.5455 -1.7825 -4.7084 pressure (mTorr): 0.0276 0.0273 0.0267 0.0264 Bz0 (mT): -5.3863 -2.3016 -1.6593 17.3669 Br0 (mT): -0.5224 -0.7055 -0.6624 -1.3618 ---------------------------------------------------------------------------- 1010524009 irby PHYSICS_OPERATOR May 24 2001 2:06:56:980PM . . . . . . . . . . . . . . . . . . . . Repeat Fizzle --- did have gas OH2L 2.2 uohms --- below 2 well after crossover. ---------------------------------------------------------------------------- 1010524010 irby PHYSICS_OPERATOR May 24 2001 2:20:01:960PM . . . . . . . . . . . . . . . . . . . . Going to DNB part of run with TF and gas only okay --- got beam, got gas, got tf, got signal ---------------------------------------------------------------------------- 1010524011 irby PHYSICS_OPERATOR May 24 2001 2:43:03:520PM . . . . . . . . . . . . . . . . . . . . DNB asked to double pressure -- increased prefill from 20 to 50 ms. Looks good --- pressure at t=0 is 0.196 mTorr No beam! ---------------------------------------------------------------------------- 1010524012 irby PHYSICS_OPERATOR May 24 2001 2:59:54:066PM . . . . . . . . . . . . . . . . . . . . Repeat got beam, got pressure ---------------------------------------------------------------------------- 1010524013 irby PHYSICS_OPERATOR May 24 2001 3:27:25:680PM . . . . . . . . . . . . . . . . . . . . Beam guys want twice the gas again --- prefill from 50 to 110 ms ---------------------------------------------------------------------------- 1010524014 irby PHYSICS_OPERATOR May 24 2001 4:17:26:590PM . . . . . . . . . . . . . . . . . . . . Back to plasma loaded shot 1010524008 prefill to 10 ms plasma to 400 ms, 687 kA Time (ms): 0 5 10 25 ---------------------------------------- Ip (kA): 2.0109 -10.9826 -31.7358 -52.5118 dIp/dt (kA/ms): -1.2727 -3.3074 -1.5238 -4.0693 pressure (mTorr): 0.0345 0.0338 0.0342 0.0382 Bz0 (mT): -3.5796 -1.1148 0.3314 19.4679 Br0 (mT): -0.6415 -1.0946 -1.1789 -1.1901 ---------------------------------------------------------------------------- 1010524015 irby PHYSICS_OPERATOR May 24 2001 4:35:10:953PM . . . . . . . . . . . . . . . . . . . . Repeat Fizzle --- too little gas? Time (ms): 0 5 10 25 ---------------------------------------- Ip (kA): -0.6059 -10.9598 -29.1190 -18.7650 dIp/dt (kA/ms): -1.2716 -3.0509 -2.6727 0.5064 pressure (mTorr): 0.0342 0.0326 0.0345 0.0409 Bz0 (mT): -3.8138 -1.6167 0.2728 17.6506 Br0 (mT): -0.7118 -0.7254 -1.6033 -1.3341 Oh2l coax at 1.75 uohm ---------------------------------------------------------------------------- 1010524016 irby PHYSICS_OPERATOR May 24 2001 5:01:38:143PM . . . . . . . . . . . . . . . . . . . . Repeat Plasma for 364 ms, 675 kA OH2L coax 1.26 uOhm Time (ms): 0 5 10 25 ---------------------------------------- Ip (kA): -0.6059 -10.9598 -31.7358 -47.3008 dIp/dt (kA/ms): -1.2705 -3.0519 -1.7825 -4.1986 pressure (mTorr): 0.0330 0.0338 0.0361 0.0409 Bz0 (mT): -2.9851 -1.6224 -0.3284 19.5523 Br0 (mT): -0.6800 -0.5314 -1.1633 -1.2347 ---------------------------------------------------------------------------- 1010524017 irby PHYSICS_OPERATOR May 24 2001 5:17:00:423PM . . . . . . . . . . . . . . . . . . . . Increased prefill to 15 from 10 ms Fizzle --- too much gas! Time (ms): 0 5 10 25 ---------------------------------------- Ip (kA): -0.5832 -10.9598 -23.9534 -18.7650 dIp/dt (kA/ms): -1.0173 -2.4183 -1.2738 -0.3860 pressure (mTorr): 0.0929 0.0972 0.0929 0.0939 Bz0 (mT): -3.6074 -1.9033 0.0808 17.0638 Br0 (mT): -0.3342 -0.8882 -0.9219 -1.2369 OH2L coax 1.48 uOhms |
| Session Leader Comments | |||
