Alcator C-Mod Run 970605 Information

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Miniproposals
Miniproposal:171a
Date Filed: 5/21/1997
Title:40MHz RF Conditioning and Testing
First Author:Yuichi Takase
Session Leader:Steve Wukitch (shots 1-32)
Miniproposal:178
Date Filed: 5/20/1997
Title:Preliminary 40MHz Mode Conversion Current Drive
First Author:Steve Wukitch
Session Leader:Steve Wukitch (shots 1-32)

Operators
Session leader(s):Steve Wukitch,Steve Wukitch
Physics operator(s):Steve Wolfe
Engineering operator(s):Dave Terry,Frank Silva,Bill Cochran,Vinny Bertolino

Engineering Operator Run Comment
CONTINUE WITH STARTUP RESTART

Session Leader Plans

Physics Operators Plans

Session Leader Summaries
Entered: Jul 7 2004 03:49:16:727PM
Author: To Be Determined
The plan is to continue with MP171A (40 MHz RF testing and conditioning) with
D(He3) plasmas. Transmitters #3 and #4 were tested into dummy load (1 MW into
dummy load) prior to the session. He3 is ready for use.

The top priority is to get both transmitters broadcasting into plasmas with
powers up to 1 MW each and running together. Measuring the effectiveness of
the decoupler stub is another. MP178 will be explored to some extent depending
upon the success of the decoupling. To facilitate RF operations, plasma
discharges will be similar if not the same except for minor adjustments.

In contrast to yesterday, the run was productive. We were able to run both
transmitters to 1 MW by the end of the day (discharge 970605026 2 MW total for
50 msec). Although the heating efficiency is low due to the condition of the
plasma and antenna, the GPC showed electron heating on several discharges.
Two attempts were made to change the antenna phasing, but preliminary
measurements suggest the decoupling stub position is incorrect. The amount of
He3 injection was varied, but the concentration values were unknown.
Furthermore the amount injected is probably small. The H/(H+D) ratio climbed
to > 50% with a few shots and remained high throughout the session.

Shot

01-05 gas tests
06 pl n_el = 0.7 x 10^20, I_p ~ 0.8 MA, B_T = 5.4 -> 4.0 T, P_rf=0.9 MW but
mostly FMIT#3
07 pl disrupt @1.14 P_rf=0.9 MW but still mostly FMIT#3
08 pl both FMIT#3 and #4 run independently to P_rf=0.9 MW; changed B_T =
5.4->4.3 T
09 pl He3 delt_t= 0.1s
10 pl He3 delt_t= 0.2s
11 dud
12 test
13 pl no He3
14 pl He3 back on; P_rf = 0.8 MW
15 pl FMIT#3 and #4 ran simultaneously
16 pl sharkfin (unexplained density rise) and disrupted @0.4 sec
17 pl disrupt @ ~1 s ramped RF power to 1.5 MW
18 pl disrupt @ ~1 s ramped RF power to 1.6 MW
19 dud increased He3 (del_t = 0.3 s) spurious magnet resistance fault (only
EF2 and EFC supplies fired)
20 fiz larger outer gap
21 fiz
22 dud put pi/2 phase delay in FMIT#4
23 pl disrupt @1.15 P_rf = 1 MW total
24 pl removed pi/2 delay and put pi phase delay in FMIT#4; P_rf=0.8 MW
25 pl P_rf=1.0 MW FMIT#4 only
26 pl P_rf=2.0 MW
27 pl FMIT#4 faulted
28 fiz
29 pl disrupt @0.37 s
30 fiz
31 pl FMIT#4 crowbar
32 no RF

Physics Operator Summaries
Entered: Jul 7 2004 04:36:57:550PM
Author: To Be Determined
Physop Summary for 970605

SL: Wukitch
PO: wolfe
EO: Silva,Cochrane/Terry,Bertolino

MP: 171A RF conditioning

The main goal is to get power into the machine from both transmitters and to
try to get them to run together. Heating mode is supposed to be D(He3) in the
vicinity of 4T.

