Alcator C-Mod Run 941117 Information

Miniproposals

Miniproposal:

Date Filed:

Title:

First Author:

Session Leader: Steve Horne (shots 1-32)

Operators
Session leader(s):	Steve Horne
Physics operator(s):	Ian Hutchinson,Steve Wolfe
Engineering operator(s):	Joe Daigle,Vinny Bertolino

Engineering Operator Run Comment
first plasmas?

Session Leader Plans

Physics Operators Plans

Session Leader Summaries

Entered: Jul 7 2004 03:49:11:273PM

Author: To Be Determined

Run 941117; Check out hybrid control & First plasma attempt;
Horne, Wolfe, (Hutch), Daigle, Bertolino

First attempt at plasma.
The first shot was a plasma attempt; we expected something not to work
but the precharge looked identical to an old fiducial shot;
this constituted the hybrid checkout.
After some tweaks and fiddles, got a breakdown on shot 4,
first plasma on shot 10.
We're running with more positive BZ than we used to,
based on the current set of functional flux loops.
Whether the BZ is actually different is an open
question. Otherwise things look nominal.

The shots that went (10,13,16,20,24,31) were all at 8.e-6 fill
and had very similar programming. The last 3 were identically
programmed, and differed from the first 3 by a .0005 tesla tweak to br.
The predictor recalculation after shot 11 should not
have affected the current rise, so programming for shot 10 was probably
very close to the others. I suspect the real determinant
of fizzle or plasma is impurity levels on the RGA.

I think we were all surprised at how well things went.
Power supplies, control system, PCS, computers don't
seem to have noticed the break. We got 32 shots.
Improved cooling + fizzle detector + generally
high reliability of all systems were responsible.

Plasmas are filthy, of course.

For tomorrow -- don't count on the PCS model being right
because Josh is testing some cosmetic fixes to PCS.
Reload the shot you want.

Steve Horne.

=======Run Begins ======

1.3e-5 gas
inverts at .25
Newly recalculated predictors for segment 1

shot 1. Fiducial shot, 940624001.

shot 2. Gas programming restored from shot 940624001
Chopper demand still not right

shot 3 Changed chopper programming. Don't totally understand
what was in the shot.
Also make ef4 100 A more negative, from -1025 to -1125.
Better null, but no flash.

4. turn off chopper feedback by changing controller on time to +1 sec.
Adjust voltage programming to 0.
30 A more negative on ef4

Flash!!

5. Turn chopper back on (wire 3 controller)
Reduce zcur wire 3 offset from 1000 to 0.
Flash!

6. Br from +2.5e-3 to +3.e-3
Flash.
br to 4.e-3
zcur wire 2 offset to 0.

7 flash
scatterplot shows bz TOO POSITIVE.
EF4 FROM -1155 TO -1180
br=4.e-3

8 flash
Put bz back to -1155

9. flash
Drop fill to 1.1e-5

10. PLASMA!
Change chopper V to taper it in. The plasma was sick, but the chopper
actually killed it.

11. This shot is a repeat
Long delay before this shot due to init hang, then alternator speed problem.

Recalculate all fluxihh (again). Ian believe the ian tree we used
has dutch elm disease. We're back to the tree we used last summer.
flash, but no current rise. Just hit it again.
Haven't loaded the changes yet.
Change to chopper V did the right thing -- efc I tapers in.

12 Fizzle. Drop the fill to 9.e-6

13 PLASMA.

Reduce initial puff from 45 to 35 V.
Raise fill to 1.e-5
Load all the new predictors.

14. fault of some sort during init -- back to recool
Fizzle.
Drop the fill back to .9 e -5.

15 fizzle
Drop br offset from 5.e-3 to 4.5e-3.

16 PLASMA
RCUR OFFSETS TO ZERO from 10000.
invert times moved late -- same as standard fiducial

17 fizzle. bz vs t is wrong, probably
due to rcur offset tweak. Take rcur offset to 5000.

18 fizzle. Hit it again.

19 fizzle.
put rcur offset back to 10000.

20 PLASMA 370 ka.
Change rcur programming early, to try to prevent the outward
bang.

21 fizzle.
No change for next shot.

22 fizzle
Mutter an obscure incantation and reload shot 20.

