Alcator C-Mod Run 1050201 Information

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Miniproposals
Miniproposal:399
Date Filed: 1/11/2005
Title:Initial Operation Using Digital Plasma Control System
First Author:Marco Ferrara
Session Leader:Steve Wolfe (shots 6-15)

Operators
Session leader(s):Steve Wolfe
Physics operator(s):Joseph Snipes
Engineering operator(s):Gary Dekow

Engineering Operator Run Comment
power system and gas system tests

Session Leader Plans

Physics Operators Plans
Entered: Feb 1 2005 12:48:16:877PM
Author: Joseph Snipes
Run plan for today is to do gas tests and hopefully some power tests if the computers will cooperate.

Session Leader Summaries
Entered: Feb 1 2005 07:04:48:920PM
Author: Steve Wolfe
Run summary for Tues. 2/1/2005
Gas system testing using dpcs (MP399 piggyback)

SL: wolfe
PO: snipes
EO: Dekow, Parkin
Operators : Tommy, Maria
Computer jockeys: jas, twf(in absentia)

>>> Gas setup:
>>> fill B-Top with 6 psi D2 Hybrid DISabled (PG4)
>>> fill B-side lower with 1 psi Ar Hybrid DISabled (PG1)
>>> fill B-side upper with 30 psi D2 Hybrid DISabled (PG2)
>>> fill (former) C-side with 30 psi D2 Hybrid DISabled (PG3)

Began trying to puff gas on shot#6, after numerous problems with datasystem,
some of which were in fact due to a bad interaction between dpcs:rt_action and
the dispatcher. The latter problem was solved by jas changing the p_init_check
script to do a dispatch/nowait instead of dispatch/wait.

We were successful in putting gas through pg4 (b-top) on shots 6 and 7.
Got the ratiomatic recording for shot 7 (needed to move the store sequence
for edge.gas.camac:incaa01 and incaa02 from 45 to 55; may be able to put this
back later.

We never got the gas valve waveforms to digitize. These are/were located in
crate 08 at B-C on the mezzanine, with a decoder in a different crate in
an adjacent rack. Joe Bosco found that the crate with the decoder was offline, and
after fixing that that the decoder had no clock. He thought he fixed that,
but the digitizer (spectroscopy.pha:pha_incaa16) stillwasn't triggering. This
didn't matter much because it looks like the inputs to the digitizer were
not present anyway. Apparently these racks were moved during the shutdown.
This situation needs to be fixed.

At any rate, our first attempts to get outputs from the B-side valves
B-sideMain (the former C-side) , B-side lower and B-side upper were unsuccessful.
As we were on the verge of giving up, Willy Burke pointed out that the fizzle
detector was preventing the valves from firing (all were programmed after .08sec)

After moving the f.d. to 0.9 sec, we got a weak response from C-side, and a stronger
response from B-side lower. After several exercising shots, we got what seems to
be appropriate response from all the valves. Probably a little more exercising
wouldn't hurt. DPCS seems to be putting out the correct demands on the fibers. This
completes the first part of day 1 of the MP399.

SHots of note (see logbook for more info):

7 : B-top puff - successful
8 : C-side puff - No gas
9 : B-side upper - No gas
10 : B-side lower - No gas
11 : C-side with f.d. moved late - few e-7 signal on ratiomatic
12 : B-side lower (pg1) early, C-side late - response from pg-1, somewhat late, no visible puff from C-side
13: Increase C-side voltage, bring in B-side Upper (pg2) later - see more from C-side, none from pg2
14: C-side only - 4e-4Torr this time
15: B-side upper, longer pulse - got 6e-5

Physics Operator Summaries
Entered: Feb 1 2005 06:35:55:453PM
Author: Joseph Snipes
We managed to exercise the gas valves a few times once the fizzle detector was moved back beyond the timing
for the gas puffs. All valves worked, though C-side needed a few shots to work correctly. Some data
acquisition problems with the gas signals were also found that need to be resolved tomorrow. We did 7 shots,
no plasmas.

Session Leader Comments
Feb 1 2005 03:52:27:093PM1050201006Steve WolfeStarting gas tests with dpcs
for shot#6: Enable Btop, standard pre-puff (running with seg1 only)

Had to move the sequence on gas camac incaa01 and 02 to get them to
store (they didn't on shot 5).

Ratiomatic is gronked (showing 10^7)
We saw gas on the gauge, but no traces.
Ratiomatic was off (it was on before the shot)
Feb 1 2005 03:57:28:813PM1050201006Steve WolfeWaveform traces from th evalves failed with
serial crate controller error
Joe B is investigating.
Feb 1 2005 04:52:36:343PM1050201007Steve WolfeShot7: Repeat B-top, hopefully with data from the valves and ratiomatic
Got gas. Ratiomatic worked. Shows 1.5e-5 at the right time.
Gas valve signals still missing. Joe and Yuri thought they had the crate back online.
Feb 1 2005 05:00:43:220PM1050201008Steve WolfeShot8: Enable the B-sideMain (former C-side) valve
The valve signals are not connected to the digitizer,
and the decoder clock fiber is not connected. Those signals
are not going to happen today.