Run plan:

Overnight ECDC in D2.

Engineering setup as on 970604047; TF under hybrid control.

Gas setup - hybrid enable the following valves
fill K-side with 20 PSI of D2
fill B-top with 5 PSI of D2
Fill but do not enable: B-side-lower with 4 PSI of Ar
B-side-upper should still have He3 - DO NOT PURGE!

Note: there is a possible problem with the B-side-upper gas board. J. Goetz
has sent e-mail to Willy Burke about this. It may be necessary to run some
test cycles with someone in the cell before the start of the run to check this
out.

Enable ECE, PCX, TCX, VUV, Moly gate valves if their vacuums are acceptable.

The run will start out with MP 170A (startup) and MP171A (RF conditioning).
We may also try to use the cryopump prototype (MP 160).

Session leader Takase has the option of starting an experiment outlined in OPS
bulletin.

Results:
--------

There was in fact a problem with the B-side-upper. It turned out, after a lot
of thrashing, including several test shot cycles, that the piezo is deceased;
it had a resistance of 5.6 ohm, which also explains the low voltage observed
on the digitizer yesterday. It turns out the old board had a 1K limiting
resistor and the one Willy swapped in today had 10K, so the voltage appeared
to go back to the right level, but the valve was essentially a short.

The RF team had lots of work to do this morning, so they were not delayed due
to the testing, but it was necessary to find an alternate source for the
He3. It was decided to pulse through the NINJA system, where they also had a
spectrometer set up to look at He plumes (by an odd coincidence). In order to
get this to work, it was necessary to replace the PLC connection to the
B-side-upper plenum and use that plenum to fill the lower divertor
plenum. This results in each plenum having half the original fill. The PLC
connection back to the He3 bottle is now disconnected to prevent the bottle
from getting accidentally pumped away.

The run was fairly successful in that we got a lot of plasmas and the RF got
up to 2MW, with both transmitters running together. The attempt to cool the
cryopump was unsuccessful, and the RF group did not manage to adjust the
relative phasing of the straps. H/(H+D) was around 40% early in the day and
rose to 60% by the end.

Details:
---------
The first five shots were tests of the gas board and piezo on b-side-upper.

The run proper started at 11AM, with shot #6. Shots 6 and 7 ran, but were
runaway discharges. Moving the PG3 segment 1 gas puff to start at t=0 did not
help the runaway problem. RF #3 ran well on these shots (1MW) and #4 was in
there at ~100kW.

On shot #8 I both raised the fill and made ICef4 more positive by 10A. I
believe it is the EF4 tweak that cured the runaways, but I can't prove it.
Also on #8 the tf second flattop was raised from -107500A to -116kA, aiming
for 4.3T instead of 4 (for D(He3) mode conversion).

Shot#9 was the first shot with He3 from NINJA, shot #10 had more He3.

Shot #11 was a hybrid dud! The wavegen put out funny glitchy target signals,
and the supplies ended up close to where they were supposed to be but not
close enough. A hybrid-only test shot did not reproduce the problem, and
neither did an open-circuit test on shot#12. We decided it was a glitch and
continued.

Shot 13 I changed the ZXL program to ramp down, to try to get the strike
points to stay around probe 4 for Blip. This succeeded in keeping the strike
points more constant, but between probe 6 and 7, which is higher than Bruce
wanted it.

Shot 14 was preceded by a cell access to start the cryopump. Shot 15 was a
repeat; the RF transmitters ran together on this one for the first(?) time.
The cryopump cooled very slowly, indicating problems in LHe transfer;
eventually this part of the run was abandoned.

Shot 16 was supposed to be a repeat but had an early sharkfin (or other
unexplained density ramp) and disrupted around OH1 crossover.

Shots 17-18 disrupted with injections around 1sec. The RF was getting to 1.5MW
and the antenna tiles were glowing after the shot.