23 Fizzle.
Last shots show z-meter spike quite high, but decreasing.
Fill Gas to 8.e-6.

24 Plasma. Best yet. 370 msec, 250 or so kA. zmeter spike < .1

25 Dud. Operating theory is that shot 24 changed wall conditions, so
Raise fill to 1.0e-5.

26 fizzle.

27 Now drop back to 8.e-6.
Fizzle, zmeter spike at .11

28 ef4 from -1155 to -1140
Fizzle. Breakdown at about 10. msec, from 11.
zmeter spike .10

29 ef4 from -1140 to -1125
Fizzle. Breakdown at 7.5, zmeter at .06.
This is near where we used to be.

30 ef4 from -1125 to -1110.
Fizzle,, breakdown at 5 msec.

31 Mutter the same incantation, reload 24.
PLASMA

32 reload 30.
oh2 currents 1KA more negative. This is an attempt to
fix what's perceived as a problem with gradients.
fill 1.e-5, based of shots 24-26
Fizzle.

Run ends.

Physics Operator Summaries

Session Leader Comments

Physics Operator Comments

Nov 17 1994 08:31:02:480AM Steve Wolfe Created to new copies of MHD_STATIC shots=1016,1017 to deal with the
failed F16 loop. The set up for these is as follows:

1016: INcludes all Full loops except F16; includes the decants.

1017: Includes all full loops except F12,F16,F17; includes the decants.

Set up the \ANALYSIS::RECON_VAC:STATIC_SHOT to point to 1017, which
seems to work better than 1016.

Note: An IDL pro to make new static shots is in
USER9:[wolfe.idl.cmod]fix_recon_vac.pro

Nov 17 1994 09:27:41:500AM 941117001 Steve Wolfe Fill to 1.3e-5

Try for everything.
Dud.

According to RECON_VAC there is about -5mT of Br, +8mT of Bz
No gas puff. It was set up from yesterday's terst instead of ther fiducial.

Ian reports funniness on MFLUX reconstruction.

Nov 17 1994 09:43:59:950AM 941117002 Steve Wolfe Try again.

Set BR0 offset to +.0025 from -.0025
Reprogram gas puff from 940624001

No change to chopper, which had a problem last time.

Dud. Br0 is better, Bz0 claims to be +12 mT.

Nov 17 1994 09:57:01:480AM 941117003 Steve Wolfe 941117003:
Try again. EF4 100a more negative.
SFH fiddled with chopper programming

dud.
Bz now is about +3mT, Br = -1.9mT. according to vacuum.
MFLUX says we're getting closer, but has a possible problem with partials

Nov 17 1994 10:12:26:920AM 941117004 Steve Wolfe 941117004:
Try again. EF4 30a more negative.
SFH turned off chopper feedback and turned V programming to 0

got a flash !!!
A tiny tiny amount of current.
Bz0 says +3mT, Br0 says -2mT
MFLUX says there is no null, but close.

Chopper worked "right" this time.

Nov 17 1994 10:33:43:740AM 941117005 Steve Wolfe 941117005:
Turned chopper back down and reduced ZCUR offset on 3 to 0.
No other changes. See if it repeats.

Flash on TV and on Halpha, Z-meter. Looks the same, breakdown is at
12msec.

Nov 17 1994 10:55:56:680AM 941117006 Steve Wolfe 941117006:
Change BR0 offset from .0025 to .0030

Another flash.
Earlier breakdown, 7msec. Br looks better.

Nov 17 1994 11:18:13:020AM 941117007 Steve Wolfe 941117007:
Change BR0 offset from .003 to .0040
Change ZCUR2 offset from 10000 to 0.

Change TV filter to Halpha (from none).

Still flashes.
SCSI camac failedagain. Tom claims it was the Zmeterdecoder.

Nov 17 1994 11:39:59:250AM 941117008 Steve Wolfe 941117008:
EF4 from -1155 to -1180amp

Flashed again.
Later breakdown (12msec)
Ian thinks we've gone too far on Bz. (I agree).

Nov 17 1994 11:51:49:490AM 941117009 Steve Wolfe 941117009:
EF4 back to -1155 from -1180amp
Br0 to .005
There is lots of agitation to lower the gas. It will be ignored for
this shot.

Still flashing, looks wimpier on the TV.
Broke down earlier, but no burnout on Zmeter.
Ian says radial field looks better on MFLUX reconstruction.

