Difference between revisions of "Minutes-1-12-2012"

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# [http://www.jlab.org/Hall-D/detector/fdc/tdr/tdr.pdf TDR] (Lubomir)  
 
# [http://www.jlab.org/Hall-D/detector/fdc/tdr/tdr.pdf TDR] (Lubomir)  
 
# Other
 
# Other
 
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= Minutes =
 
= Minutes =
  
Participants: Bill, Dave, Chris, Mark, Simon, Beni (ESNET), Eugene, and Lubomir.   
+
Participants: Bill, Dave, Chris, Mark, Simon, Beni, and Lubomir.   
  
 
== Production ==
 
== Production ==
  
- Dave for the last cell of the second package: a field wire was replaced on the wire plane yesterday to be cleaned today, daughter cards were glued on the type-2 cathode today, type-1 cathode is ready. Tomorrow we will have all the parts of the last cell ready for testing and installation. Next cell (for third package): wire frame was laminated, type-1 cathode ready, working on the flaps for the type-2 cathode. For the nex wire frame lamination we will use a board with the vias not sealed (we have several of this kind); Bill suggested using Hysol to cover the vias right after lamination.
+
- 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).
  
- The fifth cell of the second package was installed right before the break and was tested this week successfully. It took long time (~10 days) to condition the chamber: Epon didn't dry as usual or gas flow was too low during the break?
+
- 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 them time we should be ready with the cooling tubes.
 +
 
 +
- Tooling needed for the installation of the third package: we will re-use half of the hubs from both 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.
 +
 
 +
- 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 showed pictures for different parts of the cooling system: pump, manifold. The pump is supposed to operate at ~100psi. The coolant (Fluorinert) is heavier (1.73g/cm^3) than watter.
+
- 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.
+
- Cu tubing: by directly measuring the weight of a tube piece we found the tube is heavier than what was used in the simulations. Later it turned out that the tubing was simulated correctly, according to the specifications for the tube sizes: 4mm OD and 2.79mm ID. For 4mm OD and Cu density of 8.96 g/cm^3  from the weight measurements one gets 2.14mm ID. After the meeting direct ID measurements confirmed the specified 2.79mm. The only explanation so far is that the density of the tube material is higher.  
+
  
- We discussed if we need additional hubs and pins to assemble the last two packages, or we can re-use some of those from the already assembled packages. We need the hubs for the tests in 126 (to attach the strongback).
+
- 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.
  
 
== Electronics ==
 
== Electronics ==
  
- Chris: made 4 more pre-amp sets (22 each) for the remaining cells in the first package. Will do one more set to be installed on the second package for testing purposes. All the pre-amps will be tested by Cody and likely will have them next week.
+
- 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 will make the HV connections on the first package next week; before that we have to do the labeling.
+
- Bill wanted to know how many extra heat clamps are needed to be installed on the spare pre-amp. Chris will replay on this.
  
- Vlad came with a scheme for the cathode LV cables: three types with distances between the four connectors of 8-3-8, 6-3-3, and 3-3-3 inches.
+
- 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.  
In addition will have anode LV cables with two connectors 2.75" apart. We discussed how to label the connectors/cables to help their installation. Certainly color coding will be used for the different cable types, but we need also labels (difficult to be put on these connectors).
+
 
+
- Grounding: it turned out that measuring the resistance with probes directly on the pre-amp clamps (coated aluminum) gives strange results, but when we measured it between the Cu tubes and the pre-amp card it turned out to be practically zero. In this case the grounding with the Cu tube is an option that has to be tested in 126 and compared to the scheme when using separate ground clamps and wires/braided ground straps.  
+
  
 
== Testing at 126  ==
 
== Testing at 126  ==
 +
 +
<!--
  
 
- Beni asked if the flat cables for the translation cards are ready. Chris will work on them after he's done with the other stuff.
 
- Beni asked if the flat cables for the translation cards are ready. Chris will work on them after he's done with the other stuff.

Revision as of 17:59, 12 January 2012

January 12, 2012 FDC meeting

Agenda

  1. Production Construction Tracking (Dave)
    • Production update
    • First package cabling
    • Second package tests (Lubomir)
  2. Engineering update (Bill)
    • Copper tubing
  3. Electronics update (Chris)
    • Pre-amp cards
    • LV cabling (Lubomir)
  4. Testing in 126 (Beni)
  5. TDR (Lubomir)
  6. Other

Minutes

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

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).

- 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 them time we should be ready with the cooling tubes.

- Tooling needed for the installation of the third package: we will re-use half of the hubs from both 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.

- 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

- 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.

- 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.

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.

- Bill wanted to know how many extra heat clamps are needed to be installed on the spare pre-amp. Chris will replay on this.

- 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.

Testing at 126