Shot 19 was a "magnet resistance fault" dud (only EF2 and EFC supplies fired).

Shot 20-21 were fizzles with late breakdowns. A Br tweak did not help 19, but
it was left in.

Shot 22 was the second Wavegen dud of the day. This time was a repeat of the
thing it did last week, with no signals at all out of the wavegen, so the
supplies only came on to low levels based on offsets and Br feeback. Again, a
hybrid-only test shot was ok.

Shots 23-27 were plasmas, with RF getting better. 23 disrupted around 1.15
sec, the others lasted to 1.4-1.5. I tried several tweaks to try to extend
rampdown, but nothing did much good. Note that one thing I did was delay the
switch in RCUR offset (from 8000 to 6000) from 1.4 sec to 1.6 sec. This didn't
seem to have much effect on shot length.

Shot 28 was a fizzle with a late breakdown. On shot 29 I delayed the PG3
segment 1 gas puff, which had been moved earlier on shot 6 and not put back,
and got a plasma that disrupted with an injection at .37 sec.

#30 was a bouncing fizzle, presumably disruption recovery.

Shot #31 was a plasma of about the same length as the other long ones; the RF
got to 2MW, but trans #4 crowbarred.

Shot #32 was the same programming, but with no RF and the Ar puff turned off,
to see if the pulse length would be increased. It ran to the same length.

Comments:
--------
Power systems ran well, except for one disruption-induced OH1 crowbar. We had
one PLC glitch (magnet resistance fault) that cost a shot. There were two
hybrid problems, both involving the wavegen; if these continue, it may be
worthwhile to try going back to J221 timing instead of the internal timing as
it is presently set up.

The b-side-upper piezo will need to be replaced over the maintenance week, one
way or the other.

Cryopump transfer problems may be debugged by tomorrow's run?

Startup reliability was quite good today, with the only duds being power
supply/hybrid related. There were 4 fizzles, some of which may have been
"disruption recovery".

The first two runaway discharges were fixed by making the EF4 current more
positive, or by raising the pre-puff; I think the former.

Cooling was working well, and we could have gotten more shots if the RF guys
didn't think so much.

Scorecard:
---------
Tests 6
Duds 3 (2 hybrid, one PLC)
fizzles 4
plasmas 19
------ --
total 32

Raw startup fraction = 19/26 = 73%
Useable plasmas 17 (including 2 with early runaways)
Not too bad for an 11AM start.

Session Leader Comments
Jun 9 1997 07:47:48:710AMSteve WukitchThe plan is to continue with MP171A (40 MHz RF testing and conditioning) with
D(He3) plasmas. Transmitters #3 and #4 were tested into dummy load (1 MW into
dummy load) prior to the session. He3 is ready for use.

The top priority is to get both transmitters broadcasting into plasmas with
powers up to 1 MW each and running together. Measuring the effectiveness of
the decoupler stub is another. MP178 will be explored to some extent depending
upon the success of the decoupling. To facilitate RF operations, plasma
discharges will be similar if not the same except for minor adjustments.
Jun 9 1997 07:49:38:250AMSteve WukitchShots 01-05 were He3 gas tests.
Jun 9 1997 07:56:34:510AM970605006Steve Wukitchplasma n_el ~ 1 x 10^20, I_p ~ 0.8 MA, B_T = 5.4 -> 4.0 T, P_rf=0.9 MW but mostly FMIT#3,
FMIT#4 was ~100 kW, no He3
Jun 9 1997 07:59:11:120AM970605007Steve Wukitchplasma disrupt @1.14s, P_rf=0.9 MW again mostly from FMIT#3
working on match so FMIT#3 and #4 run together
Jun 9 1997 08:00:59:050AM970605008Steve Wukitchplasma both FMIT#3 and #4 run independently to P_rf=0.9 MW; ramped B_T to 4.3 T
Jun 9 1997 11:05:59:910AM970605009Steve Wukitchplasma puffed He3 through NINJA (delt_t= 0.1s)