Nov 17 1994 12:07:20:580PM 941117010 Steve Wolfe 941117010:

Drop gas to 1.1e-5.
No other changes

Plasma -- Over 100msec of plasma, 190kA.

Nov 17 1994 12:49:41:040PM 941117011 Steve Wolfe 941117011:

Change chopper to taper in.
No other changes, it probably will choke anyway.
Indications are previous shot went down and in.

Ian says the IAN$data tree we copied in last night is broken.
He will copy in the old version (ignoring F17) and we need to recalc
all FLUXIHH predictors (for next shot, not this one).

Alternator fault in CHECK. Had to back out.

Weak flash, No current rise.
Looks similar, Br a bit more positive.

Nov 17 1994 01:01:20:480PM 941117012 Steve Wolfe 941117012:

No changes - hit it again.

Almost identical to 11.
Fields look the same.

Nov 17 1994 01:10:28:380PM 941117013 Steve Wolfe 941117013:

Drop the fill to 0.9e-6 !!

Another 200kA plasma.
Starts down at 100msec, snuffs at 160msec
We may be over-gassing with the puff.

Nov 17 1994 01:35:00:790PM 941117014 Steve Wolfe 941117014:

Drop early gas puff by 15volts
Load re-calculated FLUXIHH predictors
Raise fill to 1.e-5

Little flash. NO current.

Nov 17 1994 01:42:59:000PM 941117015 Steve Wolfe 941117015:

Drop fill back to 0.9e-5 and try again.

Flash - shorter and dimmer.

Nov 17 1994 02:00:11:110PM 941117016 Steve Wolfe 941117016:

Make Br0 more negative by 0.5mTesla (to 4.5e-3)

Got it back. Lasted till invert time at 250 msec, but was dying of
disruptions and radiation.

Xray centroid claims to be outside, but ok up down.

Nov 17 1994 02:09:18:220PM 941117017 Steve Wolfe 941117017:
Move invert times out to 1.5 sec
Change RCUR offset from 10000. to 0.

Flashed. Light lasted almost 100msec, but no current
Bz never rose. It looks like we overdid the RCUR offset; it thinks its
always inside.

Nov 17 1994 02:24:04:250PM 941117018 Steve Wolfe 941117018:
Change RCUR offset to 5000. from 0.

Little flash. Shorter than 17.
RCUR still thinks its inside.

Nov 17 1994 02:28:53:700PM 941117019 Steve Wolfe 941117019:
No changes, just hit it again.

Looks the same.

Nov 17 1994 02:48:37:030PM 941117020 Steve Wolfe 941117020:
Put the RCUR offset back to 10000.

Got it back. Dies at 200msec but got up to 350-400kA.

Position is outside, but better than 16.

Nov 17 1994 02:58:16:070PM 941117021 Steve Wolfe 941117021:

Change RCUR program early, to move plasma further in.

Small flash. Negligible current.

Nov 17 1994 03:04:21:390PM 941117022 Steve Wolfe 941117022:

Repeat. See if it goes this time.

Flash. Very similar, maybe shorter. Z-meter light may be lower

Nov 17 1994 03:20:34:720PM 941117023 Steve Wolfe 941117023:

Re-load shot 20.

Short flash. Looks worse.

Nov 17 1994 03:32:47:370PM 941117024 Steve Wolfe 941117024:

Drop the gas to 8e-6 (and pray)

Got it back, looked longer on the screen.
Lasted till 360msec. Current peaks at 110msec, 275ka.
Then disrupts continuously.

Nov 17 1994 03:39:53:170PM 941117025 Steve Wolfe 941117025:

Repeat of 24

No flash? dud.

Nov 17 1994 03:50:26:760PM 941117026 Steve Wolfe 941117026:

Raise fill back to 1.0e-5

Fizzle.

Nov 17 1994 04:00:37:090PM 941117027 Steve Wolfe 941117027:
Drop the fill to 8e-6 again.

Another fizzle.

Nov 17 1994 04:10:52:810PM 941117028 Steve Wolfe 941117028:
Make EF4 15 amps more positive.

Fizzle. breakdown is a hair earlier. breakdown spike is lower.

