Alcator C-Mod Run 1030509 Information

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Miniproposals
Miniproposal:
Date Filed:
Title:
First Author:
Session Leader:Yijun Lin (shots 1-18)

Operators
Session leader(s):Yijun Lin
Physics operator(s):Jim Irby
Engineering operator(s):Bill Byford,Bill Parkin,Bill Cochran

Engineering Operator Run Comment
Purpose: RF Conditioning and Debug Bus Instrumentation/Noise Problem.

Session Leader Plans

Physics Operators Plans

Session Leader Summaries

Physics Operator Summaries
Entered: Jul 7 2004 04:37:17:740PM
Author: To Be Determined
Physop Summary for Run 1030509 --- RF conditioning

EO: Cochran, Byford, Parkin
PO: Irby
SL: Lin

We spent a lot of the day trying to debug the noise that is getting
into the bus Rogowskis and shunts and eventually causing disruptions.
We began the run with tests of the EF3, EF4, and TF supplies. The
supplies showed no indication of a problem. On shot 04 we tried for
plasma and got a very nice startup. Everything went well until shot
12 when the problem ocurred again. After checking all the breakers
except EF3, we did a no power cycle test on 13, followed by resumed
plasma operation on shot 14.

On a more positive note, we were getting up to 4.5 MW of rf power into
the machine today, and Earl got a few pellets launched. Also should note
that startup was 100% today.


tests 04
plasmas 14

cycles 18

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1030509001 irby PHYSICS_OPERATOR May 9 2003 8:27:34:463AM
. . . . . . . . . . . . . . . . . . . .
Start with EF3 pulse

Got it... nothing seen on shunts
----------------------------------------------------------------------------
1030509002 irby PHYSICS_OPERATOR May 9 2003 8:47:34:233AM
. . . . . . . . . . . . . . . . . . . .
EF4 reverse bridge first

got it --- nothing seen
----------------------------------------------------------------------------
1030509003 irby PHYSICS_OPERATOR May 9 2003 9:16:28:240AM
. . . . . . . . . . . . . . . . . . . .
EF4 Forward bridge

got it --- nothing seen
----------------------------------------------------------------------------
1030509004 irby PHYSICS_OPERATOR May 9 2003 9:53:04:466AM
. . . . . . . . . . . . . . . . . . . .
150 kA TF under PLC control

got it --- nothing seen
----------------------------------------------------------------------------
1030509005 irby PHYSICS_OPERATOR May 9 2003 10:26:58:293AM
. . . . . . . . . . . . . . . . . . . .
gas from 20 to 25 ms. pressure was .05 vs .065 mTorr yesterday

plasma --- nice startup --- no noise

kept rf off, also next shot...
----------------------------------------------------------------------------
1030509006 irby PHYSICS_OPERATOR May 9 2003 10:42:57:950AM
. . . . . . . . . . . . . . . . . . . .
repeat of shot 5

good shot --- no noise, no rf...


----------------------------------------------------------------------------
1030509007 irby PHYSICS_OPERATOR May 9 2003 11:36:37:673AM
. . . . . . . . . . . . . . . . . . . .
long pause as we await the TF scanner to be repaired-------------------

gas from 25 to 24 ms

rf this shot

good plasma --- some rf heating

no noise on shunts.

TF scanner still didn't work....


Time (ms): 0 5 10 25
----------------------------------------
Ip (kA): -4.8266 -12.9732 -27.6262 -120.8333
dIp/dt (kA/ms): -0.9121 -2.3469 -4.1379 -7.3156
pressure (mTorr): 0.0640 0.0626 0.0633 0.0547
Bz0 (mT): -2.5100 -0.1889 2.6939 23.1796
Br0 (mT): -0.5731 -0.8940 -1.1725 -0.6168

Pressure down more than expected, but seems to work okay...
----------------------------------------------------------------------------
1030509008 irby PHYSICS_OPERATOR May 9 2003 12:02:58:786PM
. . . . . . . . . . . . . . . . . . . .
Argon from 25 to 50 ms (John claims this is okay in L mode)

plasma --- some j-port coming on-line

nice rampdown

no noise, no scanner, Joe heads to the cell...
----------------------------------------------------------------------------
1030509009 irby PHYSICS_OPERATOR May 9 2003 12:40:40:920PM
. . . . . . . . . . . . . . . . . . . .
repeat after another long TF scanner pause

plasma

TF scanner is back

----------------------------------------------------------------------------
1030509010 irby PHYSICS_OPERATOR May 9 2003 12:50:52:696PM
. . . . . . . . . . . . . . . . . . . .
repeat

plasma --- 4.5 MW of rf !

no noise
----------------------------------------------------------------------------
1030509011 irby PHYSICS_OPERATOR May 9 2003 1:10:02:586PM
. . . . . . . . . . . . . . . . . . . .
gas from 24 to 23 ms

plasma

H/(H+D) around 12% --- came up with rf as usual

approaching 5 MW of rf, Wp about 80 kJ max

no TF scanner
----------------------------------------------------------------------------
1030509012 irby PHYSICS_OPERATOR May 9 2003 2:26:23:160PM
. . . . . . . . . . . . . . . . . . . .
Noise problem again

plasma shutdown by 80 ms

going out to look at all the beaker contacts
----------------------------------------------------------------------------
1030509013 Cycle test to check scanner
----------------------------------------------------------------------------
1030509014 irby PHYSICS_OPERATOR May 9 2003 3:51:40:186PM
. . . . . . . . . . . . . . . . . . . .
All 13.8 breakers except ef3 have been inspected --- nothing was seen
If we have the problem again we will take time to look at ef3

