Alcator C-Mod Run 991102 Information

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Miniproposals
Miniproposal:206
Date Filed:12/31/1998
Title:Restart Operation: January 1999
First Author:Steve Wolfe
Session Leader:Steve Wolfe (shots 1-30)

Operators
Session leader(s):Steve Wolfe
Physics operator(s):John Goetz
Engineering operator(s):Gary Dekow,Bill Cochran,Frank Silva

Engineering Operator Run Comment
Reverse start up/Wolfe/Silva

Session Leader Plans

Physics Operators Plans

Session Leader Summaries
Entered: Jul 7 2004 03:49:22:257PM
Author: To Be Determined
Run Summary for 991102

MP#206 startup (reverse-field)
SL: wolfe
PO: Goetz
EO: Silva,Cochran

Plan:
-----
The purpose of this run is to establish operation with reversed (positive)
field and current, and carry out discharge development for the reverse-field
physics runs later this week.

The TF and PF busswork was reversed on Saturday. The HYBRID tree has been
modified to reflect the new configuration (smw-991030).

Operation will begin with a series of PLC power system tests to verify the
configuration changes. HYBRID demands will be monitored during the PLC shots
to verify the Hybrid/PCS changes.

Plasma operation will start with a reversed current shot based on 991029022, a
good 800kA shot from last Friday. Some tweaking will presumably be required to
get a good startup, and to adjust offsets for RCUR and perhaps other
wires. Check gaps for RF.

If the startup goes smoothly, we may try increasing the current to 1.0 and
1.2MA, to allow the RF group to check the coupling in preparation for the run
on Wednesday.

For the upper x-point run on Thursday, Ian wants to do triangularity scans
like those on 990922. We'll start from a static point (RXL=0) based on
990922006, then try to implement the sweep.

Results:
--------

We succeeded only in the first of the goals, getting a plasma with reversed
field. The startup is far from robust, and we only got three plasmas that
reached flattop (#24-26). Those shots however lasted to 2sec (longest ever),
when they were taken out by power supply inversion.

RF turned on on shot 26, and got close to a MW using D&E together. Both
transmitters ran without faulting at the 0.4-0.5MW level. Unfortunately, we
lost the plasma after #26, so they were unable to increase the power.

CLEARIN required substantial re-programming to avoid running with zero
gaps. Shot 24 was limited on both sides for most of the long shot, and had an
elongation of only 1.3. Shot 25 was better, with elongation of 1.5, and #26
was close to nominal with eout=1.6. The program waveform changed from shot to
shot from -.01 to +.01 to +0.015. I suspect we actually should be using an
offset in CLEARIN of magnitude 5000 : 10000, but this was not done. A dummy
CLEARIN with offset of 10000 was loaded on wire 9 with no gain for shot 26,
for comparison.

ZCUR also had to be adjusted, from -0.015 to -.005 in order to get an EFIT
ZMAXIS of -.008m.

The RCUR offsets in segment 2 were changed from +8000,+5000 to
-8000,-5000. These were not checked in detail. The Segment 1 RCUR offset was
changed from 5500 to negative values in the range -5500 : -10000. It seems to
matter a lot, but no robust solution was found. All the successful startups
had bad hesitations.

The upper null segments set up for development of Ian's run on Thursday are
still sitting in segments 3 and 4, as described in the logbook, but were not
tried. The RCUR offsets and CLEARIN and ZCUR program waveforms should
presumably be modified as was done to segment 2.

All the power systems ran well today, except for an unexplained OH2L failure
on shot 22. Irby was monitoring the TF resistances, and gave us permission to
put the delay on the TF fizzle detector back to 0.1 sec after shot 23. This
helped a good deal on cooling after fizzles. The tc's used to indicate central
column cooling seemed to have changed, such that we were not getting below
about -176 no matter how long we cooled. One possibility is that the reference
point junction is off-temp.










Physics Operator Summaries
Entered: Jul 7 2004 04:37:09:897PM
Author: To Be Determined
Physics operator summary for 9911-2

EO: Silva & Cochran & Dekow
PO: Wolfe & Goetz
SL: Wolfe

Run 991102 was in support of MP 206 -- Startup (with reversed field)
The purpose of this run is to establish operation with reversed (positive)
field and current, and carry out discharge development for the reverse-field
physics runs later this week. The TF and PF busswork was reversed on Saturday,
October 30. The HYBRID tree has been modified to reflect the new configuration
(SMW-991030). Operation will begin with a series of PLC power system tests to
verify the configuration changes. HYBRID demands will be monitored during the
PLC shots to verify the Hybrid/PCS changes.

