Difference between revisions of "Minutes-3-21-2013"

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(Created page with "March 21, 2013 FDC meeting = Agenda = # Production [http://www.jlab.org/Hall-D/detector/fdc/production/FDC_Construction_March_21_2013.xlsx Construction Tracking] (Dave) #* Spare...")
 
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= Agenda =
 
= Agenda =
 
# Production [http://www.jlab.org/Hall-D/detector/fdc/production/FDC_Construction_March_21_2013.xlsx Construction Tracking] (Dave)
 
# Production [http://www.jlab.org/Hall-D/detector/fdc/production/FDC_Construction_March_21_2013.xlsx Construction Tracking] (Dave)
#* Spare parts
 
 
#* Package #3 repair
 
#* Package #3 repair
 
# Installation [http://www.jlab.org/Hall-D/detector/fdc/procedures/FDC_install4.jpg schedule](Lubomir)
 
# Installation [http://www.jlab.org/Hall-D/detector/fdc/procedures/FDC_install4.jpg schedule](Lubomir)
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#* Cooling manifold installation and tests
 
#* Cooling manifold installation and tests
 
# Electronics (Chris, Nick)
 
# Electronics (Chris, Nick)
# Tests at EEL126 [https://halldweb1.jlab.org/elog-halld/FDC FDC E-log] (Beni)
+
# Tests at EEL126 [https://halldweb.jlab.org/elog-halld/FDC FDC E-log] (Beni)
 
# Other
 
# Other
  
<!--
 
  
 
= Minutes =
 
= Minutes =
  
Participants: Bill, Chris, Nick, Simon, Beni, and Lubomir.
+
Participants: Fernando, Eugene, Bill, Dave, Chris, Nick, Simon, Beni, and Lubomir.
  
 
== Production ==
 
== Production ==
  
- Dave (not at the meeting) prepared the Production Tracking: all cathodes for the spare package are ready. We will built also one extra cathode that is tensioned now. Wire planes: Chris is coming tomorrow to Blue Crab to finish with the population of the last two wire planes. Then it will remain four wire planes (one will be extra spare) to be deadened and we are done with the spare parts.    
+
- Dave: the last two wire frames populated by Chris. The only remaining operation is to deaden four wire planes. The extra spare cathode type-2 is tensioned, but the cards are not installed yet by purpose (for easy storage).
  
- On Friday package #1 was moved from 126 to Blue Crab and then package #2 - from Blue Crab to 126. After connecting #1 to Nitrogen it was found cell #5 is leaking; turned out the barb connector for the guage tube was loosely connected. These connectors are glued initially with super glue, but later on some of them (and not on this one) green epoxy was added. Casey was able to glue a new barb connector (not easy to reach the spacer ring  since you have only 5mm between the cathode and the wire frame) and fixed the problem. Then green epoxy was added on all the connectors of packages #1 and #4 that didn't have it before (5 out of 12). Bill wants to try with Casey using shoe glue that better sticks to polyethylene.  
+
- Package #3 repair: last Friday we started testing the top cell (after we opened it once and removed a lint) and it was tripping again. On Monday we opened the package for a second time and looked more carefully: there were some small balls on two sense wires and a section of a field wire that looked suspicious. We tried to clean these places and closed the package, turned out again without success. Troubleshooting the problem is difficult because it appears from time to time once per several hours. The dark currents are very low, there's no constant noise  and we can't localize the problem. We decided to open the package tomorrow morning, put the wire frame on the stringing table at 90deg (Bill's idea) and scan the wires with the camera. We will clean if possible, or replace the bad wires and next week will give it another try. If it still doesn't work, we will put a spare wire frame (#28, it had higher dark (~350nA) current but was stable for weeks).
  
- Package #3 repair: on Tuesday hubs were installed on the top side and the package put upside down on the installation table. To access cell #6 we had to remove only the end window and the bottom cathode (type-3). We found 1-2mm hair/lint on a field wire in HV sector 2, exactly where the HV problem was. After removing it we closed the package and started flushing it. It took only 4 people for two hours for this operation, but placing back the ground clips, pre-amps, cooling tube (all had to be removed) and restoring the HV connections will take much longer. The plan is to start testing the package tomorrow.
+
== Installation ==
  
- Pictures on the copper side of the cathode type-3 from package #3 are linked above. There's again some discoloration in the area that sits against the G10 of the wire frame. We had this when keeping the cathode moist over night when we started the production. One can see the G10 fiber pattern, so the explanation could be that some moisture got trapped there, most likely when there were AC problems in 126; this package was there for many months before the two new AC units were installed. From previous experience we know the copper is still conductive even it changes color.
+
- The last, "frozen" schedule moved the FDC installation just by a couple of days. Now the FDC insertion is in the middle of January 2014, dictated mainly by the electronics. Since the testing outside of the magnet should start much earlier we must be able to test the different packages connecting to the same electronics.  
  