Jun 9 1997 11:06:25:140AM970605010Steve Wukitchplasma puffed He3 through NINJA (delt_t= 0.2s beginning at t=0)

Jun 9 1997 11:07:02:340AM970605011Steve Wukitchdud hybrid dud
Jun 9 1997 11:07:24:550AM970605012Steve Wukitchhybrid-only test
Jun 9 1997 11:07:51:480AM970605013Steve Wukitchplasma no He3 puff
Jun 9 1997 11:12:15:860AM970605014Steve Wukitchplasma He3 puff from NINJA (delt_t=0.2 at t=0); P_rf = 0.8 MW
Jun 9 1997 11:14:58:810AM970605015Steve Wukitchplasma FMIT #3 and #4 ran simultaneously; ramped power to 0.6 MW
Jun 9 1997 11:17:45:030AM970605016Steve Wukitchplasma disrupted @0.4 sec; preceeded by an unexplained density rise (density sharkfin)
Jun 9 1997 11:32:33:090AM970605017Steve Wukitchplasma disrupted @0.97 sec; ramped P_rf to 1.5 MW
Jun 9 1997 11:33:19:580AM970605018Steve Wukitchplasma disrupted @0.97 sec; ramped P_rf to 1.6 MW
Jun 9 1997 11:37:11:590AM970605019Steve Wukitchdud increased He3 (del_t = 0.3 sec at t=0)
"magnet resistance fault" (only EF2 and EFC supplies fired)
Jun 9 1997 11:38:21:620AM970605020Steve Wukitchfiz increased outer gap from 0.4 cm to 0.8 cm
Jun 9 1997 11:38:42:500AM970605021Steve Wukitchfiz
Jun 9 1997 11:40:00:620AM970605022Steve Wukitchdud Hybrid dud; put pi/2 phase delay in FMIT#4
Jun 9 1997 11:40:56:470AM970605023Steve Wukitchplasma disrupt @1.15 P_rf = 1 MW total
Jun 9 1997 11:42:01:530AM970605024Steve Wukitchplasma removed pi/2 delay and put in pi phase delay in FMIT#4; P_rf=0.8 MW
Jun 9 1997 11:44:02:560AM970605026Steve Wukitchplasma P_rf=1.0 MW (FMIT#4 only)
Jun 9 1997 11:44:41:250AM970605027Steve Wukitchplasma ramped to P_rf=2.0 MW for 0.05 sec
Jun 9 1997 11:46:30:740AM970605027Steve Wukitchplasma FMIT#4 faulted
Jun 9 1997 11:47:20:920AM970605028Steve Wukitchfiz
Jun 9 1997 11:47:56:370AM970605029Steve Wukitchplasma disrupt @0.37 sec
Jun 9 1997 11:48:09:400AM970605030Steve Wukitchfiz
Jun 9 1997 11:48:55:390AM970605031Steve Wukitchplasma FMIT#4 crowbar; cannot re-initialize
Jun 9 1997 11:49:13:160AM970605032Steve Wukitchplasma no RF

Physics Operator Comments
Jun 5 1997 07:28:25:530AMSteve WolfeColdstart ok at 07:25:28.22
Jun 5 1997 07:31:20:270AMSteve WolfeRun plan for 970605:

Overnight ECDC in D2.

Engineering setup as on 970604047; TF under hybrid control.

Gas setup - hybrid enable the following valves
fill K-side with 20 PSI of D2
fill B-top with 5 PSI of D2
Fill but do not enable: B-side-lower with 4 PSI of Ar
B-side-upper should still have He3 - DO NOT PURGE!

Note: there is a possible problem with the B-side-upper gas board. J. Goetz
has sent e-mail to Willy Burke about this. It may be necessary to run some
test cycles with someone in the cell before the start of the run to check this
out.

