<!-- Title: 15:20:39  Thu Feb  6 2003 -->
<!-- Crewchief: Morris Binkley -->
<!-- Op1: Aseet Mukherjee -->
<!-- Op2: Bob Wagner -->
<!-- Op3: &nbsp; -->
<!-- Op4: &nbsp; -->
<!-- Op5: &nbsp; -->
<!-- Op6: &nbsp; -->
<!-- Notes: -->
<pre>Continuation of COT work during January/February 2003 access.</pre>


<!-- Date: Thu Feb 6 15:30:37 2003 -->
On January 28, 2003 we fixed a problem with SL8_S11a which had been tripping.  With current transformers we determined that there was an intermittent HV connection. Spike runs157418 and 157425 localized the problem to cell 72.  We visually determined that HV ribbon cable not well connected for cell 72 and that connector crimp was also bad.  Also the cap meter indicated that S11 in cell 72 did not have correct capacitance.  Recrimpted cable and reseated connector.  All appears OK now.  
<!-- Author: Bob, Morris, Wojciech, Wanda -->


<!-- Date: Thu Feb 6 15:34:38 2003 -->
<table><tr><td><a href=/elog/notebooks/cot/Thu_Feb__6_2003_153418.ps align=top><img src=/cgi/elog/det-system-elog.pl?nb=cot&action=view&page=-132  align='top'></td><td>This picture shows the typical scope trace from the transformers when there is a HV glitch due to a bad connection of the HV ribbon cable.  Trace 2 is SL8_S11a and Trace 4 is SL8_S11b.  </a></td></tr></table>
<!-- Author: Morris -->


<!-- Date: Thu Feb 6 15:41:00 2003 -->
<pre>On Jan 29, 2003 find that SL8_S11a still triping. Taking COT HV spike runs localized the cell to Cell_03.  On Jan 30, SL8_Cell03_S11 was disconnected on the HV daughterboard.  Problem then appeared fixed.</pre>
<!-- Author: Morris, Bob, et.al. -->


<!-- Date: Thu Feb 6 15:47:01 2003 -->
<center><a href='/elog/notebooks/cot/Thu_Feb__6_2003_154349.ps'><img src='/cgi/elog/det-system-elog.pl?nb=cot&action=view&page=-134' ></a><a href='/elog/notebooks/cot/Thu_Feb__6_2003_154526.ps'><img src='/cgi/elog/det-system-elog.pl?nb=cot&action=view&page=-136' ></a></center>
<!-- Author: Morris -->
<!-- Comment: Thu Feb  6 15;53;36 comment by...Morris -->
<pre>The first plot shows a HV current spike due to a discharge in SL8_S11a.  QuadA is channel 4, QuadB is channel 3, and the trigger signal for the COT HV spike run is channel 1.  The second plot shows another discharge with the same channel assignments.  However, this second discharge probably happened after the fix on January 30 suggesting that there is yet another problem is SL8_S11.  If this is true, it does not cause trips at a significant rate.</pre>


<!-- Date: Wed Feb 12 00:06:49 2003 -->
<pre>Some information regarding the SL7 trips earlier this evening from the COT2 Master window (not all of which go to Trip.log). 
 
18:54:15 Ramp to 100% 
20:10:33 SL7 S0 "I alarm" to iFix 
20:24:20 SL7 S4 SOC trip 
20:25:12 Ramp back to 100% 
21:00:56 SL7 S3 "I alarm" to iFix 
21:00:59 SL7 S3 SOC trip 
21:01:22 Ramp back to 100% 
21:03:35 thru 21:03:37 SL7 S3 "I alarm" to iFix 
21:03:38 SL7 S3 SOC trip.  Ting called this time 
21:09:16 Ramp back to 100% 
21:54 Tev quench.  Doesn't cause any trip.  HV left on. 
22:19:00 SL7 S0 SOC trip 
 
There are notes about high losses during this shift, though the 
exact time when it became "OK" is not clear from the e-log. 
 
For now I am setting SL7 to 40% (local at COT2) so the rest can 
be turned on for cosmic ray tests.</pre>
<!-- Author: Aseet -->


<!-- Date: Sat Feb 15 15:52:08 2003 -->
<pre>There was an OC trip on SL8_S0 as high voltage was being brought up at the begining of the store last night (February 14).  The ramp from 40% started at 21:46:01 and the trip was at 21:48:45 .  The event number was 0 so presumably the run had not started.</pre>
<!-- Author: Morris -->


<!-- Date: Sat Feb 15 16:01:35 2003 -->
<table><tr><td><a href=/elog/notebooks/cot/Sat_Feb_15_2003_160130.ps align=top><img src=/cgi/elog/det-system-elog.pl?nb=cot&action=view&page=-138  align='top'></td><td>We have also been getting lots of discharges on SL8_11a.  In this picture, SL8_S11a is channel 4 and SL8_s11b is channel 3.  It presumably was during the current store 2231 (scraping complete at 11:23 Feb 15).  According to the scalers there have been a few discharges on this channel since the begining of the store.  The amplitude and risetime looks very large suggesting that perhaps it is a discharge external to the chamber.</a></td></tr></table>
<!-- Author: Morris -->
<!-- Comment: Sat Feb 15 16;14;02 comment by...Morris -->
On closer examination, there have been no discharges scaled during this store.  Therefore this scope trace was probably from the previous store.  There were 2 discharges scaled:  one at 04:29 and one at 05:10.