Plasma operation will start with a reversed current shot based on 991029022, a
good 800kA shot from last Friday. Some tweaking will presumably be required to
get a good startup, and to adjust offsets for RCUR and perhaps other
wires. Check gaps for RF. If the startup goes smoothly, we may try increasing
the current to 1.0 and 1.2MA, to allow the RF group to check the coupling in
preparation for the run on Wednesday. For the upper x-point run on Thursday,
November 4, triangularity scans like those on 990922 need to be done. We'll
start from a static point (RXL=0) based on 990922006, then try to implement
the sweep.

The first thirteen shots today were used as tests to determine if the
changeover in the magnet bus was done correctly. The run began with a plasma
attempt on shot 14. This was, luckily, a fizzle with positive radial field
and 20mT of vertical field. The OH1 was producing too much current and the
demand was lowered. Also, the EF1s were lowered 200A in an attempt to get
the curvature of the field straightened out. The offset in the RCUR controller
in segment 1 was twiddled about to try and find the best number to use.
Eventually, an offset of between -5500 and -8000 produced plasmas. It was
also necessary to increase the EF4 current to 1425A in order to get the
vertical field correct.

After all of this, three plasmas were produced. Each had a serious hesitation
in the current rise. However, each plasma lasted longer than 2s. The first
plasma produced indicated that there was also an offset problem with CLEARIN.
This manifested itself in a plasma that was limited on both the inner and outer
limiters. The drawn waveform was changed by 2.5cm to obtain gaps similar to
those of "normal" field. The vertical position, ZCUR, also had an offset, and
a change of +1cm brought ZCUR back to its nominal -0.6cm position.

These three plasmas were followed by four fizzles to end the run. These four
appeared to be lost vertically (down) as indicated by the MFLUX z calculation.
Why this vertical excursion appeared remains unexplained. The last shot was
a reload of a plasma shot and it too fizzled with this vertical excursion.

Engineering, computing, and diagnostics today:
The OH2L supply pulled after the switch closing @ -0.7sec resulting
in a dud. All else appeared to be o.k.

Scorecard: 30 shots = 3 plasmas + 13 fizzles + 1 duds + 13 tests

Shot summary for Run 991020

Steve Wolfe does a bunch of pre-run setup work
PCS Setup:
-----------
LOAD_FROM 991029022 (acknowledge config mismatch)
IMPORT_SEG #3 from 990922006 segment 2
IMPORT_SEG #4 from 990922006 segment 2 (same as #3)

Segment #1: All_p's - flip all IC_*, IP
All V's - flip everything but pulse gas
BR0 offset is already 0.0!
RCUR offset is 5500; leave it for now
Change title to "Reverse field startup"
Segment #2:
All P's: flip EF2byEF4, IC_EF4, Ip
All V's: flip everything but pg valves
RCUR offsets are 8000,5000. Leave them for now.
Change title to "800kA reverse-field lower null"
Segment #3: All P's: flip EF2byEF4, IC_EF4,Ip;
flip ZCUR for upper null;
set RXL,RXU waveforms to zero
interchange ZXL and ZXU
All V's: flip all voltages except pg valves
RCUR offsets are 8000,5000. Leave them for now, change as
indicated by seg 2 results.
CLEARIN: set keyword ZXA=.394 and CALL ALG | Apply | OK factor
Controller: zxa=.394 | call | OK | OK timeconst.
STRKSPI: keywords RSOUT=.685,ZSOUT=.60,ZXA=.394 | Call Alg
waveform set to zero
Pgain to 5 starting at .3sec
Controller: zxa=.394,RSOUT=.685,ZSOUT=.60,