Plasma but no rf

no noise

----------------------------------------------------------------------------
1030509015 irby PHYSICS_OPERATOR May 9 2003 3:52:32:656PM
. . . . . . . . . . . . . . . . . . . .
repeat

plasma --- rf and li pellet
----------------------------------------------------------------------------
1030509016 irby PHYSICS_OPERATOR May 9 2003 4:21:06:443PM
. . . . . . . . . . . . . . . . . . . .
repeat

nice plasma, just a little rf




----------------------------------------------------------------------------
1030509017 irby PHYSICS_OPERATOR May 9 2003 4:40:26:160PM
. . . . . . . . . . . . . . . . . . . .
repeat

plasma

TF scanner looks good
----------------------------------------------------------------------------
1030509018 irby PHYSICS_OPERATOR May 9 2003 5:03:31:586PM
. . . . . . . . . . . . . . . . . . . .
plasma, but lost late because noise glitches did in Rogowskis
again.

got some rf, but no pellet.
----------------------------------------------------------------------------
1030509xxx irby PHYSICS_OPERATOR May 9 2003 8:17:55:790AM
. . . . . . . . . . . . . . . . . . . .
We will begin the run early today and try to debug noise on shunts, rogs, that is
large enough to affect the Hybrid and cause disruptions (pickup on Rogowskis).

Will start with full length EF3 and EF4 PLC controlled pulses.

Session Leader Comments

Physics Operator Comments
May 9 2003 08:17:55:790AMJim IrbyWe will begin the run early today and try to debug noise on shunts, rogs, that is
large enough to affect the Hybrid and cause disruptions (pickup on Rogowskis).

Will start with full length EF3 and EF4 PLC controlled pulses.
May 9 2003 08:27:34:463AM1030509001Jim IrbyStart with EF3 pulse

Got it... nothing seen on shunts
May 9 2003 08:47:34:233AM1030509002Jim IrbyEF4 reverse bridge first

got it --- nothing seen
May 9 2003 09:16:28:240AM1030509003Jim IrbyEF4 Forward bridge

got it --- nothing seen
May 9 2003 09:53:04:467AM1030509004Jim Irby150 kA TF under PLC control

got it --- nothing seen
May 9 2003 10:26:58:293AM1030509005Jim Irbygas from 20 to 25 ms. pressure was .05 vs .065 mTorr yesterday

plasma --- nice startup --- no noise

kept rf off, also next shot...
May 9 2003 10:42:57:950AM1030509006Jim Irbyrepeat of shot 5

good shot --- no noise, no rf...


May 9 2003 11:36:37:673AM1030509007Jim Irbylong pause as we await the TF scanner to be repaired-------------------

gas from 25 to 24 ms

rf this shot

good plasma --- some rf heating

no noise on shunts.

TF scanner still didn't work....


Time (ms): 0 5 10 25
----------------------------------------
Ip (kA): -4.8266 -12.9732 -27.6262 -120.8333
dIp/dt (kA/ms): -0.9121 -2.3469 -4.1379 -7.3156
pressure (mTorr): 0.0640 0.0626 0.0633 0.0547
Bz0 (mT): -2.5100 -0.1889 2.6939 23.1796
Br0 (mT): -0.5731 -0.8940 -1.1725 -0.6168

Pressure down more than expected, but seems to work okay...
May 9 2003 12:02:58:787PM1030509008Jim IrbyArgon from 25 to 50 ms (John claims this is okay in L mode)

plasma --- some j-port coming on-line

nice rampdown

no noise, no scanner, Joe heads to the cell...
May 9 2003 12:40:40:920PM1030509009Jim Irbyrepeat after another long TF scanner pause

plasma

TF scanner is back

May 9 2003 12:50:52:697PM1030509010Jim Irbyrepeat

plasma --- 4.5 MW of rf !

no noise
May 9 2003 01:10:02:587PM1030509011Jim Irbygas from 24 to 23 ms

plasma

H/(H+D) around 12% --- came up with rf as usual

approaching 5 MW of rf, Wp about 80 kJ max

no TF scanner
May 9 2003 02:26:23:160PM1030509012Jim IrbyNoise problem again

plasma shutdown by 80 ms

going out to look at all the beaker contacts
May 9 2003 03:51:40:187PM1030509014Jim IrbyAll 13.8 breakers except ef3 have been inspected --- nothing was seen
If we have the problem again we will take time to look at ef3

Plasma but no rf

no noise

May 9 2003 03:52:32:657PM1030509015Jim Irbyrepeat

plasma --- rf and li pellet
May 9 2003 04:21:06:443PM1030509016Jim Irbyrepeat

nice plasma, just a little rf




May 9 2003 04:40:26:160PM1030509017Jim Irbyrepeat

plasma

TF scanner looks good
May 9 2003 05:03:31:587PM1030509018Jim Irbyplasma, but lost late because noise glitches did in Rogowskis
again.

got some rf, but no pellet.

Engineering Operator Comments
ShotTimeTypeStatusComment
108:14:16:520AMTestOkEF3 Test
208:33:21:383AMTestOkEF4 reverse
308:47:37:330AMTestOkEF4 Forward Test
409:16:30:643AMTestOkTF test shot
510:12:15:237AMTestOk
610:26:10:197AMPlasmaOk
711:25:51:320AMPlasmaOk
811:49:52:707AMPlasmaOk
912:25:31:003PMPlasmaOk
1012:38:40:687PMPlasmaOk
1112:51:54:320PMPlasmaOk
1201:07:06:800PMPlasmaBadTF Fast Circuit Ground Fault
1303:14:02:843PMTestOkScanner test
1403:23:48:663PMPlasmaOk
1503:38:19:003PMPlasmaOk
1603:52:07:750PMPlasmaOk
1704:23:34:913PMPlasmaOk
1804:37:02:017PMPlasmaBadNoise fault. TF breakers opened