<!-- Date: Mon Feb 17 09:44:50 2003 -->
There was considerable activity over the weekend with SL8 HV.  There were two more trips.  On Feb 15 at 23:34:21 there was a SL8_S1 SOC trip (no run active).  On Feb 16 at 20:19:48 there was a SL8_S0 SOC trip (run 158880, ev 1303812).  Both of these trips were accompanied by multiple counts on the SL8_S11a scaler during the previous second suggesting they are in quadrant A.
<!-- Author: Morris -->


<!-- Date: Mon Feb 17 21:49:25 2003 -->
We now have a trigger bit in the standard physics table.  We are now taking a run with SL8_S11a (scalar 0), SL8_S1a (scalar 1), and SL8_s0a (scalar 2) all ored together to make the trigger signal.  We are running Run 158976.  Our data is going to stream A and therefore should be on disk in the look area.  I think we are trigger bit 43 (the descriptor is the only one with "cot" in it).  All three of these channels go into a LeCroy discriminators set at 30mv (assumes looking for negative pulse, i.e. that problem is in quad A). They are ored together before being sent to the 2nd floor and the or is also used to tigger the scope on the 1st floor.  We are about 1:45 into the run and still have no counts (or trigger).
<!-- Author: Morris -->


<!-- Date: Mon Feb 17 22:54:31 2003 -->
The run with the new trigger table was stopped so some quantities could be checked versus their values with the old trigger table.  For 45 minutes of this time I reversed the transformer polarities for SL8_S0a and SL8_S1a to see if there were any discharges in the other quadrants.  There were none in 45 minutes.  The transformers are now returned to their original polarity (assuming the problem is in quad A) in preparation for returning to the new trigger table with the COT spike trigger.
<!-- Author: Morris -->


<!-- Date: Fri Feb 21 10:09:28 2003 -->
During the owl shift we sent 5 trigger pulses to the DAC during run 159175.  The following is a chronology:  at 02:12 from SL8_S11a; at 03:25 from SL8_S11a; at 04:23 from SL8_s11a; at 06:27 from SL8_S0a and SL8_S1a; at 6:29 from SL8_S0a and SL8_S1a.  I am working on filtering off the events from the look area.
<!-- Author: Morris -->


<!-- Date: Fri Feb 21 10:25:32 2003 -->
<table><tr><td><a href=/elog/notebooks/cot/Fri_Feb_21_2003_102526.ps align=top><img src=/cgi/elog/det-system-elog.pl?nb=cot&action=view&page=-140  align='top'></td><td>The scope trace for the 06:29 trip of SL8_S0a and SL8_s1a.  The two pulses seem perfectly in time and there is no hint of activity on SL8_S11a.  </a></td></tr></table>
<!-- Author: morris -->


<!-- Date: Sat Feb 22 11:16:42 2003 -->
<center><a href='/elog/notebooks/cot/Sat_Feb_22_2003_111607.ps'><img src='/cgi/elog/det-system-elog.pl?nb=cot&action=view&page=-142' ></a><a href='/elog/notebooks/cot/Sat_Feb_22_2003_111621.ps'><img src='/cgi/elog/det-system-elog.pl?nb=cot&action=view&page=-144' ></a></center>
<!-- Author: morris -->
<!-- Comment: Sat Feb 22 11;43;44 comment by...morris -->
CDF run 159199 was started (for a new store) at about 19:00 on Feb 21 and by about 21:00 we had sent 8 spike triggers to the DAQ.  There have been no more spikes since 21:00 although the store is continuing as I write.  The two above pictures show the last spike on two different time scales.  The large pulse is on SL8_S0a (chn3).  There is a small pulse on SL8_S1a (chn2).  There is no signal on SL8_S11a (chn4).  The time stamps of the 8 spikes are as follows:  scalar 0: 19:24:35; scalar 0  19:33:00; scalar 0  20:00:43; scalar 1,2  20:02:03;  scalar 0  20:16:59; scalar 1,2  20:49:14; scalar 1,2  20:53:02; scalar 1,2  20:57:07 (note: scalar 0 is SL8_S11a, scalar 1 is SL8_S1a, scalar 2 is SL8_S0a).  The events from these spike triggers are in my "cottrip" area on fcdfsgi2 in the r159199x.dat files.  

<!-- Comment: Sat Feb 22 12;48;15 comment by...morris -->
We seemed to have missed the 4th SL8_S11a trigger (20:16:59).  Perhaps the run was stopped?  In any case, r159199a.dat seems to have the first S11a trigger; r159199b.dat has the 2nd and 3rd S11a triggers and the first SL0,1a trigger; r159199d.dat has the 2nd, 3rd, and 4th SL0,1a triggers.  Event 348218 in the first series of events on r159199b.dat is the only S11a event that has a "blast."  


<!-- Date: Sun Feb 23 10:43:15 2003 -->
<center><a href='/elog/notebooks/cot/Sun_Feb_23_2003_104235.ps'><img src='/cgi/elog/det-system-elog.pl?nb=cot&action=view&page=-146' ></a><a href='/elog/notebooks/cot/Sun_Feb_23_2003_104248.ps'><img src='/cgi/elog/det-system-elog.pl?nb=cot&action=view&page=-148' ></a></center>
<!-- Author: morris -->
<!-- Comment: Sun Feb 23 10;53;58 comment by...Morris -->
During the store on the Saturday Feb 22 evening shift we got three spikes on SL8_S11a during run 159228.  There was no activity on SL8_S0a or SL8_S1a.  The time stamps were as follows: reset - 17:01:16; SL8_S11a spike - 18:31:33; trip SL3_S2 (SOC) - 19:26:05; SL8_S11a - 21:21:30; SL8_S11a - 21:23:59.  The two above scope traces show the spike for the 3rd spike (last time stamp) on for two different sweep speeds.  I am stripping the appropriate events and putting them on fcdfsgi2 as I write.