ALL=['PSI0','RCUR','ZCUR','CLEARIN','STRKPSI','RXL','ZXL','RXU']
Call | set common rate to 9.0
Factor to .0001 (was .0002)
RXL: Load gains from RXU (seg 4, wire 7)
ZXL: Load gains from ZXU (seg 4, wire 8)
RXU: Load gains from RXL (seg 4, wire 5)
ZXU: Load gains from ZXL (seg 4, wire 6), set to 0.5 after
0.3sec
Change title to reverse-field upper null
Segment 4: Import segment from PCS$SCRATCH, shot -1, seg#3
For RXL, RXU load wave from 990922006 RXU, RXL
(\PCS::TOP.SEG_02:P_05,\PCS::TOP.SEG_02:P_07).
RXL exceeds wavegen limit; reduce factor from 4e-5 to 3.6e-5.
Change title to "Reverse field triangularity scan"

Build All - No errors or warnings
Save As 991102999 (just in case)
Load/Clean - put it in the model, ready to go.

coldstart hybrid - everything loaded; all matrices respond

The plasma INIT scope in the CMOD$MODELS:[HYBRID.SCOPES] area
has an offset in the plasma current used in the calculation
of R and z. This offset has the wrong sign for this bus
configuration.

Shot change result
____ _____ ______

1 EF2U 2kA PLC test shot EF2U current is positive (as intended)
EF2U voltage is also ok; Hybrid is
calling for +voltage, then negative

2 EF2L 2Ka PLC test shot looks ok

3 EFC 1Ka test shot. negative on EFC_L

4 TF test (50KA, PLC control) o.k.; 50KA positive

5 EF4 test shot; "forward" o.k.; positive current, 1250A in each

6 EF4 test shot; "negative" o.k.; negative current

7 EF3 test shot air flow problem in the air switch

8 EF3 test shot o.k.; -1750A

9 EF1U test shot o.k.; 2kA positive

10 EF1L test shot o.k.; 2kA positive

11 OH1 test shot o.k.; 10kA positive

12 OH2U test shot o.k.; 10kA positive

13 OH2L test shot o.k.; 10kA positive

14 try for plasma; EF4 limit fizzle; b.d. @ .027s!!!; Bz = -.02T @
only set to 8.5kA t=0; Br(0)=.001; OH1 has about 1kA
more current than last week

15 IC_OH1=19kA (was 20kA) fizzle; b.d. @ .006s; Bz = -.012T; Br=0
field curvature is wrong

16 IC_OH1=18.5kA; IC_EF1s=5900A fizzle; b.d. @ .005s; Bz=-.005T; Br=0
(was 6000A) field curvature is wrong

17 IC_OH1=19kA; IC_EF4=1380A fizzle; b.d. @ .0045; Bz=-.006; Br=0;
(was 1280A) field curvature is wrong

18 IC_EF1s to 5800A; flip the fizzle; b.d. @ .005; Bz=-.008; Br=+.001
sign on the RCUR offset because vert. field is straight; RCUR error
the RCUR error is ~14000 is now ~4000

19 IC_EF4=1410A; RCUR offset to fizzle; b.d. @ .006; Bz=-.006; Br=+.001
-10000 in segment 1 RCUR error is now -1500

20 IC_EF4=1440A; RCUR offset to 0 fizzle; b.d. @ .007; Bz=-.005; Br=+.001
RCUR error ~8000

21 IC_EF4=1425A; BR_0 offset = dud; OH2L pulls out @ -0.7
-.001; PG4 = 22ms (was 18ms)

22 try again fizzle; b.d. @ .0055; Bz turns around
after breakdown; second plasma forms
@ .045s

23 RCUR offset = -2750 fizzle; b.d. @ .006; Bz falls as Ip
rises; three plasmas this time

24 RCUR offset = -5500 plasma until 2sec; b.d. @ .006; bad
hesitation; both gaps near zero; large
offset on CLEARIN

25 RCUR offset = -7000; draw plasma until 2sec; b.d. @ .005; bad
CLEARIN to +.01 (was -.01) hesitation; kappa=1.5; some gaps

26 RCUR offset=-8000; CLEARIN plasma until 2sec; b.d.@.0055; very bad
out to .015; ZCUR up 1cm hesitation; gaps and position o.k.