== Installation ==
+
- With Eugene, Bill, and Fernando together there were long discussions about the cabling. There was a concern (Lubomir) that with the current installation scheme, when the FDC is inserted one needs extra cable that is one cart long. In total we will need about 3 x 2.5 carts which might be close to 18m, the length of the signal cables. Bill will check that with the I-deas model. Fernando insisted that we have to keep the cables fixed to the racks at the downstream end and never un-bundle them. In this case the question is where to put the extra bundles that are 6-7m long after the insertion of the FDC: if possible somewhere at the front of the magnet??
  
- This week there were significant changes in the re-baselined schedule. The last- and this-week-schedule related to the FDC installation are linked above. Almost all of the FDC installation activities are delayed by 1-2 months, so the insertion into the magnet happens in the beginning of January 2014. From Eugene we know the big change is a result of a manpower spike that had to be smooth out. Beni: if this is the case probably additional manpower from the universities could help. However, Beni learned from Fernando the real reason is the the timing of the receiving of the fADC125 and F1TDC, and their testing/installation in the crates and racks and here students could not help. Expect more discussions in the coming meetings.
+
- Installation of the cables from the two bottom quadrants will be difficult because of the small opening going to the bottom (below the platform) trays. Bill had an idea to elevate the racks so that the space below them will be accessible from the front and the cables can run there. This makes the cable installation much easier, but requires taller people to service the electronics. Other options: 1) disconnecting the cables from the electronics before FDC insertion and re-connecting them again after the insertion (Lubomir), but has to be done every time we take FDC out of the magnet. 2) Putting all the cables on the top side of the racks (Eugene), but the length might not be enough and it will be more difficult to work there.
  
- In this case the chance that we will have to leave Blue Crab but the infrastructure in the Hall will not be ready for the FDC installation, is very big. According to Rusty Sprouse the plan for Blue Crab is to extend  the lease by one month (till the end of September), but has not been done yet. In the best base we will have to leave end of August, but the installation will start in October according to the new schedule, so we need to find a storage space. ESB has climate control but is very dirty. Bill: what about space in TDEF? Beni: can we move the clean room (or part of it) from Blue Crab to the ESB?
 
 
 
== Engineering ==
 
== Engineering ==
  
- Bill and Casey finished the manifold installation on package #4. Bill explained details of the procedure using the pictures linked above. Next step is to do tests with pressured gas at Blue Crab. For the rest of the packages, Bill has to do some modifications on the plastic brackets that are used at the 210deg manifold.
+
- Bill and Casey tested the cooling of package #4 that has the manifolds installed: first with CO2 at 100psi and then with Flurinert, pressured again with CO2. No significant leakage was found with CO2, but with Flurinert it was leaking like a sieve (Bill) however mostly at the temporary barb connections needed to do the test, while the compression connections didn't show obvious problems. It turned out the leakage detector we have is not very sensitive to Fluorinert. So, for the next test we need better fittings and leakage detector. 
 +
 
 +
- Bill ordered three more manifold (Norel material), because three were damaged during the installation. Bill also ordered new G10 pieces that are needed to hold the tubes at the 210deg mounting place.
 +
 
 +
== Electronics ==
 +
 
 +
- Fernando: we have already 16 fADC125 and Cody is testing them. Some delays in this pre-production and the procurement is helping to accelerate it.
  
 
== Tests at EEL126 ==
 
== Tests at EEL126 ==
  
- Beni showed HV and threshold scan of package #1 (entry 107 in the FDC E-log). There were some problems in some of the runs at lower HV, but in general the plateau starts at 2050V for 5V threshold and at 2100V at 7V. Beni went up to 2200V and the HV was stable.
+
- Beni at the beginning of the meeting showed results from the tests of the last production package (#2): entry 108 in the FDC E-log. All the channels without any exceptions are working fine. One of the HV connectors (from the side of the detector) had some issues, but was connected. 
 +
 
 +
- The plan is to start preparing for the tests with the full electronics. For this tests, Beni's plan (not present at these discussions) is not to read all the samples, but to have the charge integration and timing extraction done in the ROCs. Eugene: what is the advantage of this compared to just writing all the samples to the disk and later do this off-line. Obviously, writing and reading the files will take much more time, but Beni may have better explanation. As for the cooling Bill says it must be ready in few weeks. A water chiller will be borrowed from FEL, instead of repairing the one they offered us before.
  