Enable ECE, PCX, TCX, VUV, Moly gate valves if their vacuums are acceptable.

The run will start out with MP 170A (startup) and MP171A (RF conditioning).
We may also try to use the cryopump prototype (MP 160).

Session leader Takase has the option of starting an experiment outlined in OPS
bulletin.
Jun 5 1997 08:27:37:910AM970605001Steve WolfeSet up a .5 sec pulse for Willy to check the gas board.

Willy is going to just swap out the board for a spare.
Put back the 970604047 shot in PCS

Forgot to move the fizzle detector. NO output
Try again
Jun 5 1997 08:34:30:010AM970605002Steve WolfeStill checking on gas board, fizzle detector moved to 1.5sec

Willy is going to just swap out the board for a spare.
Put back the 970604047 shot in PCS
Access bypassed for Mike and Sergei in Power room.

OK - 9V signal on B-side upper. No gas observed on ratiomatic or RGA though.

Jun 5 1997 08:46:07:220AM970605003Steve WolfeLengthen pulse on PG2 to 100msec to see if it will open there.
Still no gas in the machine.

Jun 5 1997 09:18:20:880AM970605004Steve WolfeBurke and Blip are in the cell to look at signals at the valve, to see if they are getting all the
through. Still a 100msec pulse @.5sec

Didn't see it.

Jun 5 1997 09:19:10:460AM970605005Steve WolfeBurke and Blip are in the cell to look at signals at the valve, to see if they are getting all the
through. Make it a 500msec pulse @.5sec

They saw that.
Try a 1sec pulse onto the valve next.

Jun 5 1997 10:20:53:370AM970605005Steve WolfeI've drawn a 1sec pulse; there is a question whether the hand-valve is open.

It turns out the piezo is dead. 5.6ohms (should be 1Mohm or so)
Punt the B-side-upper. We'll use the NINJA for He3 if at all.

Jun 5 1997 11:06:45:450AM970605006Steve WolfeShot 6: Go for plasma
Re-load, for about the fifth time, 970604047
RF has solved an oscillation problem on transmitter #4.
Blip is getting set up for NINJA.

Cryo has a problem with the transfer line; no cryo today.
There is LN2 in the cryopump now. It should be warming up.
We may get cryo later; the problem was the pump on the xfer line.

plasma ; lots of hards?
bd at 5.6msec, CII =.006.
hard xrays (eq. neut rate=1.5e14)!
Nice density, current.
Rf claims to be 1MW (on #3), #4 100kW early, retrying late.

Jun 5 1997 11:22:21:180AM970605007Steve WolfeShot 7: Move seg1 PG3 earlier
Enable Argon
Move RF pulses later in shot to get to where we have 4T.
Still runaways.
disr at 1.12.
Got RF for both pulses.
Jun 5 1997 11:37:59:710AM970605008Steve WolfeShot 8: Raise PG4 from 22 to 25msec
IC_ef4 from -1325 to -1315.
TF to -116 move tf ramp earlier by 100msec
plasma, runaways not obvious on tv. runs to 1.45.

some hesitation in early current, not terrible.
No hards.
RF looking better.
Jun 5 1997 11:58:59:510AM970605009Steve WolfeShot 9: TF from -116 to -117 (he wants 4.3, not 4.25)
Blip is doing a test pulse on NINJA before shot, while Mike does something in pwr room.
NINJA at .3 for .1;
Move RCUR to sit at .675 from .5sec on, instead of ramping out.

plasma to 1.43
RF from #3, #4 still dropping out early.

Jun 5 1997 12:16:21:620PM970605010Steve WolfeShot 10: NINJA pulse length to .200 and .1 sec earlier.
plasma to 1.4sec
RF still working on getting #4 to coexist with #3
Jun 5 1997 12:41:57:090PM970605011Steve WolfeShot 11: NINJA pulse length to .200 and .1 sec earlier.
Change ZXL program from flat at -.018 to ramp down to -.023 from 0.65 sec to 1.2sec
Move end point on TF ramp from .45 to .35 to try to get the field down by .5sec

dud. POwer supplies look strange.
hybrid signals look bad.