| May 24 2001 08:23:03:517AM | Steve Wolfe | Run Plan for Thursday, 5/24/2001 Plasma Conditioning DNB Testing Power System Tests (EF2) SL: Wolfe PO: Irby The main goals of this run are 1) Begin the long, dreary process of cleaning up the machine using tokamak discharges 2) Continue the beam-into-gas (with TF) DNB testing, and determine the max allowable neutral pressure An additional goal, time and conditions permitting, is to complete the power systems tests to document the EF2 response in the vicinity of 60Hz, as a first step in dealing with the 60Hz oscillations observed during double barrier experiments on 1001220. Plan: ----- 1) Begin with a reverse bridge Tuesday test, with TF, similar to 1010516006, to check, and hopefully lower, the coax resistance. TF, 150Kamps, 1600V, PLC OH1, -10Kamps, -1000V, PLC OH2U-L, -10Kamps, -300V, PLc OH PLC Fizzle Delay disabled TF PLC Fizzle Delay set to 100msec from 600msec. 2) Plasma attempt, as on 1010516001, except fizzle delay on OH's to 700msec, fizzle delay on TF to 800msec *PLC current limit on reverse bridge on all oh supplies to -20KA The increases in the fizzle delay are to allow a larger double swing on the OH1 and OH2L, in order to keep the coax resistance from increasing on fizzles. We should look at the results on the first fizzle we get, and may decide to change these delays. *Reducing the reverse bridge current limit is to keep the reverse swing from getting too large unnecessarily. We should leave this limit in place until we start getting plasmas long enough to rail one of the supplies; then we can consider going back to -26,-27,-27, as on 1010516001. If a plasma is obtained proceed to step 3, otherwise, tweak startup and repeat until we get a plasma, assuming no problem with OH coaxes. 3) Following a successful plasma attempt, begin ECDC between shots in D2, then for the next one hour do the following a) If DNB is ready, go to TF and pulsed gas shots for approximately one hour. The following settings should be used: TF to 150KA under PLC control inverting at .5sec fizzle detector gate set to 0.38sec pulsed gas from B-top (hybrid control waveform as requested by DNB operators). Other pulsed gas valves disabled. Continue TF tests for one hour, varying gas puff as requested by DNB. It would be nice if at least one TF shot were extended to have at least a one second flattop, for magnetics "tilt" calibration. b) If DNB not ready, then begin EF2 frequency response tests: EF2 setup as on a normal shot (hybrid control); everything else off. PCS setup as prepared by Granetz in PCS_1010515000 for a 60Hz sinewave (this shot is also stored in USER10:[WOLFE.MDS.SHOTS.HYBRID.PCS]PCS_1010524666 A scope with other frequencies set up by Bob for pasting is in USER10:[wolfe.scopes]sinewaves.dat Do tests at 40, 50, 60, and 70 Hz. Perhaps do the 60 Hz case with and without current feedback on the EF2 during the oscillation, to see if a resonant instability is excited. Continue to ECDC between test shots. After one hour has elapsed, ->Go back to plasma attempts (as in step 2). Repeat this sequence (plasma , tests for an hour, plasma) until long plasmas are obtained or we run out of useful test shots. Then go to straight plasma attempts, with between-shot ECDC. If we start getting into warnings on the coax resistance, we may want to repeat the modified Tuesday test (step 1) or even increase the reverse oh current to -15 or -20kA, with the pulse width reduced by I^2 to keep the energy dissipated the same. | |
| May 24 2001 08:23:13:733AM | Steve Wolfe | We are probably going to be starting a bit late due to a problem on the Engineering PC/PLC network. When we do get started, we will be doing the EF2 tests (step 3b) in the morning. Rowan has requested that the DNB tests (3a in the run plan) be done in the afternoon. | |