Nov 17 1994 04:25:49:340PM 941117029 Steve Wolfe 941117029:
Make EF4 15 amps more positive, again to -1125.

Fizzle. broke down earlier 7.5msec

Nov 17 1994 04:36:02:080PM 941117030 Steve Wolfe 941117030:
Make EF4 15 amps more positive, again to -1110.

Fizzle - earlier breakdown 5msec.

Nov 17 1994 04:48:45:830PM 941117031 Steve Wolfe 941117031:
Reload 24

Got it back. 400kA. 300msec.

Nov 17 1994 05:06:04:380PM 941117032 Steve Wolfe 941117032:
Reload 30. Increase OH2 current program by -1kA. (to -22.7kA)
The idea is to make the gradient more positive.

Raise fill to 1.0e-5

Fizzle. Breakdown at 4.7msec

Engineering Operator Comments

Shot Time Type Status Comment

1 09:03:50:910AM Plasma Ok no faults all supplies

2 09:32:46:480AM Plasma Ok no faults

3 09:45:44:520AM Plasma Ok no faults

4 09:58:41:310AM Plasma Ok no faults

5 10:28:55:420AM Plasma Ok no faults

6 10:50:14:660AM Plasma Ok no faults

7 11:06:13:470AM Plasma Ok no faults

8 11:26:44:360AM Plasma Ok no faults

9 11:44:40:060AM Plasma Ok no faults

10 11:56:54:660AM Plasma Ok no faults

11 12:11:37:690PM Plasma Ok No faults

12 12:51:28:700PM Plasma Ok good shot (no faults)

13 01:03:31:200PM Plasma Ok No faults

14 01:23:19:600PM Plasma Ok NO faults

15 01:36:44:270PM Plasma Ok No faults.

16 01:48:59:320PM Plasma Ok no faults

17 02:03:24:960PM Plasma Ok No faults.

18 02:12:27:740PM Plasma Ok Power supply No faults.

19 02:24:47:110PM Plasma Ok No faults.

20 02:36:05:440PM Plasma Ok No Faults

21 02:50:19:210PM Test Ok No faults.

22 03:00:29:690PM Test Ok No faults.

23 03:11:24:190PM Plasma Ok No faults

24 03:23:16:830PM Plasma Ok No faults

25 03:35:13:690PM Plasma Ok No faults

26 03:45:58:970PM Plasma Ok No faults

27 03:56:18:190PM Plasma Ok No faults

28 04:06:31:050PM Plasma Ok No faults

29 04:17:01:320PM Plasma Ok No faults

30 04:29:42:970PM Plasma Ok No faults

31 04:44:27:830PM Plasma Ok No faults.

32 04:55:25:780PM Plasma Ok NO FAULTS.