27 PG4=20ms; CLEARIN=.01 @ .37S fizzle; b.d. @ .0055; 40kA; current
rise too fast for Bz

28 RCUR offset = -9000 fizzle; b.d. @ .006; 40kA

29 PG4=22ms; BR_0=0 fizzle; weaker

30 reload 991102026; CLEARIN=.01 fizzle; seems to be moving down
@ 0.37s

Session Leader Comments
Nov 2 1999 10:05:37:530AM991102007Steve WolfeShot 7: EF3 test. Didn't go.
Nov 2 1999 10:16:23:483AM991102008Steve WolfeShot 8: EF3 test. (try again, it had a Rectifier air-flow fault last time?!)
OK, -1700A
Nov 2 1999 10:19:47:903AM991102009Steve WolfeShot 9: EF1U test - positive current, 2Ka
Nov 2 1999 10:26:19:030AM991102010Steve WolfeShot 10: EF1L test/ should be same polarity.
OK.
Nov 2 1999 10:35:11:797AM991102011Steve WolfeShot 11: OH1 test.
Electrons tree back on, to check on ECE and TCI.
positive 10KA - ok


Next shot, oh2u.
Nov 2 1999 10:41:27:090AM991102012Steve WolfeShot 12: oh2u test - ok, 10kA positive, switch closes normally

Nov 2 1999 10:49:58:983AM991102013Steve WolfeShot 13: oh2l test - looks good.

Next shot: Try for plasma.

Nov 2 1999 11:21:04:763AM991102014Steve WolfeShot 14: Try for plasma.

Note: Bill points out that the EF4 was reset to 8.5ka on 990922,
not at 10kA, as indicated in Ian's logbook entry. Therefore, we
will use 8.5ka and hope for the best (it won't matter until we get
to the x-point sweep, anyway).

Fizzle detector is set to take out the TF early, for this first full current shot.

Fizzle. Bz0 is very negative (-20mT). Breakdown is at 30msec.
OH1 is at 20.6kA, EF4 is at 1250A; setpoints are 20.0 and 1280,
and OH1 is normally around 19.7kA.

Next shot: Decrease IC_OH1 program.

Nov 2 1999 11:40:52:810AM991102015Steve WolfeShot 15: OH1 current program down by 1kA.
TF fd delay to 1500msec
anoter fizzle.
Bz is still -10mT. bd at 7msec.
Br0 ~0.
Has strong negative curvature on MFLUX plots.

Next shot: try another 500A off of IC_OH1, 100A off of the EF1's.

Nov 2 1999 11:59:52:153AM991102016Steve WolfeShot 16: try another 500A off of IC_OH1, 100A off of the EF1's.
On further reflection, I think we should have used the EF4 instead of OH1.
fizzle- bd at 5msec, index is still bad (worse).

Next shot- put back OH1, put 100A on EF4.
Note: In Ian's INIT scope, change the sign of the Ip offset in RCUR and ZCUR panels.
Nov 2 1999 12:20:33:013PM991102017Steve WolfeShot 17: put OH1 back to 19kA, put +100A on EF4, leave EF1's at 5900
fizzle. bd at 4.7msec
curvature still too negative, but better.

Next shot: Reverse sign of RCUR offsets (seg 1 and 2), and
take another 100A off of EF1's (to 5800A)

Nov 2 1999 12:46:02:403PM991102018Steve WolfeShot 18: Reverse sign of RCUR offsets (seg 1 and 2), and
take another 100A off of EF1's (to 5800A)

fizzle. Curvature is better, Bz takes off negative after 10ms,
probably too much so.

Next shot: EF4 more positive by 30A,
seg 1 RCUR offset from -5500 => -10000
Nov 2 1999 01:12:42:560PM991102019Steve WolfeShot 19: EF4 more positive by 30A, seg 1 RCUR offset from -5500 => -10000
And another fizzle!
RCUR error is now negative, but it doesn't help; maybe worse than previous.

Nov 2 1999 02:00:12:217PM991102020Steve WolfeShot 20: Seg1 RCUR offset to 0. from -10000; +30A more on EF4
There is a delay while the cooling is looked at.

After 45 minutes, another fizzle.
Bz evolution certainly changed.
Breakdown looks even dimmer than before.
Nov 2 1999 02:11:38:437PM991102021Steve WolfeShot 21: Back off 15A on EF4 and raise gas. BR0 from 0 to -.001
Running out of ideas (and daylight).