| May 24 2001 10:55:08:540AM | 1010524001 | Steve Wolfe | Shot#1: TF and reverse bridge OH "Tuesday" test OH2L resistance increases to 1.8uOhm during the shot. next shot: plasma attempt |
| May 24 2001 11:20:24:090AM | 1010524002 | Steve Wolfe | Shot#2: plasma attempt, PCS load from 1010516001 plasma to 250msec, 600kA TCI analysis failed again. We should back way down on the seg2 gas puff, both the V and the demand. We will ECDC between shots, and do the EF2 tests next. |
| May 24 2001 11:41:49:613AM | 1010524003 | Steve Wolfe | Shot#3: EF2 wiggle test. Start from pre-program in 1010515000 (60Hz starting at -.2sec, feedback off at -0.2sec, in seg 2) 180 degreees out of phase. Next shot, try turning the feedback on. |
| May 24 2001 12:13:40:550PM | 1010524004 | Steve Wolfe | Shot#4: Extend ef2u,l feedback control. The current perturbation from 20V is so small it may not make any difference, but I want to see if it resonates and grows. OK, I can just see it on the current. The first cycle has larger demand, but it seems to settle down to about +/- 25volts or so. The demand jump is because the feed-forward offset in seg1 is absent in seg2. It's not obviously broken at this level. Next shot: try increasing thw amplitude to 50V at 60Hz. |
| May 24 2001 12:28:52:877PM | 1010524005 | Steve Wolfe | Shot#5: try increasing thw amplitude to 50V at 60Hz with feedback between 15 and 20A perturbation on the current this time. hybrid demand is +/- 50V, as programmed, and the response is the same still out of phase, so no runaway on demand and no resonant behavior. Actually, it looks more like a 10msec lag here; at the lower frequency it really was 8.8msec; it is longer when the feedback is turned on, also on shot 4. Next shot: 40Hz, no feedback. |
| May 24 2001 12:45:51:480PM | 1010524006 | Steve Wolfe | Shot#6: 40Hz, no feedback. about 8-10msec delay next shot: Back to plasma attempts. reload 1010524002 turn off pg3 voltage in seg 2, and change nl04 from 7e19 to 5e19 |
| May 24 2001 01:06:44:007PM | 1010524007 | Steve Wolfe | Shot#7: fizzle. So much for waiting an hour and a half. pressure is .09mTorr; on shot 2 it was .11mTorr!!!! oh2l coax resistance is up to 1.97uOhm, but Jim says it went down at the end of the shot. next shot: reduce pre-puff and try again |
| May 24 2001 01:39:02:693PM | 1010524008 | Steve Wolfe | Shot#8: reduce pre-puff and try again plasma to 310msec, 630kA; a few runaways. It looks like we got no gas from the valves on this shot. The hv waveforms are zero, and the pressure at t=0 was 0.027mTorr; the rise on the ratiomatic starts at -.6, possibly from the beam source. Shot 2 was the highest pressure breakdown I've seen, and shot 8 was the lowest! coax resistance at 1.98uOhm this time, next shot: another plasma attempt, just for the fun of it. |
| May 24 2001 01:53:39:407PM | 1010524009 | Steve Wolfe | Shot#9: : another plasma attempt, just for the fun of it. fizzle, got gas this time, .09mTorr oh2L coax at 2.2uOhms next shot: beam into gas for DNB |
| May 24 2001 02:25:39:407PM | 1010524010 | Steve Wolfe | Shot#10: beam into gas for DNB. Ratiomatic says .1mTorr at t=0 DNB seems to be missing some camac signals. next shot: try to double the pressure - go to 50msec |
| May 24 2001 02:42:55:003PM | 1010524011 | Steve Wolfe | Shot#11: try to double the pressure - go to 50msec Got 0.2mTorr; gas camac screwed up, pulse shows up on the wrong valve. Beam arced out. need to do this one again (with beam). |