- Package #2: Beni already tested the strips of four cells and all the wire channels (except few with noisy electronics) and all channels were OK.
+
== Other ==
  
-->
+
- NO FDC meeting next week.

Latest revision as of 06:20, 1 April 2015

March 21, 2013 FDC meeting

Agenda

  1. Production Construction Tracking (Dave)
    • Package #3 repair
  2. Installation schedule(Lubomir)
  3. Engineering (Bill)
    • Cooling manifold installation and tests
  4. Electronics (Chris, Nick)
  5. Tests at EEL126 FDC E-log (Beni)
  6. Other


Minutes

Participants: Fernando, Eugene, Bill, Dave, Chris, Nick, Simon, Beni, and Lubomir.

Production

- Dave: the last two wire frames populated by Chris. The only remaining operation is to deaden four wire planes. The extra spare cathode type-2 is tensioned, but the cards are not installed yet by purpose (for easy storage).

- Package #3 repair: last Friday we started testing the top cell (after we opened it once and removed a lint) and it was tripping again. On Monday we opened the package for a second time and looked more carefully: there were some small balls on two sense wires and a section of a field wire that looked suspicious. We tried to clean these places and closed the package, turned out again without success. Troubleshooting the problem is difficult because it appears from time to time once per several hours. The dark currents are very low, there's no constant noise and we can't localize the problem. We decided to open the package tomorrow morning, put the wire frame on the stringing table at 90deg (Bill's idea) and scan the wires with the camera. We will clean if possible, or replace the bad wires and next week will give it another try. If it still doesn't work, we will put a spare wire frame (#28, it had higher dark (~350nA) current but was stable for weeks).

Installation

- The last, "frozen" schedule moved the FDC installation just by a couple of days. Now the FDC insertion is in the middle of January 2014, dictated mainly by the electronics. Since the testing outside of the magnet should start much earlier we must be able to test the different packages connecting to the same electronics.

- With Eugene, Bill, and Fernando together there were long discussions about the cabling. There was a concern (Lubomir) that with the current installation scheme, when the FDC is inserted one needs extra cable that is one cart long. In total we will need about 3 x 2.5 carts which might be close to 18m, the length of the signal cables. Bill will check that with the I-deas model. Fernando insisted that we have to keep the cables fixed to the racks at the downstream end and never un-bundle them. In this case the question is where to put the extra bundles that are 6-7m long after the insertion of the FDC: if possible somewhere at the front of the magnet??

- Installation of the cables from the two bottom quadrants will be difficult because of the small opening going to the bottom (below the platform) trays. Bill had an idea to elevate the racks so that the space below them will be accessible from the front and the cables can run there. This makes the cable installation much easier, but requires taller people to service the electronics. Other options: 1) disconnecting the cables from the electronics before FDC insertion and re-connecting them again after the insertion (Lubomir), but has to be done every time we take FDC out of the magnet. 2) Putting all the cables on the top side of the racks (Eugene), but the length might not be enough and it will be more difficult to work there.

Engineering

- Bill and Casey tested the cooling of package #4 that has the manifolds installed: first with CO2 at 100psi and then with Flurinert, pressured again with CO2. No significant leakage was found with CO2, but with Flurinert it was leaking like a sieve (Bill) however mostly at the temporary barb connections needed to do the test, while the compression connections didn't show obvious problems. It turned out the leakage detector we have is not very sensitive to Fluorinert. So, for the next test we need better fittings and leakage detector.

- Bill ordered three more manifold (Norel material), because three were damaged during the installation. Bill also ordered new G10 pieces that are needed to hold the tubes at the 210deg mounting place.

Electronics

- Fernando: we have already 16 fADC125 and Cody is testing them. Some delays in this pre-production and the procurement is helping to accelerate it.

Tests at EEL126

- Beni at the beginning of the meeting showed results from the tests of the last production package (#2): entry 108 in the FDC E-log. All the channels without any exceptions are working fine. One of the HV connectors (from the side of the detector) had some issues, but was connected.

- The plan is to start preparing for the tests with the full electronics. For this tests, Beni's plan (not present at these discussions) is not to read all the samples, but to have the charge integration and timing extraction done in the ROCs. Eugene: what is the advantage of this compared to just writing all the samples to the disk and later do this off-line. Obviously, writing and reading the files will take much more time, but Beni may have better explanation. As for the cooling Bill says it must be ready in few weeks. A water chiller will be borrowed from FEL, instead of repairing the one they offered us before.

Other

- NO FDC meeting next week.