Physics Operator Comments
Nov 17 1994 08:31:02:480AM		Steve Wolfe	Created to new copies of MHD_STATIC shots=1016,1017 to deal with the failed F16 loop. The set up for these is as follows: 1016: INcludes all Full loops except F16; includes the decants. 1017: Includes all full loops except F12,F16,F17; includes the decants. Set up the \ANALYSIS::RECON_VAC:STATIC_SHOT to point to 1017, which seems to work better than 1016. Note: An IDL pro to make new static shots is in USER9:[wolfe.idl.cmod]fix_recon_vac.pro
Nov 17 1994 09:27:41:500AM	941117001	Steve Wolfe	Fill to 1.3e-5 Try for everything. Dud. According to RECON_VAC there is about -5mT of Br, +8mT of Bz No gas puff. It was set up from yesterday's terst instead of ther fiducial. Ian reports funniness on MFLUX reconstruction.
Nov 17 1994 09:43:59:950AM	941117002	Steve Wolfe	Try again. Set BR0 offset to +.0025 from -.0025 Reprogram gas puff from 940624001 No change to chopper, which had a problem last time. Dud. Br0 is better, Bz0 claims to be +12 mT.
Nov 17 1994 09:57:01:480AM	941117003	Steve Wolfe	941117003: Try again. EF4 100a more negative. SFH fiddled with chopper programming dud. Bz now is about +3mT, Br = -1.9mT. according to vacuum. MFLUX says we're getting closer, but has a possible problem with partials
Nov 17 1994 10:12:26:920AM	941117004	Steve Wolfe	941117004: Try again. EF4 30a more negative. SFH turned off chopper feedback and turned V programming to 0 got a flash !!! A tiny tiny amount of current. Bz0 says +3mT, Br0 says -2mT MFLUX says there is no null, but close. Chopper worked "right" this time.
Nov 17 1994 10:33:43:740AM	941117005	Steve Wolfe	941117005: Turned chopper back down and reduced ZCUR offset on 3 to 0. No other changes. See if it repeats. Flash on TV and on Halpha, Z-meter. Looks the same, breakdown is at 12msec.
Nov 17 1994 10:55:56:680AM	941117006	Steve Wolfe	941117006: Change BR0 offset from .0025 to .0030 Another flash. Earlier breakdown, 7msec. Br looks better.
Nov 17 1994 11:18:13:020AM	941117007	Steve Wolfe	941117007: Change BR0 offset from .003 to .0040 Change ZCUR2 offset from 10000 to 0. Change TV filter to Halpha (from none). Still flashes. SCSI camac failedagain. Tom claims it was the Zmeterdecoder.
Nov 17 1994 11:39:59:250AM	941117008	Steve Wolfe	941117008: EF4 from -1155 to -1180amp Flashed again. Later breakdown (12msec) Ian thinks we've gone too far on Bz. (I agree).
Nov 17 1994 11:51:49:490AM	941117009	Steve Wolfe	941117009: EF4 back to -1155 from -1180amp Br0 to .005 There is lots of agitation to lower the gas. It will be ignored for this shot. Still flashing, looks wimpier on the TV. Broke down earlier, but no burnout on Zmeter. Ian says radial field looks better on MFLUX reconstruction.
Nov 17 1994 12:07:20:580PM	941117010	Steve Wolfe	941117010: Drop gas to 1.1e-5. No other changes Plasma -- Over 100msec of plasma, 190kA.
Nov 17 1994 12:49:41:040PM	941117011	Steve Wolfe	941117011: Change chopper to taper in. No other changes, it probably will choke anyway. Indications are previous shot went down and in. Ian says the IAN$data tree we copied in last night is broken. He will copy in the old version (ignoring F17) and we need to recalc all FLUXIHH predictors (for next shot, not this one). Alternator fault in CHECK. Had to back out. Weak flash, No current rise. Looks similar, Br a bit more positive.
Nov 17 1994 01:01:20:480PM	941117012	Steve Wolfe	941117012: No changes - hit it again. Almost identical to 11. Fields look the same.
Nov 17 1994 01:10:28:380PM	941117013	Steve Wolfe	941117013: Drop the fill to 0.9e-6 !! Another 200kA plasma. Starts down at 100msec, snuffs at 160msec We may be over-gassing with the puff.
Nov 17 1994 01:35:00:790PM	941117014	Steve Wolfe	941117014: Drop early gas puff by 15volts Load re-calculated FLUXIHH predictors Raise fill to 1.e-5 Little flash. NO current.
Nov 17 1994 01:42:59:000PM	941117015	Steve Wolfe	941117015: Drop fill back to 0.9e-5 and try again. Flash - shorter and dimmer.
Nov 17 1994 02:00:11:110PM	941117016	Steve Wolfe	941117016: Make Br0 more negative by 0.5mTesla (to 4.5e-3) Got it back. Lasted till invert time at 250 msec, but was dying of disruptions and radiation. Xray centroid claims to be outside, but ok up down.
Nov 17 1994 02:09:18:220PM	941117017	Steve Wolfe	941117017: Move invert times out to 1.5 sec Change RCUR offset from 10000. to 0. Flashed. Light lasted almost 100msec, but no current Bz never rose. It looks like we overdid the RCUR offset; it thinks its always inside.
Nov 17 1994 02:24:04:250PM	941117018	Steve Wolfe	941117018: Change RCUR offset to 5000. from 0. Little flash. Shorter than 17. RCUR still thinks its inside.
Nov 17 1994 02:28:53:700PM	941117019	Steve Wolfe	941117019: No changes, just hit it again. Looks the same.
Nov 17 1994 02:48:37:030PM	941117020	Steve Wolfe	941117020: Put the RCUR offset back to 10000. Got it back. Dies at 200msec but got up to 350-400kA. Position is outside, but better than 16.
Nov 17 1994 02:58:16:070PM	941117021	Steve Wolfe	941117021: Change RCUR program early, to move plasma further in. Small flash. Negligible current.
Nov 17 1994 03:04:21:390PM	941117022	Steve Wolfe	941117022: Repeat. See if it goes this time. Flash. Very similar, maybe shorter. Z-meter light may be lower
Nov 17 1994 03:20:34:720PM	941117023	Steve Wolfe	941117023: Re-load shot 20. Short flash. Looks worse.
Nov 17 1994 03:32:47:370PM	941117024	Steve Wolfe	941117024: Drop the gas to 8e-6 (and pray) Got it back, looked longer on the screen. Lasted till 360msec. Current peaks at 110msec, 275ka. Then disrupts continuously.
Nov 17 1994 03:39:53:170PM	941117025	Steve Wolfe	941117025: Repeat of 24 No flash? dud.
Nov 17 1994 03:50:26:760PM	941117026	Steve Wolfe	941117026: Raise fill back to 1.0e-5 Fizzle.
Nov 17 1994 04:00:37:090PM	941117027	Steve Wolfe	941117027: Drop the fill to 8e-6 again. Another fizzle.
Nov 17 1994 04:10:52:810PM	941117028	Steve Wolfe	941117028: Make EF4 15 amps more positive. Fizzle. breakdown is a hair earlier. breakdown spike is lower.
Nov 17 1994 04:25:49:340PM	941117029	Steve Wolfe	941117029: Make EF4 15 amps more positive, again to -1125. Fizzle. broke down earlier 7.5msec
Nov 17 1994 04:36:02:080PM	941117030	Steve Wolfe	941117030: Make EF4 15 amps more positive, again to -1110. Fizzle - earlier breakdown 5msec.
Nov 17 1994 04:48:45:830PM	941117031	Steve Wolfe	941117031: Reload 24 Got it back. 400kA. 300msec.
Nov 17 1994 05:06:04:380PM	941117032	Steve Wolfe	941117032: Reload 30. Increase OH2 current program by -1kA. (to -22.7kA) The idea is to make the gradient more positive. Raise fill to 1.0e-5 Fizzle. Breakdown at 4.7msec