No gas from the pg3. No way to tell why, since we don't have the gas valve signals.
There is a pulse in the interface room, over 100msec worth, and
I saw the HV enable come on.
So the main gas isn't working for now.
Could be the connection, or Willy's driver board, or the fiber from the interface
room. No way to tell.
Feb 1 2005 05:13:43:577PM1050201009Steve WolfeShot9: Enable B-side upper (pg2)
Joe thinks the decoder is now clocking again

No gas on the gauge. No signal on ratiomatic.
Still no trigger on the pha_incaa

Move on to B-side lower
Feb 1 2005 05:19:16:937PM1050201010Steve WolfeShot10: Move on to B-side lower (100ms puff)
No gas.

So we are 1 for 4 on gas valves.
Feb 1 2005 06:02:34:047PM1050201011Steve WolfeShot11: Willy points out that the fizzle detector will inhibit
the gas. Move f.d. to 0.9sec and try again on C_side

gas on the gage, Very small gas rise, though, only a few 10-7

next shot: move pg1 (b-side lower) to -.4 sec and leave pg3 on.
Feb 1 2005 06:11:27:500PM1050201012Steve WolfeShot12: move pg1 (b-side lower) to -.4 sec and leave pg3 on.

Lots of gas this time, Starts at -.17 gets to 1.6e-5
No sign of the gas from pg3?

Next shot: B-side upper at .5sec (pg2), c-side at 100V at .026sec
Feb 1 2005 06:18:50:150PM1050201013Steve WolfeShot13: B-side upper at .45sec (pg2), c-side at 100V at .026sec
got gas, rises at about 0.2sec . No second puff at .45.
Feb 1 2005 06:21:05:950PM1050201013Steve WolfeShot13: B-side upper at .45sec (pg2), c-side at 100V at .026sec
got gas, rises at about 0.2sec . No second puff at .45.

next shot: c-side only
Feb 1 2005 06:27:31:007PM1050201014Steve WolfeShot14: c-side only
got 4e-4 on the big board gauge, that's more like it!
Still has some delay, starts to rise at .09 on pulse that starts at .026

Next shot: B-side upper for 150msec
Feb 1 2005 06:33:09:047PM1050201015Steve WolfeShot15:B-side upper for 150msec starting 0.35sec
gas shows up at 0.4sec, gets to 6e-5

Looks like the valves just needed exercising.

RUN DONE

Physics Operator Comments
Feb 1 2005 03:30:43:767PM1050201006Joseph SnipesShot 6: Setup pulse_gas 1 with 100 V from 0.25 to 0.3 s and pulse_gas 2 with 100 V from 0.45 to 0.5 s.
Feb 1 2005 04:31:21:017PM1050201007Joseph SnipesShot 7: Repeat with B top enabled again.
Feb 1 2005 04:53:15:767PM1050201008Joseph SnipesShot 8: Repeat with B top disabled and C-side enabled.
Feb 1 2005 04:58:53:483PM1050201008Joseph SnipesShot 8: Repeat with B top disabled and C-side enabled. No gas visible in the machine.
Feb 1 2005 05:07:34:580PM1050201009Joseph SnipesShot 9: Repeat with B side upper only enabled. No gas visible in the machine.
Feb 1 2005 05:15:44:140PM1050201010Joseph SnipesShot 10: Repeat with B side lower only enabled. No gas visible in the machine.
Feb 1 2005 05:55:22:127PM1050201011Joseph SnipesShot 11: Repeat with C side only enabled and with the fizzle detector set to 0.9 s. No gas visible in
the machine. Got gas. Apparently, the fizzle detector was the problem.
Feb 1 2005 06:12:48:127PM1050201012Joseph SnipesShot 12: Moved pulse gas 1 (B side lower) to -0.4 s at 100 V until -0.2 s. Enabled C-side and B-side lower.
Gas comes up at -0.179 s perhaps B side lower was delayed for some reason.
Feb 1 2005 06:17:28:837PM1050201013Joseph SnipesShot 13: Increased C-side voltage to 100 V for about 0.1 s from 0.026 sec to 0.128 s. Enabled C-side and
B-side upper. Got gas but it begins to rise at about 0.16 s, which is not at the right time for either valve.
Feb 1 2005 06:28:06:410PM1050201014Joseph SnipesShot 14: Enabled only C-side. Got a lot of gas. Timing looks about 75 ms late.
Feb 1 2005 06:32:47:703PM1050201015Joseph SnipesShot 15: B-side upper enabled only. Set its pulse to 150 ms duration from 0.35 to 0.5 s. Got gas. Timing is
a bit delayed but about right starting around 0.4 s.

Engineering Operator Comments
ShotTimeTypeStatusComment
101:31:01:940PMTestBad
202:10:41:390PMTestBaddpcs hung
302:48:04:127PMTestBad
403:11:29:140PMTestOk
503:18:09:470PMTestOk
603:42:27:063PMTestOkpuffed gas with dpcs
704:30:56:907PMTestOk
804:56:10:547PMTestOk
905:05:20:123PMTestOk
1005:14:06:797PMTestOk
1105:53:42:140PMTestOk
1206:03:05:030PMTestOk
1306:12:31:813PMTestOk
1406:22:12:990PMTestOk
1506:29:26:520PMTestOk