Difference between revisions of "Minutes-1-19-2012"

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# Production [http://www.jlab.org/Hall-D/detector/fdc/production/FDC_Construction_January_19_2012.xlsx Construction Tracking] (Dave)
 
# Production [http://www.jlab.org/Hall-D/detector/fdc/production/FDC_Construction_January_19_2012.xlsx Construction Tracking] (Dave)
 
#* Production update
 
#* Production update
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#* First package cabling
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#* First package cabling [http://www.jlab.org/Hall-D/detector/fdc/pictures/Dsc06946_2.jpg], [http://www.jlab.org/Hall-D/detector/fdc/pictures/Dsc06957_2.jpg]
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# Engineering update (Bill)   
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# Engineering update [http://www.jlab.org/Hall-D/detector/fdc/wire_deadening/Lrg-dia_w1_x1000_edge-3d.jpg new diameter wire deadening],[http://www.jlab.org/Hall-D/detector/fdc/wire_deadening/Lrg-dia_w1_x1000_center1-3d.jpg]  (Bill)   
 
# Electronics update (Chris)
 
# Electronics update (Chris)
 
#* Pre-amp cards
 
#* Pre-amp cards
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# Testing in 126 (Beni)
 
# Testing in 126 (Beni)
 
# Other
 
# Other
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<!--
 
  
 
= Minutes =
 
= Minutes =
  
−
Participants: Bill, Dave, Chris, Mark, Simon, Beni, and Lubomir.   
+
Participants: Bill, Dave, Chris, Simon, Beni, Eugene, and Lubomir.   
  
 
== Production ==
 
== Production ==
  
−
- Dave: second package ready, working now on the third. First wire frame strung today, two end windows and one type-1 cathodes ready, working on two type-3 cathodes and started type-2. Dark current was tested on the PCBs for the next wire frame (we are doing this test now both before and after frame lamination).
+
- Dave: working on the first cell of the third package. Wire frame was strung, but two field wires (next to each other) showed lower tension (106g instead of 130g nominal, but actually mean measured value is around 120g) and were replaced. Could be because of local frame deformation so that wires are touching the board with some friction, so when raising the wire frame try not to touch the wires. Could be also some garbage on the pulley or on the rod. One type-1 cathode is ready, two type-3 waiting for the daughter cards to be glued. Wire frame for the second cell is ready for stringing.
  
−
- The thick copper tube that was put on two cells of the first package was removed. Today we received the thinner tube that will be installed on all the cells. Dave and Anatoly labeled the HV connectors. Fernando and Chris will come next Tuesday to do the HV connections, by that time we should be ready with the cooling tubes.
+
- Testing wire deadening with new diameter for the last two packages: Bill recalculated the currents/timing and one sample was made. It turned out the surface looks more rough that before (see microscope picture attached). Bill will add another electro-polishing cycle to smooth the surface and will try it on another sample.
  
−
- Tooling needed for the installation of the third package: we will re-use half of the hubs from the first two packages. Bill asked if we need new transfer ring: no. Beni talked to Roger: do we need more foils from Allflex, no; what should we do with the extra foil material at Minnesota, should be shipped to us.
+
- All the pre-amp cards and cooling tubes were put on the first package. All HV cables were routed on the package and Chris made the connections to the HV connector (see attached pictures). All positive HV cables are bundled on the upper side of the package and all the negative HV run on the down side. To help the installation the package was installed on the supporting frame to allow its rotation.
−
 
+
−
- The last cell of the second package was installed on Friday and was tested this week successfully. Will flush it with gas till the beginning of the next week and do some more tests.
+
  
 
== Engineering ==
 
== Engineering ==
  
−
- Bill explained to us the latest ideas about FDC cabling: exoskeleton (Al mesh) will be attached to BCAL on 6(?) rails with cables running at the outer side, CDC will be inside. The exoskeleton will reach (and attached to) the first upstream package then the cables will be attached to the cooling tubes of the other packages. This may require additional attachment of of the cooling tubes to the frames, since now they are hold by the pre-amps only. There's a mock-up ready.
+
- We discussed how to run/attached the ground cable (0.5" thick!). There will be a copper plate on each package connecting together the ground cable with the detector ground and HV return cables. Bill needed the cable specs from Chris to do the design.
  
−
- The new copper tubes even thinner than the first: 0.5mm walls. The thick (1mm wall) tubes will be returned. The tool to hold the pre-amp brackets during tube installation was designed and will be ready for the installation.
+
- Bill is designing the tool for plugging the LV connectors and working also on the cooling system.
  
 
== Electronics ==
 
== Electronics ==
  
−
- Chris: all the pre-amps for the first package ready, now at Blue Crab. Each has serial number that should be entered in a look-up table with its position it the package. The extra set to be tested at the second package will be ready soon. Chris ordered the LV ERNI connectors needed for the 126 tests.  
+
- Chris: seven pre-amp sets (each 22 cards) are ready and installed on the chambers. Out of them maybe 4-5 cards were out of specs, but Cody would know this better. Chris just finished testing (during the meeting) 32 flat cables to be used between the translator boards and the TDCs for the package testing in 126. 4 more are needed. Will do also 17 LV cables for the tests. 14 of them will have 8 connectors for the cathodes and 3 with 4 connectors for the wires. Lubomir will specify the distance between the connectors.
  