<!-- Date: Mon Feb 24 09:37:05 2003 -->
<center><a href='/elog/notebooks/cot/Mon_Feb_24_2003_093552.ps'><img src='/cgi/elog/det-system-elog.pl?nb=cot&action=view&page=-150' ></a><a href='/elog/notebooks/cot/Mon_Feb_24_2003_093611.ps'><img src='/cgi/elog/det-system-elog.pl?nb=cot&action=view&page=-152' ></a><a href='/elog/notebooks/cot/Mon_Feb_24_2003_093633.ps'><img src='/cgi/elog/det-system-elog.pl?nb=cot&action=view&page=-154' ></a></center>
<!-- Author: morris -->
<!-- Comment: Mon Feb 24 09;50;35 comment by...morris -->
The above three scope traces have the following history.   The one on the left is a small pulse on SL8_S11a taken when ramping the voltages on SL3 and SL4 (during pulse transformer switch) early Sunday afternoon Feb 23.  There was no run in progress at the time.  The middle pulse came at 07:20:37 this morning Feb 24 at about the time the beam was lost with a quench.  Here there is indication of activity on all traces (recall blue and violet are SL8_S0a and SL8_S1a).  The far right pulse is for SL3_S2a.  There is no time stamp for this.  It may of happened during the quench. There were also SL8_S11a spike triggers at 04:34:38 (during a silicon calibration), 23:35:59, and 23:35:26. 


<!-- Date: Mon Feb 24 16:27:04 2003 -->
<table><tr><td><a href=/elog/notebooks/cot/Mon_Feb_24_2003_162649.ps align=top><img src=/cgi/elog/det-system-elog.pl?nb=cot&action=view&page=-158  align='top'></td><td>This is the scope picture for SL8_Slla that goes with events 245853-5 of file r159288a.dat (taken early this afternoon Feb 24).  All three events show evidence of a blast and the last in particular points to cell 29 according to Bob. </a></td></tr></table>
<!-- Author: Morris -->


<!-- Date: Sun Mar 16 09:02:04 2003 -->
<pre>Sun Mar 16 08:59:31 With the record luminosity, the current for SL2-S11 came too close to the software current limit and produced an I-alarm (normally used to catch long current discharges). The current draw on SL2-S11 is ~225ua and on SL1-S11 is ~200 ua at 40E30. I raised their software current limits from 250ua to 275ua. - R.Wagner  
</pre>
<!-- Author: R. Wagner -->
<!-- Comment: Mon Mar 17 06;35;50 comment by...R. Wagner -->
<pre>The COT was at full voltage for about 1/2 hour before the beam was lost and SL2-S0 tripped on SOC.</pre>


<!-- Date: Thu Mar 20 09:18:29 2003 -->
<pre>Another record store, 40.75E30.  Before raising the HV, Morris and I increased the SL1-S11 and SL2-S11 current limit from 275ua to 300ua.  After raising the voltage, SL2-S0 gave an I alarm, so we raised its software limit to 300ua also.</pre>
<!-- Author: M. Binkley, R. Wagner -->


<!-- Date: Mon May 5 11:10:30 2003 -->
<pre>Got several spikes on SL8-S1B in the last store.  Appears to be the same area as before, probably cell 162.  Re-inserted diode box, set up extra supply, and put SL8-S1B 40V below nominal (actually 10V*101.5%).</pre>
<!-- Author: Aseet, Bob -->


<!-- Date: Mon May 12 10:26:00 2003 -->
<table><tr><td><a href=/elog/notebooks/cot/Mon_May_12_2003_102523.ps align=top><img src=/cgi/elog/det-system-elog.pl?nb=cot&action=view&page=-160  align='top'></td><td> This spike trigger occurred during run 162686 at 5/9/03, 17:10:09.   Trace 2 is SL8_S1b (single supply), trace 3 is  SL8_S2b, and trace 4 is SL8_S3b.  There were 4 event that  Bob found centered around cell 162 (or possibly 163).</a></td></tr></table>
<!-- Author: Morris Binkley -->


<!-- Date: Mon May 12 17:22:23 2003 -->
<table><tr><td><a href=/elog/notebooks/cot/Mon_May_12_2003_172211.ps align=top><img src=/cgi/elog/det-system-elog.pl?nb=cot&action=view&page=-166  align='top'></td><td>Sometime this afternoon we got another spike on sl3_s2a. Since the trace is positive, it presumably means that the  discharge is in quadrant b, c, or d.  The scope trace is on the left.</a></td></tr></table>
<!-- Author: Morris Binkley -->


<!-- Date: Thu May 15 09:16:35 2003 -->
<table><tr><td><a href=/elog/notebooks/cot/Thu_May_15_2003_091608.ps align=top><img src=/cgi/elog/det-system-elog.pl?nb=cot&action=view&page=-168  align='top'></td><td>There was a flurry of spikes on SL8_S1b last night  May 14th.  There were 15 between 22:21 and 22:33 and then  the activity stopped. The scope trace on the left is for the last spike at 22:33.  It looks about the same as the one on May 12th.  Remember that SL8_S1b is on a separate supply, so  the current spike is not so large.</a></td></tr></table>
<!-- Author: Morris Binkley -->