Dud. OH2L crowbars at -.7sec

Nov 2 1999 02:41:33:170PM991102022Steve WolfeShot 22: Repeat of 21
Back off 15A on EF4 and raise gas. BR0 from 0 to -.001

fizzle, but it gets to 50KA before it dies.
Some runaways, and can see it on ECE and XUV
Nov 2 1999 03:06:57:217PM991102023Steve WolfeShot 23: RCUR offset to -2700 in seg1.
tf fizzle delay back to 100msec (from 1500), to see if it will help the cooling

Gets to 80kA, eventually, but it takes several bumps on the way.
The Bz evolution is very non-monotonic.

Next shot: RCUR offset back to -5500.
Keep going that way until it stops getting better?
Nov 2 1999 03:30:11:623PM991102024Steve WolfeShot 24: RCUR offset back to -5500.
Keep going that way until it stops getting better?

Plasma runs to 2sec! Front of the room TV didn't show up.
Still has a bad hesitation
Both gaps go to zero for most of the shot.
Elongation=1.3
CLEARIN seems to have a big offset
Nov 2 1999 03:50:06:873PM991102025Steve WolfeShot 25: Set CLEARIN to +.01 (was -.01).
Attack hesitation by another RCUR offset tweak, to -7000 in seg1

plasma to 2sec again
Elongation is 1.5, and the gaps are about 0.5cm
Zaxis is about 1.5cm low.
Some hards early.

Next shot: Raise ZCUR by 1cm, Increase CLEARIN by .005, RCUR offset to -8000
Put a dummy CLEARIN wire on wire 9, with 0 gains and 10000. offset
RF will try to fire.
Nov 2 1999 04:10:34:390PM991102026Steve WolfeShot 26: Raise ZCUR by 1cm, Increase CLEARIN by .005, RCUR offset to -8000
Put a dummy CLEARIN wire on wire 9, with 0 gains and 10000. offset
RF will try to fire.

Plasma to 2sec.
Hesitation is different, slower rise, then a dip
D&E at 0.4MW each.
Left gap at 1.5 and dropping, right gap drops to 0 at 0.5, but flattops at 0.75cm
No hards.

Next shot: Move CLEARIN positive more quickly, lower the fill, turn on the Argon
Nov 2 1999 04:23:08:090PM991102027Steve WolfeShot 27: Move CLEARIN positive more quickly, lower the fill, turn on the Argon
fizzle. current rise is faster, Bz doesn't change.

Next shot: try RCUR offset to -9000
Nov 2 1999 04:35:44:640PM991102028Steve WolfeShot 28:try RCUR offset to -9000
Move CLEARIN positive more quickly, lower the fill, turn on the Argon

Another fizzle.

Next shot: Br0 back to 0 from -.001; raise the fill again.
Nov 2 1999 04:46:25:903PM991102029Steve WolfeShot 29:Br0 back to 0 from -.001; raise the fill again
try RCUR offset to -9000
Move CLEARIN positive more quickly, lower the fill, turn on the Argon

fizzle. Go back to 26, with the CLEARIN adjusted.

Physics Operator Comments
Nov 1 1999 12:16:58:450PMSteve WolfeSetting up PCS for tomorrow's reversed-field run:

LOAD_FROM 991029022 (acknowledge config mismatch)
IMPORT_SEG #3 from 990922006 segment 2
IMPORT_SEG #4 from 990922006 segment 2 (same as #3)

Segment #1: All_p's - flip all IC_*, IP
All V's - flip everything but pulse gas
BR0 offset is already 0.0!
RCUR offset is 5500; leave it for now
Change title to "Reverse field startup"

Segment #2:
All P's: flip EF2byEF4, IC_EF4, Ip
All V's: flip everything but pg valves
RCUR offsets are 8000,5000. Leave them for now.
Change title to "800kA reverse-field lower null"

