Difference between revisions of "Minutes-7-5-2012"

From GlueXWiki
Jump to: navigation, search
(Created page with "July 5, 2012 FDC meeting = Agenda = # Production [http://www.jlab.org/Hall-D/detector/fdc/production/FDC_Construction_July_5_2012.xlsx Construction Tracking] (Dave) #* Productio...")
 
(Engineering update)
 
(22 intermediate revisions by the same user not shown)
Line 6: Line 6:
 
#* Fourth package tests
 
#* Fourth package tests
 
#* Refurbishment preparations
 
#* Refurbishment preparations
# Engineering update  
+
# Engineering update
#* Cooling system [http://www.jlab.org/Hall-D/detector/fdc/deneral/cooling.pdf Example of water cooling]
+
#* Cooling system [http://www.jlab.org/Hall-D/detector/fdc/drawings/Assembly1.png], [http://www.jlab.org/Hall-D/detector/fdc/drawings/Assembly2.png], [http://www.jlab.org/Hall-D/detector/fdc/drawings/Assembly3.png],[http://www.jlab.org/Hall-D/detector/fdc/drawings/Assembly4.png]
 +
#* [http://www.jlab.org/Hall-D/detector/fdc/general/cooling.pdf Example of water cooling]
 
# Electronics update (Chris)
 
# Electronics update (Chris)
# [http://www.jlab.org/Hall-D/detector/fdc/documents/preamp_position_in_racks.pdf Cable assignment] (Vlad)
+
# [http://www.jlab.org/Hall-D/detector/fdc/documents/FDC_LV_cable_assignment.pdf LV cable assignment] (Vlad)
 
# Test set-up in 126 (Beni)
 
# Test set-up in 126 (Beni)
 
# Other
 
# Other
 
<!--
 
  
 
= Minutes =
 
= Minutes =
  
Participants: Tom, Scott, Eugene, Tim, Slava, Mark, Dave, Chris, Nick, Vlad, Simon, Beni, and Lubomir.  Many participants this time, some of them left after Tom's presentation.
+
Participants: Bill, Glen, Eugene, Chris, Nick, Simon, Vlad, Beni, and Lubomir
 
+
== FDC installation and cable routing ==
+
 
+
- Tom went through the slides linked above showing the FDC in three positions and on separate slides only the cable routing for these positions. The cables are divided in four quadrants and bundled together between the mesh cylinder (that separates the cables from the CDC) and the electronics racks.
+
Left and right sides are symmetric. Two bundles run on the floor turn, below the platform, and go up through openings to the racks. The other two bundles will run over hangers attached to the racks and installation carts.
+
 
+
- The length of the bundles in the drawing is biggest for the initial position. While the FDC is being moved into the magnet, the top sections of the carts will be removed and the lower bundles will be lifted (there's enough slack) over the lower part of the carts. According to Tom this will be the most difficult part: the bundles have to be well supported to avoid deformation of the mesh cylinder. During this operation the bent position of the bundles will change all the time. Despite the stiffness of the bundle this will be possible (Tim, Tom). In the final position the length of the bundled section will be smallest, in reality the bundle length will not change, which means we have to find place for service loops. There will be additional loops of the individual cables either inside the bundles or close to the electronics.
+
  
 
== Production ==
 
== Production ==
  
- Dave: Installation of the fourth package was completed on Monday. Today Vlad noticed that one cathode in the middle was positioned incorrectly (15deg off). We discussed if it is possible to lift the top three cells together, correct the cathode position and then put the three cells back. For that we pull down the installation pins (one by one) to the right position so that separate only the top three cells and then insert from the top additional pins to keep to top part together. After the meeting this operation was done successfully. Three of the pins we did like this, for the other three we pushed the top pins further down so that it was easier to insert the top part in the right place.
+
- Dave was absent but he updated the production tracking linked above: last two spare cathodes are almost ready. Spare wire frames: third wire frame (#6) is being tested already for a week, the current is very high (~1100nA) which doesn't surprise anybody since the caps were not replaced. Bill wanted to know if we have to order additional g10 frames. We have one spare frame now that will be used to replace wire frame #1. First we will try to fix #6, if it doesn't work we have to order g10 frames. The problem with #6 is that the caps are covered with Himiseal. Bill suggested, first, removing the caps (say on one HV sector) and then cleaning the Humiseal. Chirs: aceton cleans Humiseal very well (we can't use it inside the chamber!), but one can also use alcohol; have to soak the Humiseal first and after 5min start cleaning. We will try that.  
We can use this technique to separate part of the package if we have to fix something there.  
+
  