<!-- Date: Tue Jun 24 09:26:04 2003 -->
<h3>When do the repeater cards fail</h3> 
Just for the record books, we had a questionable <a href= 
'http://www-cdfonline.fnal.gov/cgi/elog/elog.pl?nb=2003&action=view&page=521&frame=2&anchor=14:33:33.905'> 
12V on a COT crate</a> which powers 3.3V DC DC converter which supplies the 3.3 V to the repeaters.  So we 
did an experiment with a TDC driving two repeater cards on one 
cable, with a variable 12V supply on the crate.  We found that 
one repeater card lost significant voltage loss at 5.5 V, the other at 4.5 V.   
The nominal current draw of 0.09 A went up to 0.12 A even at 6 V, but both cards still had > 3V.<P> 
Conclusion: The DC-DC converters will work even a 6V on the TDC crate.
<!-- Author: SCN, Morris, Mike K, Roberto Davila -->


<!-- Date: Sun Sep 28 13:55:52 2003 -->
<pre>Bob found the HV supplies would not turn on.  Turned out to be some problem at the far end of the hardware trigger inhibit.  (We are supposed to replace this before the end of the access.) 
 
I disconnected the trigger inhibit cables from the BiRa system.  Checked that the trip daisy chain is still OK.</pre>
<!-- Author: Aseet -->


<!-- Date: Sun Nov 16 23:13:06 2003 -->
<pre>Happened to wander by and noticed SL7 S1, S3 draing current and S2 sinking current.  S2 voltage was low by ~800V (running ~1900V instead of correct ~2700V).  Trying it at 10%, find S2 puts out almost no voltage.  Looks like a bad pod.   
 
Ace on shift says it's been this way since Friday at least (start of his shift).  Think I (or Morris) would have noticed it Friday day, so guessing it's been this way since Friday evening. 
 
When preparing to replace pod, find module is quite warm. 
 
Removed pod 546468, marked BAD and put in cleanroom.  Installed 547029.  Looks OK.</pre>
<!-- Author: Aseet Mukherjee -->


<!-- Date: Wed Nov 19 11:25:56 2003 -->
<pre>Yesterday COT2 got into a strange state where the Master program did not have enough resources to operate properly.  The number of free machine cycles was essentially zero rather than the more typical 40%.  This condition was discovered because the shiftcrew noticed a missing COT heartbeat on IFIX.  One of the symptoms was that the taskbar that allows one to ramp all superlayers together was missing on the HV display window.  There was difficulty in ramping the high voltages down.  The problem was solved by stopping all programs and then restarting IFIX and MCS.  </pre>
<!-- Author: Morris -->


<!-- Date: Thu Nov 20 10:06:32 2003 -->
The low voltage power UNW has tripped off 4 times since 19:00 yesterday.  The first 3 times, it was off only briefly and then could be reset.  The last time it went off at 08:50 and is still off at 10:05.  It is presumably connected to the solid state relay that we had trouble with earlier.
<!-- Author: Morris -->


<!-- Date: Mon Nov 24 01:27:10 2003 -->
Two Sl7 S0 software overcurrent trips within a few minutes.  Was here for the 2nd one, current on S0 and S1 started to rise a bit below 90% (before slow ramp kicked in).  S0 was drawing ~200uA for the 1 second before the trip, S1 ~75uA.  S0 current rose rapidly toward the end, ending with a spike of ~280uA (software limit is 250uA).  S2 is slightly high (10uA, others ~5uA), all other channels look normal.  Luminosity was 8.4e30 
 
Trying to find where the problems start, notice S1 and S3 are very noisy even at 90%; S0 and S2 are quiet.  After a few minutes current on S0 and S1 jumps up, so turn off.  Hooked up extra supply to isolate quadrant ... it's quadrant A.  This time it took ~8minutes at 100% to start drawing current.  Once going, it stays high down to ~50%.   
 
Given problem on the weekend of 16 Nov, guessing this is a damaged HV daughterboard.  To run without repairs we need to disable at least S0 and S1, and drop S2 somewhat (to get S0 below 90%, since it has drawn current at 90%).  Prefer not to let it run un-attended, so leave it off for the night, assume we can continue in the morning.
<!-- Author: Aseet -->


<!-- Date: Tue Nov 25 00:28:45 2003 -->
<pre>Disconnected all SL7 quadrant A.  Also removed "special" supplies from SL3 and SL8 (and SL7).  Made SL7 available for control (to 100%) again. 
 