Segment #3: All P's: flip EF2byEF4, IC_EF4,Ip;
flip ZCUR for upper null;
set RXL,RXU waveforms to zero
interchange ZXL and ZXU
All V's: flip all voltages except pg valves
RCUR offsets are 8000,5000. Leave them for now, change as indicated by seg 2 results.
CLEARIN: set keyword ZXA=.394 and CALL ALG | Apply | OK factor
Controller: zxa=.394 | call | OK | OK timeconst.
STRKSPI: keywords RSOUT=.685,ZSOUT=.60,ZXA=.394 | Call Alg
waveform set to zero
Pgain to 5 starting at .3sec
Controller: zxa=.394,RSOUT=.685,ZSOUT=.60,
ALL=['PSI0','RCUR','ZCUR','CLEARIN','STRKPSI','RXL','ZXL','RXU']
Call | set common rate to 9.0
Factor to .0001 (was .0002)
RXL: Load gains from RXU (seg 4, wire 7)
ZXL: Load gains from ZXU (seg 4, wire 8)
RXU: Load gains from RXL (seg 4, wire 5)
ZXU: Load gains from ZXL (seg 4, wire 6), set to 0.5 after 0.3sec
Change title to reverse-field upper null
Segment 4: Import segment from PCS$SCRATCH, shot -1, seg#3
Didn't pick up the title change, but seems to have the waveforms?
For RXL, RXU load wave from 990922006 RXU, RXL (\PCS::TOP.SEG_02:P_05,
\PCS::TOP.SEG_02:P_07). RXL exceeds wavegen limit; reduce factor from 4e-5 to 3.6e-5.
Change title to "Reverse field triangularity scan"

BUild All
Save As 991102999
Load/Clean
Nov 2 1999 07:24:04:717AMSteve WolfeColdstart at 07:23
Logfile ok, all matrices respond.
Nov 2 1999 09:54:02:437AMJohn GoetzRun Plan for Tuesday, 991102
----------------------------

Engineering setup:
------------------

Engineering Setup for Tuesday, 991102: Reverse field startup and development

Run will BEGIN at 09:00 and END at 17:00

Setup power supplies from shot 991029022, except
INCREASE EF4 CURRENT LIMIT TO 10kA.

Note: FIZZLE DETECTOR OFF TIME at 1.7 s

2 hours ECDC in D2 prior to the run, stopping 1 hour before run.

Gas setup - fill B-top with 6 psi of D2 Hybrid enabled
fill B-side lower with 1 psi of Ar Hybrid DISABLED
fill B-side upper with 10 psi of H2 Hybrid DISABLED
fill C-side with 30 psi of D2 Hybrid enabled
leave J-bottom as is (pumped out)

Assuming no vacuum problems, enable ECE and VUV

Nov 2 1999 09:54:46:840AMJohn GoetzRun Plan for Tuesday, 991102
----------------------------

Engineering setup:
------------------

Physics Run Plan
________________
MP#206 Startup (with reversed field)

The purpose of this run is to establish operation with reversed (positive)
field and current, and carry out discharge development for the reverse-field
physics runs later this week.

The TF and PF busswork was reversed on Saturday. The HYBRID tree has been
modified to reflect the new configuration (smw-991030).

Operation will begin with a series of PLC power system tests to verify the
configuration changes. HYBRID demands will be monitored during the PLC shots
to verify the Hybrid/PCS changes.

Plasma operation will start with a reversed current shot based on 991029022, a
good 800kA shot from last Friday. Some tweaking will presumably be required to
get a good startup, and to adjust offsets for RCUR and perhaps other
wires. Check gaps for RF.

If the startup goes smoothly, we may try increasing the current to 1.0 and
1.2MA, to allow the RF group to check the coupling in preparation for the run
on Wednesday.

For the upper x-point run on Thursday, Ian wants to do triangularity scans
like those on 990922. We'll start from a static point (RXL=0) based on
990922006, then try to implement the sweep.
Nov 2 1999 09:07:37:327AM991102001Steve WolfeShot 1: EF2U 2Ka PLC test shot.
EF2U current is positive (as intended).
EF2U voltage is also ok
Hybrid is calling for +voltage, then negative
Nov 2 1999 09:13:15:077AM991102002Steve WolfeShot 2: EF2L 2Ka PLC test shot.
looks ok
Nov 2 1999 09:17:59:327AM991102003Steve WolfeShot 3: EFC 1Ka test shot.
Well, it's the right sign (negative on EFC_L).
Nov 2 1999 09:24:01:030AM991102004Steve WolfeShot 4: TF test (50KA, PLC control)
50KA positive, ok.
Nov 2 1999 09:52:34:387AM991102005Steve WolfeShot 5: EF4 PLC test, "forward" (should be positive)
OK, current is positive, 1250A in each.
I'm not seeing the supply voltage trace.
STORE ACTION, and several inputs of \ENGINEERING::PS_CAMAC.EF4:TR16_1
were turned off in the pulse file. Too quick on the trigger.