| May 24 2001 03:06:43:050PM | 1010524012 | Steve Wolfe | Shot#12: repeat at 50msec, hoping for beam. Got beam, Howard says he sees more signal. next shot: double gas again |
| May 24 2001 03:29:02:857PM | 1010524013 | Steve Wolfe | Shot#13: double gas again No beam, modreg not triggering p0=.375mTorr next shot: back to plasma attempts. like shot#8, pre-puff to 10msec |
| May 24 2001 04:09:27:963PM | 1010524014 | Steve Wolfe | Shot#14: back to plasma attempts. like shot#8, pre-puff to 10msec plasma, 400msec, 670kA; this one sawtooths. Diverted at 0.25sec. This one is going along fine until an injection at 0.379sec startup is slightly ratty. p0=0.034mTorr, a bouncer. coax to 1.7uOhm DNB is down for the day with a modreg problem. next shot: try again. |
| May 24 2001 04:23:10:287PM | 1010524015 | Steve Wolfe | Shot#15: fizzle; bounced twice. next shot: raise pre-puff to 15msec |
| May 24 2001 04:50:56:107PM | 1010524016 | Steve Wolfe | Shot#16: forgot to raise pre-puff to 15msec plasma, 361msec,672kA. More hards. One bounce. |
| May 24 2001 04:51:31:217PM | 1010524016 | Steve Wolfe | Shot#16: forgot to raise pre-puff to 15msec plasma, 361msec,672kA. More hards. One bounce. next shot: one more try |
| May 24 2001 05:11:49:583PM | 1010524017 | Steve Wolfe | Shot#1: raise pre-puff to 15msec fizzle. p0 went to .095mTorr - beam was back on. |
| Physics Operator Comments | |||
| May 24 2001 08:21:36:450AM | Jim Irby | We had several problems over the last 24 hours that may affect today's run: . We lost the HEAT scanner yesterday afternoon when a 5 volt supply failed. The machine cooled down to -34C before it could be fixed and the f-port inner seal opened up enough to bring the m28 line up from 3e-9 to 6e-8 or so. When the problem was fixed the seal closed back up. . A PC network failure kept us from running overnight ECDC. Since we had been doing antenna and DNB conditioning most of the day, so cleanup of the vessel is probably needed. . We again lost network communications between the engineering PCs sometime during the night. So we were unable to cool or do ECDC this morning. Did cold start --- All okay | |
| May 24 2001 09:20:47:437AM | Jim Irby | We have run several 100 amp tests of the OH2L coax resistance since last Wed, 5/16/01, at temps from -40 to -172C. All measurements were below 1 uOhm. The -172C measurement was about 0.7 uOhm. | |
| May 24 2001 10:01:43:737AM | Jim Irby | We ran ECDC for approx 1 hour after the network problems were fixed. M18, M20, M28, and M32 were at the same levels as on Wed morn, so the wall/vacuum conditions are probably not much worse. | |
| May 24 2001 10:57:04:060AM | 1010524001 | Jim Irby | This shot will be a OH/TF test. OH2L coax resistance started out low, 1 uohm, but went up with TF field to 1.8 uohm (jXB ?) |
| May 24 2001 11:20:02:247AM | 1010524002 | Jim Irby | Loaded shot 1010516001 --- go for plasma Plasma to 250 ms, 650 kA OH2L coax to 1.88 uOhm, but much lower after crossover |
| May 24 2001 11:52:51:277AM | 1010524003 | Jim Irby | EF2 test --- 20 volt, 60 Hz, no gain |
| May 24 2001 11:58:41:820AM | 1010524004 | Jim Irby | EF2 test, 60 Hz, gain to 1.5 s |
| May 24 2001 12:22:35:647PM | 1010524005 | Jim Irby | Increased amp of 60Hz EF2 voltage to 50 V. |
| May 24 2001 12:38:09:840PM | 1010524006 | Jim Irby | loaded 40 Hz, 20 V EF2 drive voltage, gain off |
| May 24 2001 01:08:36:633PM | 1010524007 | Jim Irby | Try for plasma again Zeroed pulsed gas 3 in seg 2 Dropped peak density request to 5 from 7e19 Fizzle OH2l at 1.97 uOhms |