Hooked up new trigger inhibit board to trip daisy chain and to cable from inhibit system.  LEDs (monitoring outputs) work properly but not sure how to tell if the inhibit is working.</pre>
<!-- Author: Aseet -->


<!-- Date: Fri Dec 5 00:12:13 2003 -->
Found a store in when I got here.  Apparently been going for some time.  Currents on SL2 S5 at L=11.46e30 are 21.6 lower (quad C&D) and 23.7 upper (quad A&B).
<!-- Author: Aseet -->


<!-- Date: Mon Dec 15 17:53:10 2003 -->
We noticed spikes in SL7 S6,S7,S8 and sometimes a few others.  Looking was motivated by a trip in SL7_S6 earlier in the afternoon.  We changed two of the transformers to SL7_S6b and SL7_S8b and set them up with the polarity to trip on any of the other 3 quadrants.  Over a period of about 20 minutes we got about 12 spike triggers on S6 and 2 on S8.  We tried to have run 176446 active during this time.  We may have a few spike triggers on it, but the MCR called and said they were injecting beam before we got everything set up properly.  
<!-- Author: Morris, Aseet, Bob, Kevin -->


<!-- Date: Mon Dec 15 17:55:55 2003 -->
<table><tr><td><a href=/cgi/elog/det-system-elog.pl?nb=cot&action=view&page=-169&button=yes target='xxx' onclick='jswindow()'; align=top><img src=/cgi/elog/det-system-elog.pl?nb=cot&action=view&page=-169  width='300' align='top'></a></td><td>This is the scope for one of the spike triggers for SL7_S6b perhaps taken during run 176446.</td></tr></table>
<!-- Author: Morris -->
<!-- Comment: Mon Dec 15 17;57;36 comment by...Morris -->
Note that trace 2 (blue) is SL8_S1b and trace 4 (green) is SL7_S8b.


<!-- Comment: Fri Dec 19 13;01;12 comment by...Morris -->
Note that when we are looking at the HV current in one quadrant and the discharge (spike) is in another quadrant, we get the sort of trace seen above for SL7:  about 150mv high and a decay time of 30-40usec.  If the current transformer is on the same quadrant as the discharge, the height of the pulse increases to about 400mv.  This was seen for the S9 discharge in quadrantA with the transformer moved to quadrantA.  The sign, of course, changes if the transformer is in the same quadrant as the discharge.  Finally, if the transformer is on the same quadrant as the discharge and this quadrant is on a separate BiRa supply, the pulse height decreases to about 60mv, at least for the S9 discharges in quadrantA.
<!-- Date: Wed Dec 17 12:27:02 2003 -->
<p>Between 17:40 yesterday and 11:00 today we had the COT high voltage on for all but about an hour about 0500 this morning.  Before turning on, the HV current transformers in SL7 for the spike trigger were switched as follows:  S6b-->S7b and S8b-->S9b. They were hooked up to be sensitive for spikes in all quadrants except quadrant b.   During this roughly 16 hours (960 minutes) or HV, we had 84 spike triggers:  61 on S7b and 23 on S9b.  During a period of less than a minute around 11:30 last night, we had >40 spike triggers on S7b.  There was no trip and after that burst S7b was very quiet with only a couple of more spikes.  Hopefully keeping the high voltage on helped condition the chamber.  I looked an a few of the triggers on the scope and they all looked similar to the trace shown above with about 150mv pulse height. </p>    
<p>We will have to watch the chamber carefully when we try to bring it back on with beam.  The first time it sees beam, I would let it sit for 10 minutes at 90% and then another 10 minutes at 95% and then anther 10 minutes at 98% before bringing to full voltage.  I think the instructions are to have a COT expert there to raise the voltage.  If there is more that one trip on SL7, then Bob suggested trying to run it at 98.5% which is roughly the level of SL1 and SL3.  If that doesn't work, we have to lower it until it doesn't trip. </p>
<!-- Author: Morris -->


<!-- Date: Thu Dec 18 18:47:04 2003 -->
<pre>The store went in today with an initial luminosity around 50E30. 
We took SL7 up to ~98.5% of nominal, same as SL1 and 3.  Initially, 
it was not too bad, but the rate of spikes on S9 grew to ~1Hz. 
We tried lowering S9 and S10 as well, but eventually had to take 
all of SL7 down to 90% for it to stabilize. 
 
We switched the transformers to both trigger on S9 for different 
quadrants, and localized the spikes to quadrant A.  For quad A, 
S8-S11 are now on separate supplies.  The voltages have been set 
to the following (S7 is listed as well though it is still set to 
its nominal value): 
 
wire   nominal     now 
----   --------   ----- 
 S7A     2746     2746 
 S8A     2756     2650 
 S9A     2767     2530 
S10A     2773     2650 
S11A     2804     2770 
 
 
After 50 minutes, we have had 3 spikes.  So far so good.</pre>
<!-- Author: Kevin and Morris -->



<!-- Date: Fri Dec 19 13:27:39 2003 -->
<p>We have the following data available.  We have cosmic ray data taken with tranformers on SL7_S6b and SL7_S8b.  These are runs 176446 and 176480 taken Monday, December 15th.  The event displays indicated that the discharges were in cell_29, quadA for S6 and cell_245, quadC for S8 (exact cell number according to Bob).  </p>  
<p>During store 3101 on Wednesday, December 17th the transformers were moved to SL7_S7b and SL7_S9b.  During run 176576 there were about 100 events with a spike trigger.  These events all indicated discharges consistent with cell_29 and cell_245.  It is difficult to tell which wire is associated with which cell and in fact these two wires may be bad in both cells.  The presumption is that S9 is primarily bad in cell_29 and S7 is bad in cell_245.</p> 
<p>When we tried to start data taking for the record store 3103 on Thursday afternoon December 18th, the discharge problem got much worse for S9.  By switching the two HV current transformers to S9a and S9c, we were able to determine that the primary problem was in quadrantA.  There should be data to that effect in run 176623 that was taken while the transformers were still on S7b and S9b.  I have not had a chance to carefully look at these event, but presumably most are consistent with cell_29 in quadA.  However, note that overnight we got a few discharges on the quadC transformer whose sign indicated that the discharge was on S9c.  Probably, these are associated with cell_245, but futher checking is necessary.</p>
<!-- Author: Morris -->