Next shot, reverse bridge EF4.
Nov 2 1999 09:56:45:950AM991102006Steve WolfeShot 6: EF4 PLC test, "reverse" (should be negative)
OK, negative current, and the voltage is now there.

Goetz is here and taking over as PHYSOP. I'll close my PCS now
Nov 2 1999 10:01:44:327AM991102006John GoetzShot 006
EF4 test shot
800 A; looks o.k.
Nov 2 1999 10:04:24:890AM991102007John GoetzShot 007
EF3 test shot
air flow problem; no pulse
Nov 2 1999 10:16:26:060AM991102008John GoetzShot 008
EF3 test shot
looks o.k.; -1750A
Nov 2 1999 10:21:41:327AM991102009John GoetzShot 009
EF1U 2kA test shot
looks o.k., 2kA positive
Nov 2 1999 10:26:06:450AM991102010John GoetzShot 010
EF1L 2kA test shot
looks o.k., 2kA positive
Nov 2 1999 10:34:11:857AM991102011John GoetzShot 011
OH1 test shot
10kA positive
Nov 2 1999 10:41:24:653AM991102012John GoetzShot 012
OH2U test shot
10kA positive
Nov 2 1999 10:48:55:280AM991102013John GoetzShot 013
OH2L test shot
10kA positive
Nov 2 1999 11:20:09:967AM991102014John GoetzShot 014
try for plasma
EF4 PLC limit set to 8.5kA only

Results
fizzle
breakdown @ .027s!!!
Bz = -.02T @ t=0; Br(0)=.001
OH1 has about 1kA more current than an equivalent shot from last week
Nov 2 1999 11:39:05:937AM991102015John GoetzShot 015
draw IC_OH1 to 19kA (was 20kA)

Results
fizzle
breakdown @ .006s
Bz = -.012T @ breakdown but it is going more negative after breakdown; Br(0)~0mT
field curvature is in the wrong direction
Nov 2 1999 11:54:49:733AM991102016John GoetzShot 016
draw IC_OH1 to 18.5kA
draw IC_EF1s to 5900A (was 6000A)
Results
fizzle
breakdown @ .005s
Bz = -.005T @ breakdown but it is going more negative after breakdown; Br(0)~0mT at breakdown
field curvature is in the wrong direction
Nov 2 1999 12:22:03:357PM991102017John GoetzShot 017
draw IC_OH1 to 19kA
draw IC_EF4 to 1380A (was 1280A)
it was noted that in the INIT scope, there is an offset removed from the plasma current in the calculation
of R and z. This offset is off by a sign now that the currents have been reversed.

Results
fizzle
breakdown @ .0045s
Bz = -.006T @ breakdown but it is going more negative after breakdown; Br(0)~0mT at breakdown
field curvature is in the wrong direction
Nov 2 1999 12:41:38:153PM991102018John GoetzShot 018
draw IC_EF1s to 5800A
the RCUR error is ~14000 before breakdown so change the sign on the RCUR offset (from 5500 to -5500 in segment 1 and
from 8000 to -8000 in segment 2)

Results
fizzle
breakdown @ .005s
Bz = -.008T @ breakdown and goes the right direction after breakdown; Br(0)~0mT at breakdown
field curvature is straight now
RCUR error is down to ~4000
Nov 2 1999 01:21:16:840PM991102019John GoetzShot 019
draw IC_EF4 to 1410A
keep going on the RCUR offset - change to -10000 in segment 1

Results
fizzle
breakdown @ .006s
Bz = -.006T and Br(0)~0mT at breakdown
RCUR error is down to -1500
it is difficult to tell where this plasma is, but the thought is that it is getting snuffed on the inside
Nov 2 1999 01:58:04:000PM991102020John GoetzShot 020
draw IC_EF4 to 1440A
change the RCUR offset to 0 in segment 1

Results
fizzle; very weak; hardly any visible light signals
breakdown @ .007s
Bz = -.005T but not rising very quickly; Br(0)~+1mT at breakdown
RCUR error is 8000

Nov 2 1999 02:19:01:513PM991102021John GoetzShot 021
draw IC_EF4 to 1425A
change pre-puff to 22ms from 18ms
Br_0 offset = -.001

Results
dud - OH2L power supply pulls out at -0.7s - probably something to do with the switch closing
Nov 2 1999 02:42:26:107PM991102022John GoetzShot 022
draw IC_EF4 to 1425A
change pre-puff to 22ms from 18ms
Br_0 offset = -.001