The physAout signals look like there are holes in them.
The problem seems to be on the Wavegen outputs.
It has lots of chops in it.
Jun 5 1997 12:56:14:220PM970605012Steve WolfeShot 12:
Taking a test shot on the hybrid. #279
Wavegen now looks ok.

Take an open circuit test shot.
Pout looks fine. I have no idea what could cause it to glitch like that.
Jun 5 1997 01:16:38:100PM970605013Steve WolfeShot 13:
try again: NINJA pulse length to .200 and .1 sec earlier.
only through one capilary this time.
Change ZXL program from flat at -.018 to ramp down to -.023 from 0.65 sec to 1.2sec
Move end point on TF ramp from .45 to .35 to try to get the field down by .5sec

plasma. 1.46 sec. No glitches on hybrid.
RF got .6MW on #4.
May need more ramp on ZXL, but it did what I asked.
Strike is on probe 6-7, flatter, but too high.
May need to run RXL in, but not next shot.
Cell access to turn on cryo; also RSG,Dimitri,Rejean have things to do.


Jun 5 1997 01:33:20:250PM970605014Steve WolfeShot 14:
Cryo is cooling
Everything else should be the same, except NINJA should go with both barrells
base=7.2e-7 and dropping

plasma, to 1.43
Rf get .8MW from something
Cryo not yet below 39K (where the CERNOX detectors work)




Jun 5 1997 01:43:52:870PM970605015Steve WolfeShot 15: no changes

plasma, 1.43 sec
RF supposedly runs together.





Jun 5 1997 02:03:34:030PM970605016Steve WolfeShot 16: no changes
Cell access before shot; Frank wants to look at xfer line.
RF is tracking down a possible arc

plasma - short. disr at .4, near oh1 crossover
looks like an early sharkfin(?) like yesterday.
OH1 crowbarred again.





Jun 5 1997 02:15:06:330PM970605017Steve WolfeShot 17: no changes, see if it comes back
base=1.2e-6

plasma to .97sec
divot at .6sec, goes boom at .97
RF is ramping up to 1.5MW
Big injection; Brian denies responsibility





Jun 5 1997 02:26:15:360PM970605018Steve WolfeShot 18: Brian will not fire at the late time
No other changes.

plasma disr at .97 again
antenna is glowing incandescant when power is on,


Jun 5 1997 02:33:26:910PM970605019Steve WolfeShot 19: Change RCUR from .675 to .673 to increase gap a bit.
cryo not cooling; still a problem with the transfer line.

dud - hardly any supplies: the dreaded magnet resistance fault
Jun 5 1997 02:44:23:320PM970605020Steve WolfeShot 20: Retry (same as 19)
Change RCUR from .675 to .673 to increase gap a bit.
cryo not cooling; still a problem with the transfer line.

fizzle. late breakdown 12msec
Jun 5 1997 02:54:07:550PM970605021Steve WolfeShot 21: br0 from .006 to .0065
Still waiting to see if the RCUR change helps

fizzle bd at 15msec!
null looks like I went the right way; plasma doesn't agree
Jun 5 1997 03:05:16:020PM970605022Steve WolfeShot 22: No change, see if it comes back on it's own.
No supplies - dud

No hybrid demands? NO wavegen signals.
This is the second wavegen screwup today. It did this last week.