<!-- Date: Mon Dec 22 21:40:47 2003 -->
<p>Today SL7_cell28 and SL7_cell246 were HV disabled.  When doing the capacitance test before removing the HV daughter boards, we found that cell28_S8 had a high capacitance reading of 7.8nf instead of the nominal 5.6-5.8nf.  Cell246_S8 had an 8.2nf reading and cell246_S9 had a 8.1nf reading, nominal again 5.6-5.8nf.  These are the same three wires for which Dave had found evidence for non-connectivity.</p> 
<p>For cell28, we tied S6, P7, S7, P8, S8, P9, S9, P10, S10, P11, and S11 to P12.  For cell246, we tied S7, P8, S8, P9, S9, P10, S10, P11, and S11 to P12.  Cell28 had HV daughter board #2432 and Cell246 had HV daughter board #0785.  When the boards were reinserted in the motherboard, the following capacitances were measured:  Cell28: P0-P6~2.5nf; P7-P11~2.7nf; P12=6.1nf; S0=5.9nf; S0-S5~5.7nf; S6-S11~8.5nf.  Cell246:  P0-P7~2.5nf; P8-P11~2.7nf; S0-S6~5.8nf; S7-S11~8.7nf.</p> 
At about 18:50 N2 flow to the baggie was set to 480scfh for each side.  At about 19:30, the O2 level was well below 2%, and Procedure 13 was started.  At about 19:45 full gas flow was initiated to the COT.  The initial O2 level was measured to be about 90ppm.  Dave checked the readout system and found no new problems.  In addition he had fixed one noisy ASDQ.  We had a flamable gas alarm due to operator error when removing the COT alarm override and had to reset the PC and all the low voltages. Flow to the GMC will be reset tomorrow.  Aseet will check the HV when he is in latter tonight.  If successful, he will notify silicon so they can begin cooldown.
<!-- Author: Morris, Aseet, Kevin, Dave, Wojciech -->


<!-- Date: Tue Dec 30 11:31:34 2003 -->
Until early yesterday morning there had been no spike triggers.  Then starting at about 01:14:32 on 29December there were apparently two flurries of triggers.  At almost the same time there was also a SL2_S6_OC trip (01:14:33).  The second flurry of spike triggers was at 01:17:14.  The digital scope trace for this flurry suggests that there was a large noise burst.  The length of the pulse was too short for a proper discharge which should have a decay constanst of 30-40usec.  
<!-- Author: Morris -->


<!-- Date: Tue Dec 30 11:33:26 2003 -->
<table><tr><td><a href=/elog/notebooks/cot/Tue_Dec_30_2003_113308.ps align=top><img src=/cgi/elog/det-system-elog.pl?nb=cot&action=view&page=-171  align='top'></a></td><td>Here is scope trace for the last flurry of spike triggers.</td></tr></table>
<!-- Author: Morris -->


<!-- Date: Fri Jan 2 11:12:25 2004 -->
<pre>We finally got 2 COT spike triggers that look real.  They came during the store that started about noon on New Years Day.  They both were on SL7_S8b.   The first happened at 15:14, but no data was being taken because or DAQ problems.  The second happened at 00:06 during Run 177267.  The scope trace looked like a real discharge.  I saved it to floppy, but there was a read error when I tried to read it out to put on my computer.  There were 4 events generated and they are in my cottrip area on fcdfsgi2 in run177267d.dat  A quick look suggests it is about cell 107 or 108, i.e. the last cells in quadrant a.  </pre>
<!-- Author: Morris -->


<!-- Date: Fri Jan 2 16:02:54 2004 -->
<pre>	Morris kept the spike trigger on SL7 S8b and S9b, such that it would  
 
trigger on discharges in any quad besides b.  He got 4 spike triggers on S8b  
 
(1/2/04) and stripped the events to ~binkley/cottrip/run177267d.dat.  The first 3  
 
spike events were centered on cell 107, the last cell in quadrant A.  The 4th  
 
event was consistent with cell 107.  This time I ran the file with YMon to verify  
 
that the cell number determined by counting from the quadrant boundary in evd was  
 
the correct number.  
--&gt;The first event was a "few-cell" blast centered on cell 107.  107-S7,S8 were  
 
empty ("eye") and S6 and S9 had multiplicity = 8. 
--&gt;The 2nd event was a megablast with a clear "eye" at 107-S8.  Again S7 and S8  
 
were empty. 
--&gt;The 3rd event was a megablast centered at cell 107.  107-S8 had the widest hit  
 
in the area. 
--&gt;The 4th event was a megablast consistent with beging centered at cell 107.   
 
	Dave may wish to see if he sees anything odd with the S8 or S7 calibration  
 
in cell 107. 
 