- Dave showed the scheme (linked above) for the package refurbishment. As we did with the third and fourth packages we will install and test them in two halves. Techs working on the last two spare cathodes and preparing the last two spare wire frames for testing.  
+
- Started  preparations of the first package (which is at Blue Crab) for refurbishment: HV cables from the PCBs were disconnected from the cables that are in turn connected to the two HV connectors. Later we may have problems to reconnect them since the cables were cut to the proper length, we have to route them exactly as they were before. Copper tubes (together with one part of the pre-amp brackets that is glued to the tube) and the pre-amps were removed from the package.  
  
- Chris will submit PR for four PCB sets. We need to build (so far) one wire frame and for that we have a spare laminated G10 frame. If more wire frames are needed we will have to order more G10 frames, as well.
+
- Fourth package tests: Vlad tested cell #4 which is OK. On cell #3 (with wire frame #27) the current was very high (~800-1000nA) and doesn't go down already four days, but never tripped: most likely the HV caps have problems. Other than that all the channels on #3 are fine. Vlad applied today HV on cell #2 (wire frame #28), the current was initially 500nA but then started going up. It turned out Anatoly doesn't have a record that he had replaced the HV caps on #28. We will finished with the tests on cell #2 and cell #1 and then decide what exactly we want to disassemble.
 
+
- Today the first package was moved back from EEL126 to Blue Crab for refurbishment. We are preparing for the installation of the subsystems on the third package. Will try to print the pre-amp labels from file and put them on the cards before the installation.
+
  
 
== Engineering update ==  
 
== Engineering update ==  
  
- Eugene asked us before if we can use water for cooling instead of Fluorinert and if there are examples for that. At ATLAS all the cooling systems that are not serviceable use some type of Fluorinert, while for the outer system water cooling is used as well.
+
- Bill gave us some detail about the cooling system: ~2gal, 32psi, tubes outside of the packages are (special) plastic 3/4" ID, brass compression fittings, manifolds are made out of Norel, tubes on the packages are copper 2.79mm ID. Water or Fluorinert: Fluorinert is $500/gal but volume is only 2 gal; the main concern is about leakages and special pump and fittings that are needed. Water leakage can cause damages, need to cover BCAL and try somehow to cover the manifolds. It turned out at the LHC experiments there's only one example when water is used for cooling a detector that is not accessible: the ECAL for CMS. In this case, however, many additional systems are included (see text above) to monitor the pressure, temperature and flow and in case of leakage to separate sections of the system and evacuate the water from there. All at the meeting, including Bill and Eugene, think Fluorinert is a better choice.  
  
- We discussed what will happen in case of water leakage and if there's a way to put containers below the manifolds.
+
- Bill went through the drawings linked above, explaining the cooling system. There are two loops, inner and outer. The outer uses water. There's a heat-exchanger between the two loops. Beni and Eugene asked about its reliability, what is the pressure difference in the inner and outer loops. The cooling system cart is supposed to be placed on the floor downstream after the magnet, but Eugene suggested to keep this space empty for the future Cherenkov detector.
The main question, if it is safe to use water, remains. Certainly this has to be discussed with Bill and Fernando.
+
  
 
== Electronics update ==
 
== Electronics update ==
  
- Chris: delay with the grounding clips, they were supposed to be done by today, but the company answered they will send us first article sometimes next week. 
+
- Chris: no grounding clips yet. The sole source PR about the PCBs was returned to Chris: not enough reasons for the sole source. Chris will ask Fernando for help in formulating the sole source argumentation.
 