Results
fizzle; breakdown @ .0055; makes 40kA
Bz turns around after the breakdown
second plasma forms over the whole chamber at about 45ms
Nov 2 1999 03:07:31:980PM991102023John GoetzShot 023
RCUR offset = -2750

Results
fizzle; breakdown @ .006; only 30kA
Bz turns around as the current rises which shouldn't be
three plasmas this time - @ .006, .02, and .034
Nov 2 1999 03:32:03:733PM991102024John GoetzShot 024
RCUR offset = -5500

Results
plasma - ran until 2sec; breakdown @ .006; bad hesitation
outer gap = 0; inner gap = 0.8cm->0; kappa = 1.3
there appears to be a large offset on CLEARIN
Nov 2 1999 03:51:03:967PM991102025John GoetzShot 025
RCUR offset = -7000
draw CLEARIN to +.01 (was -.01) to try and take care of the offset

Results
plasma - ran until 2sec; breakdown @ .006; bad hesitation
outer gap = 0.6; inner gap = 1cm->0.5; kappa = 1.5
ZCUR = -1.3cm
Nov 2 1999 04:03:42:047PM991102026John GoetzShot 026
RCUR offset = -8000
draw CLEARIN to +.015
ZCUR up 1cm to -.007
load spare CLEARIN onto wire 9 - turn off gains and put 10000 offset in for diagnostic purposes

Results
plasma - ran until 2sec; breakdown @ .0055; really bad hesitation!
outer gap = 0.75; inner gap = 1.2cm->0.9; kappa = 1.6
ZCUR = -0.6cm
Nov 2 1999 04:23:46:700PM991102027John GoetzShot 027
PG4 = 20ms (was 23ms) to try and help out on the current rise
CLEARIN = .01 @ .37s to try and get rid of OH1 crossover bump

Results
fizzle; breakdown @ .0055
current rises to 40kA too quickly for the Bz
Nov 2 1999 04:35:35:450PM991102028John GoetzShot 028
RCUR offset = -9000 to try and speed up Bz

Results
fizzle; breakdown @ .006
current rises to 40kA
Nov 2 1999 04:47:03:640PM991102029John GoetzShot 029
PG4 = 22ms (was 20ms)
BR_0 offset = 0 (was -.001)

Results
fizzle; very weak
Nov 2 1999 05:04:26:090PM991102030John GoetzShot 030
reload 991102026
CLEARIN = .01 @ .37sec

Results
fizzle; this one appears to be moving down

Engineering Operator Comments
ShotTimeTypeStatusComment
108:59:42:513AMTestOkef2u only
209:08:13:090AMTestOkef2lower test only
309:15:21:297AMTestOkefc chopper test only
409:22:22:327AMTestOkTF test only
509:38:15:810AMTestOkef4 forward test
609:52:57:153AMTestOkef4reverse test
710:01:15:263AMTestOkef3 air flow fault , no pulse
810:11:30:920AMTestOkef3 test
910:17:55:903AMTestOkef1upper test
1010:24:43:263AMTestOkEF1 Lower test ok
1110:31:21:810AMTestOkoh1 test
1210:39:21:280AMTestOkoh2upper test
1310:46:52:140AMTestOkoh2lower test
1411:09:52:217AMPlasmaOkno faults/late fizzel
1511:28:31:030AMPlasmaOkno faults fizzel
1611:47:32:653AMPlasmaOkno faults/fizzel
1712:10:50:060PMPlasmaOkno faults/fizzell
1812:32:14:153PMPlasmaOk(null)
1901:00:56:890PMPlasmaOk(null)
2001:46:40:357PMPlasmaOkfizzle
2102:07:33:873PMPlasmaBadoh2lower comm flt.
2202:31:29:733PMPlasmaOkfizzle
2302:54:36:217PMPlasmaOkfizzle
2403:09:14:560PMPlasmaOkPlasma
2503:32:01:450PMPlasmaOkplasma
2603:51:51:763PMPlasmaOkplasma
2704:11:40:467PMPlasmaOkfizzle
2804:26:11:750PMPlasmaOkfizzle
2904:41:40:950PMPlasmaOkfizzle
3004:55:50:547PMPlasmaOkfizzle