</pre>
<!-- Author: R. Wagner -->


<!-- Date: Sat Jan 3 10:25:40 2004 -->
<pre>	In the store beginning on 1/2/04, we got another two SL7 8b spike triggers in the first 16 hours at 1/2/04 18:39:36 and 1/3/04 07:15:48.  There was no run going during the first spike.  The second spike occurred during run 177314 and 3 MONITOR_SPIKE_COT triggers were recorded.  Morris' new program for stripping the spike triggers from the A (Express) stream is morrisacd.tcl, and the command lines are found in script.txt.  The events are in /cdf/data08/look/aphysr/ar02b4a2.048fphys. 
--&gt;The first event is a "few-cell" blast centered on cell 107.  Again 107-S7,S8 are both empty ("eye") and S6/S9 have max multiplicity. 
--&gt;Second event: Cell 107 is center of megablast, with S7 and S8 again empty. 
--&gt;Third event: Cell 107 is center of megablast.  107-S8 has by far the widest hit near the center. 
</pre>
<!-- Author: R. Wagner -->


<!-- Date: Mon Jan 12 11:06:58 2004 -->
Removed all extra supplies.  SL7 S7-S10 (of which only S9 and S10 were in use), and SL2 S5 (split for up/down current measurement).  Previous HvDefaults.dat renamed to HvDefaults12Jan04.dat. 
 
All three transformers remain hooked up as before, to SL7 S7-S9, all on quad. B, all in the "forward" direction (trigger on quadrants other than B).
<!-- Author: Aseet Mukherjee & Bob Wagner -->


<!-- Date: Wed Jan 21 14:21:41 2004 -->
<pre>There was a trip in SL1 and SL2 due to a spike in pbar losses (both in-time and abort gap).  All of our scalars also registered counts.  Some details: 
--&gt;In SL1 13:39:58 Trip SL1 S7 Oc 
--&gt;In SL2 13:39:58 Trip SL2 S3 SOc 
The scalar entries were at 13:39:57 (SL7 S7, S8, S9) (not quad B).  These looked like noise pulses. 
    There were &gt;300ua spikes on SL1 S0, S4, S7 and S11.  Visible, but less than 50 ua spikes, were seen on SL2 S0, S4, S5, and S7.</pre>
<!-- Author: R. Wagner and M. Binkley -->


<!-- Date: Fri Jan 30 16:47:36 2004 -->
<pre>Starting 1/30/04 and until further notice, please follow these instructions for operating the COT High Voltage: 
 
 
When a store ends or will end:  
 
1.	Set the COT High Voltage to OFF instead of STANDBY. 
 
2.	Call Morris Binkley (319-0039).  He will come in and modify some Superlayer 2 channels to run at -100 volts.  If you know in advance when the store will end, a heads up to Morris would be appreciated. 
 
 
"Before" the next store (At the start of shot setup on Day and Eve shifts; At the beginning of final proton injection on Owl shift): 
 
1.	Call Morris to come in and restore SL2 to its normal configuration.  If you can't reach Morris, call Aseet (399-1447).  Try their other numbers if you fail to make connection to the cell phones.  After restoring SL2, Morris (or Aseet) will set the COT to STANDBY. 
 
2.	After scraping is complete, turn the High Voltage from STANDBY to ON as usual. 
</pre>
<!-- Author: Bob Wagner, Morris Binkley, Aseet Mukherjee -->


<!-- Date: Mon May 17 20:48:33 2004 -->
 
<pre> 
Is there some other place I should be looking to learn what was done on today's access aside from here and the main CDF elog? 
 
-Ben Brau 
 
bbrau@fnal.gov 
</pre>
<!-- Author: bbrau -->


<!-- Date: Wed May 26 08:41:54 2004 -->
<pre>======================================================================== 
SL7-S2 trip 
======================================================================== 
16:46:05    25May    Run 183130    event 3336150 SL7-S2 tripped (I believe OC) 
Note that all scalars (SL7-S7, S8, S9. "not quad b") fired 1 second before the trip was recorded.  This should be the last "set" of discharge triggers for this run (the run was ended after the trip). Note that the last stream A file for this run is: 
 
May 25 17:20 /cdf/data08/look/aphysr/ar02cb5a.019dphys 
 
***** Closing output file: run183130.dat 
***** after 6 records, with a total size of 871kBytes written. 
***** 4 of those records were phyics events,  
***** whose average size is: 217kBytes/event 
 
Using 5.3.1 and evd_COT_2.tcl on fcdflnx3/home/wagner, I looked at events 3336147 to 3336150.  There was nothing obvious in SL7, including at cell 107 (source of the SL7-S8b discharge triggers in January). 
 
I took a closer look at the events for anything odd looking.  In the middle two events, cells 228 and 229 in quad C had clearly non-beam related hits: 
-&gt;3336148: Wide noise hits S2 - S5 in cells 228 and 229.  For S2, cell 229 had widest hit. 
-&gt;3336149: Narrow width hit way before t0 (maybe 100ns) in S2 for cell 229.  S3 has an early zero width hit in 229 and 228.  S4, S5 and S6 have early narrow or zero width hits in cell 228.     
</pre>
<!-- Author: R. Wagner -->


<!-- Date: Thu Jun 3 16:03:33 2004 -->
<pre>	There was another problem with flow through the alcohol bubbler on 6-1-04, again due to the pressure across the cold trap (this time #2 not #1) getting too high. 
 