| May 24 2001 01:39:32:990PM | 1010524008 | Jim Irby | Reduced prefill by 2 ms. Took 100 ms off of TF and OH fizzle delays Plasma to 313 ms, 636 kA Looks like we had no prefill gas --- ran on beam gas? Time (ms): 0 5 10 25 ---------------------------------------- Ip (kA): -0.6059 -10.9826 -26.5475 -49.9177 dIp/dt (kA/ms): -0.8902 -2.5455 -1.7825 -4.7084 pressure (mTorr): 0.0276 0.0273 0.0267 0.0264 Bz0 (mT): -5.3863 -2.3016 -1.6593 17.3669 Br0 (mT): -0.5224 -0.7055 -0.6624 -1.3618 |
| May 24 2001 02:06:56:980PM | 1010524009 | Jim Irby | Repeat Fizzle --- did have gas OH2L 2.2 uohms --- below 2 well after crossover. |
| May 24 2001 02:20:01:960PM | 1010524010 | Jim Irby | Going to DNB part of run with TF and gas only okay --- got beam, got gas, got tf, got signal |
| May 24 2001 02:43:03:520PM | 1010524011 | Jim Irby | DNB asked to double pressure -- increased prefill from 20 to 50 ms. Looks good --- pressure at t=0 is 0.196 mTorr No beam! |
| May 24 2001 02:59:54:067PM | 1010524012 | Jim Irby | Repeat got beam, got pressure |
| May 24 2001 03:27:25:680PM | 1010524013 | Jim Irby | Beam guys want twice the gas again --- prefill from 50 to 110 ms |
| May 24 2001 04:17:26:590PM | 1010524014 | Jim Irby | Back to plasma loaded shot 1010524008 prefill to 10 ms plasma to 400 ms, 687 kA Time (ms): 0 5 10 25 ---------------------------------------- Ip (kA): 2.0109 -10.9826 -31.7358 -52.5118 dIp/dt (kA/ms): -1.2727 -3.3074 -1.5238 -4.0693 pressure (mTorr): 0.0345 0.0338 0.0342 0.0382 Bz0 (mT): -3.5796 -1.1148 0.3314 19.4679 Br0 (mT): -0.6415 -1.0946 -1.1789 -1.1901 |
| May 24 2001 04:35:10:953PM | 1010524015 | Jim Irby | Repeat Fizzle --- too little gas? Time (ms): 0 5 10 25 ---------------------------------------- Ip (kA): -0.6059 -10.9598 -29.1190 -18.7650 dIp/dt (kA/ms): -1.2716 -3.0509 -2.6727 0.5064 pressure (mTorr): 0.0342 0.0326 0.0345 0.0409 Bz0 (mT): -3.8138 -1.6167 0.2728 17.6506 Br0 (mT): -0.7118 -0.7254 -1.6033 -1.3341 Oh2l coax at 1.75 uohm |
| May 24 2001 05:01:38:143PM | 1010524016 | Jim Irby | Repeat Plasma for 364 ms, 675 kA OH2L coax 1.26 uOhm Time (ms): 0 5 10 25 ---------------------------------------- Ip (kA): -0.6059 -10.9598 -31.7358 -47.3008 dIp/dt (kA/ms): -1.2705 -3.0519 -1.7825 -4.1986 pressure (mTorr): 0.0330 0.0338 0.0361 0.0409 Bz0 (mT): -2.9851 -1.6224 -0.3284 19.5523 Br0 (mT): -0.6800 -0.5314 -1.1633 -1.2347 |
| May 24 2001 05:17:00:423PM | 1010524017 | Jim Irby | Increased prefill to 15 from 10 ms Fizzle --- too much gas! Time (ms): 0 5 10 25 ---------------------------------------- Ip (kA): -0.5832 -10.9598 -23.9534 -18.7650 dIp/dt (kA/ms): -1.0173 -2.4183 -1.2738 -0.3860 pressure (mTorr): 0.0929 0.0972 0.0929 0.0939 Bz0 (mT): -3.6074 -1.9033 0.0808 17.0638 Br0 (mT): -0.3342 -0.8882 -0.9219 -1.2369 OH2L coax 1.48 uOhms |
| Engineering Operator Comments | ||||
| Shot | Time | Type | Status | Comment |
| 1 | 10:42:30:767AM | Test | Ok | OH Coax Test, oh2l 1.8uohms |
| 2 | 11:06:25:343AM | Plasma | Ok | All Systems Fired |
| 3 | 11:29:11:950AM | Test | Ok | EF2U-L Test only |
| 4 | 11:54:47:470AM | Test | Ok | EF2 Test only |
| 5 | 12:16:49:747PM | Test | Ok | EF2 Test only |
| 6 | 12:35:45:117PM | Test | Ok | EF2 Test only |
| 7 | 12:51:57:243PM | Plasma | Ok | All Power Supplies Fired |
| 8 | 01:19:07:013PM | Plasma | Ok | |
| 9 | 01:43:41:000PM | Plasma | Ok | |
| 10 | 02:12:42:320PM | Test | Ok | |
| 11 | 02:37:11:320PM | Test | Ok | |
| 12 | 02:55:21:057PM | Test | Ok | |
| 13 | 03:24:06:270PM | Test | Ok | |
| 14 | 03:53:21:827PM | Plasma | Ok | |
| 15 | 04:18:46:750PM | Plasma | Ok | |
| 16 | 04:42:25:340PM | Plasma | Bad | OH1 self power cir. fired, PF brkr opened |
| 17 | 05:06:47:983PM | Plasma | Ok | |