−
- Bill wanted to know how many extra heat clamps are needed to be installed on the spare pre-amp. Chris will replay on this.
+
- Final LV scheme per package will have 6 cables with 2 connectors 3 inch apart for the wires, and two cable types for the cathodes with 4 connectors: type-1 6 inches apart and type-2 5-8.5-4 inches distance between
 +
connectors. Had to increase the distances by 1/2" from the nominal values due to the 1/2" precision that the company can do.
  
−
- Lubomir tested in place the new LV scheme using three types of cathode cables with the four connectors at distances of 4-4-4" (8pc per package), 7-4-4" (14pc),and 4-9.5-4" (5pc). These lengths take into account that cables may run outside of the cooling tubes. The cables will have different colors and the connectors have to be painted somehow as well. Bill suggested how to put additional labels on the LV connectors if needed. Connecting these at some places is tricky and Bill will design a tool for that.  
+
- Some questions that we had to discuss with Fernando about the anode cards. The discriminator cards as installed on the chamber, generate if the external threshold voltage is below 7-10V. According to GlueX Doc1470, this corresponds to about the maximum of the amplifier amplitude. The threshold at which the generation starts also may vary significantly from channel to channel on the same card.  
  
 
== Testing at 126  ==
 
== Testing at 126  ==
  
−
- According to Fernando if we have LV power to the pre-amps, the cathodes will be at low potential. This requires 27 LV cables, for that Chris will order also cables/wires. It's not clear what would the strip potential be if the pre-amps are not supplied. 
+
- Beni is missing three F1TDC to have all the wires read out. Other than that and the LV cables that Chris will do, everything is ready for the first package that we plan to move on Monday.
−
 
+
−
- Some progress with the multi-crate system, that we don't need right now.
+
−
 
+
−
== TDR ==
+
−
 
+
−
- Slow progress, Bill will make a beautiful picture of the cathode/wire frame positions within the package.
+
−
 
+
−
== Other ==
+
−
 
+
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- Many people were very happy with the FDC presentation at the Hall-D open house. Thanks to Dave for the organization, Mike for preparing the slide show and all the techs for participating in the event and sharing their experience with the others.
+
−
 
+
−
-->
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Latest revision as of 17:51, 19 January 2012

January 19, 2012 FDC meeting

Agenda

  1. Production Construction Tracking (Dave)
    • Production update
    • First package cabling [1], [2]
  2. Engineering update new diameter wire deadening,[3] (Bill)
  3. Electronics update (Chris)
    • Pre-amp cards
    • LV cabling
  4. Testing in 126 (Beni)
  5. Other

Minutes

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

Production

- Dave: working on the first cell of the third package. Wire frame was strung, but two field wires (next to each other) showed lower tension (106g instead of 130g nominal, but actually mean measured value is around 120g) and were replaced. Could be because of local frame deformation so that wires are touching the board with some friction, so when raising the wire frame try not to touch the wires. Could be also some garbage on the pulley or on the rod. One type-1 cathode is ready, two type-3 waiting for the daughter cards to be glued. Wire frame for the second cell is ready for stringing.

- Testing wire deadening with new diameter for the last two packages: Bill recalculated the currents/timing and one sample was made. It turned out the surface looks more rough that before (see microscope picture attached). Bill will add another electro-polishing cycle to smooth the surface and will try it on another sample.

- All the pre-amp cards and cooling tubes were put on the first package. All HV cables were routed on the package and Chris made the connections to the HV connector (see attached pictures). All positive HV cables are bundled on the upper side of the package and all the negative HV run on the down side. To help the installation the package was installed on the supporting frame to allow its rotation.

Engineering

- We discussed how to run/attached the ground cable (0.5" thick!). There will be a copper plate on each package connecting together the ground cable with the detector ground and HV return cables. Bill needed the cable specs from Chris to do the design.

- Bill is designing the tool for plugging the LV connectors and working also on the cooling system.

Electronics

- Chris: seven pre-amp sets (each 22 cards) are ready and installed on the chambers. Out of them maybe 4-5 cards were out of specs, but Cody would know this better. Chris just finished testing (during the meeting) 32 flat cables to be used between the translator boards and the TDCs for the package testing in 126. 4 more are needed. Will do also 17 LV cables for the tests. 14 of them will have 8 connectors for the cathodes and 3 with 4 connectors for the wires. Lubomir will specify the distance between the connectors.

- Final LV scheme per package will have 6 cables with 2 connectors 3 inch apart for the wires, and two cable types for the cathodes with 4 connectors: type-1 6 inches apart and type-2 5-8.5-4 inches distance between connectors. Had to increase the distances by 1/2" from the nominal values due to the 1/2" precision that the company can do.

- Some questions that we had to discuss with Fernando about the anode cards. The discriminator cards as installed on the chamber, generate if the external threshold voltage is below 7-10V. According to GlueX Doc1470, this corresponds to about the maximum of the amplifier amplitude. The threshold at which the generation starts also may vary significantly from channel to channel on the same card.

Testing at 126

- Beni is missing three F1TDC to have all the wires read out. Other than that and the LV cables that Chris will do, everything is ready for the first package that we plan to move on Monday.

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