Alcator C-Mod Run 990819 Information

Miniproposals

Miniproposal: 214

Date Filed: 1/5/1999

Title: D and E-port RF System Commissioning

First Author: Steve Wukitch

Session Leader: Rejean Boivin (shots 1-1)

Session Leader: Steve Wukitch (shots 1-1)

Operators
Session leader(s):	Rejean Boivin,Steve Wukitch
Physics operator(s):	Steve Wolfe
Engineering operator(s):	Bill Cochran,Frank Silva

Engineering Operator Run Comment
MP #214

Session Leader Plans

Physics Operators Plans

Session Leader Summaries

Physics Operator Summaries

Entered: Jul 7 2004 04:37:08:397PM

Author: To Be Determined

Physop Summary for Thursday 990819

MP#214 ICRF Conditioning
or
MP#228 SOL Transport

SL: Wukitch/Boivin or LaBombard
PO: Wolfe
EO: Silva,Cochran

The primary goal of today's run was to optimize heating with the J-port
antenna (FMIT#3 & 4). The backup plan was to run ohmic H-modes for the SOL
transport and other H-mode interests, if the RF was out of commission. Neither
goal was accomplished.

The screen crowbar unit blew in FMIT#3 just before we were ready to start the
run. A spare was installed, but much time was spent locating fuses to replace
those which had blown. The screen crowbar was then tested (on a 1/4W, 10Ohm
resistor) and failed the test, i.e. the resistor smoked. We then decided to go
to plan B and run ohmic H-modes, with LaBombard as Session Leader.

Shot #1 was based on 990818009, and ran successfully with a good ohmic H-mode.
The session leader reported that the FSP target was moving away during the
H-mode, and an a decreasing ZCUR was programmed and loaded for the next shot.

However, the PF breaker failed to close before shot #2, and it was determined
that the breaker charging motor had failed. No spare being on hand, it was
necessary to terminate the run.

Scorecard: 1 shot, 1 plasma, 1 H-mode.

Session Leader Comments

Physics Operator Comments

Aug 19 1999 08:43:29:640AM Steve Wolfe Run Plan for Thursday, 8/19/1999

Run to start at 10AM and continue until 6PM.

SL: Wukitch/Boivin
PO: Wolfe

MP 214 -- RF conditioning
Continue RF conditioning on J-port
Start with standard 1MA 5.4T plasmas (like 990818002) and try to
optimize heating with J3 and J4 running together. Possibly change
to ohmic H-mode plasmas (like 990818009) if results warrant.

Engineering setup
Setup power supplies from 990818002

Two hours of ECDC in D2 prior to the run.

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

The following gate valves should be enabled, assuming no vacuum problems:
ECE, VUV

Aug 19 1999 08:50:41:090AM Steve Wolfe Import segment 2 from 990818002.
Reduce TF current to -142000 (5.1T) in both segments 1 and 2
Load into model
Do coldstart; log ok.

Aug 19 1999 09:21:40:577AM Steve Wolfe Import seg 2 from 990818009 (ohmic H-mode shot) into segment 3 (leave off).

Aug 19 1999 09:34:20:733AM Steve Wolfe Blip reports that the wide angle tv view (ch33) has had the filtering
reduced from ND3 to ND2, and the view widened to include more of
the J-antenna, for today's run.

Aug 19 1999 12:03:35:043PM 990819001 Steve Wolfe Shot #1: Like 990818002, except tf reduced to 5.1T (142kA).
Disable Ar (B-side lower) until someone complains
Delay while the RF'ers fix/replace the #3 screen crowbar unit,
which just failed.
We almost changed to ohmic H-mode run, but Sam and/or Andy found
two replacement fuses. Reload as described above.
Failed the crowbar test.
Back to plan B, do ohmic H-modes: load with segment #3.
LaBombard is now Session Leader

Result: plasma, H-mode from .73 to 1.07s; looks like an injection kills
the H-mode.
slow current rise in startup

Next shot: Drop pre-puff, try holding FSP target lower during H-mode.

Aug 19 1999 12:30:14:653PM 990819001 Steve Wolfe Shot #2: Drop pre-puff from 22->18msec
try holding FSP target lower during H-mode by moving ZCUR down 5mm.

PF Breaker won't go in. Need to pull it to evaluate (1/2 - 1hr);
may be done for the day.

Aug 19 1999 02:12:35:513PM 990819001 Steve Wolfe Shot set up that would have been shot 990819002 is now
saved in CMOD$TEST_SHOTS:[HYBRID.PCS] shot 990820999, in
case it is wanted.

Engineering Operator Comments

Shot Time Type Status Comment

1 11:54:27:873AM Plasma Ok no faults

Physics Operator Comments
Aug 19 1999 08:43:29:640AM		Steve Wolfe	Run Plan for Thursday, 8/19/1999 Run to start at 10AM and continue until 6PM. SL: Wukitch/Boivin PO: Wolfe MP 214 -- RF conditioning Continue RF conditioning on J-port Start with standard 1MA 5.4T plasmas (like 990818002) and try to optimize heating with J3 and J4 running together. Possibly change to ohmic H-mode plasmas (like 990818009) if results warrant. Engineering setup Setup power supplies from 990818002 Two hours of ECDC in D2 prior to the run. Gas setup - fill B-top with 6 psi of D2 Hybrid enabled fill B-side lower with 1 psi of Ar Hybrid enabled fill B-side upper with 6 psi of H2 Hybrid DISABLED fill C-side with 30 psi of D2 Hybrid enabled leave J-bottom as is Hybrid DISABLED The following gate valves should be enabled, assuming no vacuum problems: ECE, VUV
Aug 19 1999 08:50:41:090AM		Steve Wolfe	Import segment 2 from 990818002. Reduce TF current to -142000 (5.1T) in both segments 1 and 2 Load into model Do coldstart; log ok.
Aug 19 1999 09:21:40:577AM		Steve Wolfe	Import seg 2 from 990818009 (ohmic H-mode shot) into segment 3 (leave off).
Aug 19 1999 09:34:20:733AM		Steve Wolfe	Blip reports that the wide angle tv view (ch33) has had the filtering reduced from ND3 to ND2, and the view widened to include more of the J-antenna, for today's run.
Aug 19 1999 12:03:35:043PM	990819001	Steve Wolfe	Shot #1: Like 990818002, except tf reduced to 5.1T (142kA). Disable Ar (B-side lower) until someone complains Delay while the RF'ers fix/replace the #3 screen crowbar unit, which just failed. We almost changed to ohmic H-mode run, but Sam and/or Andy found two replacement fuses. Reload as described above. Failed the crowbar test. Back to plan B, do ohmic H-modes: load with segment #3. LaBombard is now Session Leader Result: plasma, H-mode from .73 to 1.07s; looks like an injection kills the H-mode. slow current rise in startup Next shot: Drop pre-puff, try holding FSP target lower during H-mode.
Aug 19 1999 12:30:14:653PM	990819001	Steve Wolfe	Shot #2: Drop pre-puff from 22->18msec try holding FSP target lower during H-mode by moving ZCUR down 5mm. PF Breaker won't go in. Need to pull it to evaluate (1/2 - 1hr); may be done for the day.
Aug 19 1999 02:12:35:513PM	990819001	Steve Wolfe	Shot set up that would have been shot 990819002 is now saved in CMOD$TEST_SHOTS:[HYBRID.PCS] shot 990820999, in case it is wanted.

Engineering Operator Comments
Shot	Time	Type	Status	Comment
1	11:54:27:873AM	Plasma	Ok	no faults