Engineering Operator Comments
Shot	Time	Type	Status	Comment
1	09:03:50:910AM	Plasma	Ok	no faults all supplies
2	09:32:46:480AM	Plasma	Ok	no faults
3	09:45:44:520AM	Plasma	Ok	no faults
4	09:58:41:310AM	Plasma	Ok	no faults
5	10:28:55:420AM	Plasma	Ok	no faults
6	10:50:14:660AM	Plasma	Ok	no faults
7	11:06:13:470AM	Plasma	Ok	no faults
8	11:26:44:360AM	Plasma	Ok	no faults
9	11:44:40:060AM	Plasma	Ok	no faults
10	11:56:54:660AM	Plasma	Ok	no faults
11	12:11:37:690PM	Plasma	Ok	No faults
12	12:51:28:700PM	Plasma	Ok	good shot (no faults)
13	01:03:31:200PM	Plasma	Ok	No faults
14	01:23:19:600PM	Plasma	Ok	NO faults
15	01:36:44:270PM	Plasma	Ok	No faults.
16	01:48:59:320PM	Plasma	Ok	no faults
17	02:03:24:960PM	Plasma	Ok	No faults.
18	02:12:27:740PM	Plasma	Ok	Power supply No faults.
19	02:24:47:110PM	Plasma	Ok	No faults.
20	02:36:05:440PM	Plasma	Ok	No Faults
21	02:50:19:210PM	Test	Ok	No faults.
22	03:00:29:690PM	Test	Ok	No faults.
23	03:11:24:190PM	Plasma	Ok	No faults
24	03:23:16:830PM	Plasma	Ok	No faults
25	03:35:13:690PM	Plasma	Ok	No faults
26	03:45:58:970PM	Plasma	Ok	No faults
27	03:56:18:190PM	Plasma	Ok	No faults
28	04:06:31:050PM	Plasma	Ok	No faults
29	04:17:01:320PM	Plasma	Ok	No faults
30	04:29:42:970PM	Plasma	Ok	No faults
31	04:44:27:830PM	Plasma	Ok	No faults.
32	04:55:25:780PM	Plasma	Ok	NO FAULTS.