Test shot 280 runs ok.
Jun 5 1997 03:14:05:400PM970605023Steve WolfeShot 23: No change, see if it comes back on it's own.
plasma - disrupted at 1.15 sec
bd at 6msec, nice early current rise.
RF power lower, around 1MW.
outer gap now around 7mm, larger before the disruption.
Jun 5 1997 03:27:07:210PM970605024Steve WolfeShot 24: No changes from my end
plasma - made it through to ramp-down (1.48sec)

Under 1MW on the RF. They are worried because they thought they changed the phase and it
didn't change.

bd was a little later, 6.8msec. It may be drifting away again.
Jun 5 1997 03:41:50:650PM970605025Steve WolfeShot 25: No changes from my end

plasma, 1.46 sec
Only 1 RF pulse (1MW); #4 went, #3 tripped
Jun 5 1997 03:51:05:340PM970605026Steve WolfeShot 26: Extend RCUR flat from 1.2sec to 1.5sec to try to extend rampdown
Next shot I may delay the RCUR offset switch from 1.4 sec to 1.6 just to see what happens.

plasma - same length 1.44sec
rf gets to 2MW
bd back at 6.3msec
Jun 5 1997 03:59:44:470PM970605027Steve WolfeShot 27: Move jump in RCUR offset (8000 to 6000) from 1.4 sec to 1.6 sec
Blip wants me to move RXL in to try to lower the strike.

plasma, 1.49sec
RF got 1MW. transmitter #4 faulted before the shot.
Jun 5 1997 04:20:35:870PM970605028Steve WolfeShot 28: Hold ZXL near constant in rampdown, instead of ramping up
Cryo has punted for the day.

fizzle. late bd (12msec)
null looks no worse than before, but there is a negative Br thrash.
Cell access for Dmitri, while I decide whether to leave it or tweak.
Jun 5 1997 04:35:07:020PM970605029Steve WolfeShot 29: shot 28 had a very early gas chop (1msec and again at 8msec)
I'm going to delay the pg3 program to 8msec.

short disruption @.370, turned around at .3
Injections
bd was back at 6msec

Just go again.
Jun 5 1997 04:42:26:680PM970605030Steve WolfeShot 30: No changes
base=1.8e-6
fizzle, made it to 40kA. a bouncer.
It's visible on ECE? Was it going to runaway?
Just go again.
Jun 5 1997 04:49:48:580PM970605031Steve WolfeShot 31: No changes
base=1.1e-6

plasma to 1.46 sec
Note that the last rampdown change was to ZXL, and didn't do any good.
It looks like a small shark fin.
Rf made it to 2MW, but only briefly
camac errors on some engineering voltage traces
Jun 5 1997 04:55:24:070PM970605032Steve WolfeShot 32: NO RF, (trans #4 has crowbarred)
turn off b-side lower to see if it affects the rampdown.

plasma- same length.

Engineering Operator Comments
ShotTimeTypeStatusComment
108:23:53:020AMTestBadGAS TEST ONLY
208:30:00:130AMTestOkGAS TEST
308:41:08:790AMTestOkGAS TEST
409:06:47:770AMTestOkGAS TEST
509:13:37:700AMTestBadgas test
610:57:41:170AMTestOk
711:13:16:380AMTestOk
811:33:11:430AMTestOk
911:51:45:330AMPlasmaOk
1012:11:47:470PMPlasmaOk
1112:24:09:390PMTestOk
1212:51:24:100PMTestOk
1312:58:22:450PMPlasmaOk
1401:25:52:930PMPlasmaOk
1501:38:37:940PMPlasmaOk
1601:55:25:930PMPlasmaOk
1702:05:04:440PMPlasmaOk
1802:18:03:100PMPlasmaOk
1902:31:28:810PMPlasmaOk
2002:39:46:650PMPlasmaOk
2102:49:14:370PMPlasmaOk
2202:57:56:280PMPlasmaBadhybrid fault
2303:07:22:640PMPlasmaOk
2403:22:42:920PMPlasmaOk
2503:31:29:500PMPlasmaOk
2603:44:31:370PMPlasmaOk
2703:54:18:770PMPlasmaOk
2804:14:14:590PMPlasmaOk
2904:29:12:720PMPlasmaOk
3004:37:02:840PMPlasmaOk
3104:43:49:240PMPlasmaOk
3204:53:27:270PMPlasmaOk