Tue Jun 1 14:45:07 cot alarm on low flow limit to the alcohol bub supply side reading 13.42, set for 13.92 - Dean 
-- Tue Jun 1 15:51:07 comment by...Dean --  the alarm on the cot bub flow was linked to the cold trap #2 high differential pressure in the cold trap 
 
The lower flow should have only lasted about an hour, so the effect on the COT gas mixture should be small.  The Cold Trap pressure differential limit was again adjusted downward, this time from 14.8 to 14.3 psi.  Hopefully this will be enough to eliminate future problems.   </pre>
<!-- Author: R. Wagner -->


<!-- Date: Mon Jun 7 12:34:55 2004 -->
<pre>08:13:49 07 Jun (2004). SL7-S2-Oc Trip.  There were two SL7-S2 Scalar 
updates at the same time.  Run 183762 Event 3134304 at 08:13:55. 
 The shift crew tried to bring it up and it tripped on ramp.  The actual 
recorded channel was P1-SOc, but from later trips, S2 was also red.  The 
next time, I ramped up SL7 while observing the layer.  Ramping from 60 
to 80%, we got another trip recorded as P1-SOc, but S2 was red (Oc). 
About 1/2 second before the trip, S2 started sinking current and I did 
not observe the spike that caused the trip.  While sinking current, the 
S2 voltage was decreasing.  No other channels in SL7 appeared abnormal 
(some were still tuning at 80%). 
 At that point, the SL7-S2 pod was swapped with one from channel 7 in 
the neighboring auxiliary module.  The screw on the upper left hand 
corner was missing from the module, but the module seated well and was 
flush with the neighbor.  After powering up, the channels in the module 
looked fine (voltage and current draw) up to 10%.  Between 10 and 40%, 
all channels started mis-behaving.  SL7-S1 started sinking current 
first, followed by the other sense wires in the pod within the next 1/2 
second.  The layer eventually tripped on a spike following sinking 
current in S3.  At this point Aseet was consulted, and he indicated that 
that this behavior may be do to a bad 12 V connection to the module. 
The 12 volts provides the high voltage power. 
 We moved all pods from this module into a spare module, which had no 
screws.  Aseet transferred screws from the existing module, but this 
time left out the one in the upper right hand corner (which does not 
align with the connectors on the backplane).  The upper left hand hole 
in the crate was not stripped and the screw went in well.  The entire 
superlayer was brought up to full voltage with no problem.  Morris 
measured the Crate 4 AC ripple on the +/-12 V and -5 V at full load.  It 
was 2.0  mV on both 12 V and 2.8 mV on the -5V.  These were comparable 
to crate 5. 
 Would the original module for SL7-S2 have worked if we put the screw in 
the upper left hand corner?  As stated earlier, the module was well 
seated even without this screw, so at best it may have improved the 
seating by a very tiny amount.  There is nothing obviously amiss with 
the pins on the original module.  I will try to find a source of screws 
for replacing missing ones in modules.  I believe it may be best to send 
the original module to Prep for checkout under full load. 
 
-&gt;Original pod in SL7-S2: SN299, Fermi# 553022. 
-&gt;Pod now in SL7-S2: SN211, Fermi# 547029 
-&gt;Module (BiRa 4877) originally in SL7 P1-S4: Fermi# 546463 
</pre>
<!-- Author: R. Wagner, K. Burkett, M. Binkley, A. Mukherjee -->


<!-- Date: Thu Aug 12 12:49:06 2004 -->
<pre>Changed the QEN values (dE/dx enable) for SL1,3 from 0mV (dE/dx 
enabled) to 3500mV (dE/dx off) in the database.  These values 
will hold for the next store (last store was #3723).  The purpose 
is to investigate hit pile-up and tracking efficiency.</pre>
<!-- Author: ambrose -->


<!-- Date: Thu Aug 12 12:51:25 2004 -->
<table><tr><td><a href=/elog/notebooks/cot/Thu_Aug_12_2004_125105.ps align=top><img src=/cgi/elog/det-system-elog.pl?nb=cot&action=view&page=-173  align='top'></a></td><td>comparing widths from calibration pulses with and w/o 
the dE/dx function (QEN).  Width decreases about 25% 
after turning off dE/dx.</td></tr></table>
<!-- Author: ambrose -->


<!-- Date: Mon May 1 11:57:26 2006 -->
<table border=0><td><tr><td bgcolor=#e0e030><pre>bad TDC's:  
 
 
 
LE) b0cot19:Messenger:11:36:48 AM-&gt;TDC in slot 7, ID PROM not found (blank check)  
(MLE) b0cot19:Messenger:11:36:48 AM-&gt;Resetting card in slot 7 failed  
(MLE) b0cot19:Messenger:11:36:48 AM-&gt;TDC in slot 7 Toggle of event mask failed : 0xffffffff  
(MLE) b0cot19:Messenger:11:36:48 AM-&gt;TDC in slot 7, found DspVer=255, expected 68  
(MLE) b0cot19:Messenger:11:36:48 AM-&gt;Wrong TDC boardType: found 15, expected 9 in slot 7  
(MLE) b0cot19:Messenger:11:36:48 AM-&gt;Resetting card in slot 7 failed  
(MLE) b0cot19:Messenger:11:36:48 AM-&gt;Statechange failed  
(MLE) b0cot09:Messenger:11:36:49 AM-&gt;TDC in slot 15, ID PROM not found (blank check)  
(MLE) b0cot09:Messenger:11:36:49 AM-&gt;Resetting card in slot 15 failed  
(MLE) b0cot09:Messenger:11:36:49 AM-&gt;TDC in slot 15 Toggle of event mask failed : 0xffffffff  
(MLE) b0cot09:Messenger:11:36:49 AM-&gt;TDC in slot 15, found DspVer=255, expected 68 
 
 - Sasha Golossanov :: (run 215205) 
-- Mon May 1 11:46:52 comment by...Sasha G. --   
 
mark  b0cot19 TDC in slot 7 
      b0cot09 TDC in slot 15 
 
offline. </pre></td></tr></td></table>
<!-- Author: Sasha Golossanov -->