+
== Cable assignment ==
+
 
+
- Vlad: final scheme linked above. Same logic for distributing the loads within a package, but this time the packages are separated, i.e no mixture of cables from different packages.
+
  
== Gas system ==
+
== LV cable assignment ==
  
- Beni: Narciso has a preliminary scheme and scheduled a meeting beginning of next month.  
+
- Vlad: LV scheme is linked above, at the end of the file the cables are shown with the corresponding pre-amps and their labels for the cathodes: four pre-amps per cables. For the wires the cables are identified by the range of the channels on the PCB to which the LV cable is connected. We will put these lables on both sides of the LV cables.  
  
 
== Test set-up at 126 ==
 
== Test set-up at 126 ==
  
- Beni: working on CODA-Light for the two-crate system, will move to Linux ROCs. Eugene: why not to use real CODA?
+
- Beni: the configuration of the DAQ to be used with two new Linux ROCs is close to complete. Old TIs will be used for the FDC DAQ system.
  
- Vlad tested the cathodes of five cells (the 55Fe source is not strong enough for the sixth cell). All channels working, but same complains as before: need to fix the cooling tubes somehow to the chamber. We will attach them to the holes at the perimeter of the frames with cable ties. Problems with the pins of two LV connectors.
+
== Other ==
  
-->
+
- Beni: next Wednesday (7/11) at 10am there will be a meeting about the gas system.

Latest revision as of 11:46, 6 July 2012

July 5, 2012 FDC meeting

Agenda

  1. Production Construction Tracking (Dave)
    • Production status
    • Fourth package tests
    • Refurbishment preparations
  2. Engineering update
  3. Electronics update (Chris)
  4. LV cable assignment (Vlad)
  5. Test set-up in 126 (Beni)
  6. Other

Minutes

Participants: Bill, Glen, Eugene, Chris, Nick, Simon, Vlad, Beni, and Lubomir

Production

- Dave was absent but he updated the production tracking linked above: last two spare cathodes are almost ready. Spare wire frames: third wire frame (#6) is being tested already for a week, the current is very high (~1100nA) which doesn't surprise anybody since the caps were not replaced. Bill wanted to know if we have to order additional g10 frames. We have one spare frame now that will be used to replace wire frame #1. First we will try to fix #6, if it doesn't work we have to order g10 frames. The problem with #6 is that the caps are covered with Himiseal. Bill suggested, first, removing the caps (say on one HV sector) and then cleaning the Humiseal. Chirs: aceton cleans Humiseal very well (we can't use it inside the chamber!), but one can also use alcohol; have to soak the Humiseal first and after 5min start cleaning. We will try that.

- Started preparations of the first package (which is at Blue Crab) for refurbishment: HV cables from the PCBs were disconnected from the cables that are in turn connected to the two HV connectors. Later we may have problems to reconnect them since the cables were cut to the proper length, we have to route them exactly as they were before. Copper tubes (together with one part of the pre-amp brackets that is glued to the tube) and the pre-amps were removed from the package.

- Fourth package tests: Vlad tested cell #4 which is OK. On cell #3 (with wire frame #27) the current was very high (~800-1000nA) and doesn't go down already four days, but never tripped: most likely the HV caps have problems. Other than that all the channels on #3 are fine. Vlad applied today HV on cell #2 (wire frame #28), the current was initially 500nA but then started going up. It turned out Anatoly doesn't have a record that he had replaced the HV caps on #28. We will finished with the tests on cell #2 and cell #1 and then decide what exactly we want to disassemble.

Engineering update

- Bill gave us some detail about the cooling system: ~2gal, 32psi, tubes outside of the packages are (special) plastic 3/4" ID, brass compression fittings, manifolds are made out of Norel, tubes on the packages are copper 2.79mm ID. Water or Fluorinert: Fluorinert is $500/gal but volume is only 2 gal; the main concern is about leakages and special pump and fittings that are needed. Water leakage can cause damages, need to cover BCAL and try somehow to cover the manifolds. It turned out at the LHC experiments there's only one example when water is used for cooling a detector that is not accessible: the ECAL for CMS. In this case, however, many additional systems are included (see text above) to monitor the pressure, temperature and flow and in case of leakage to separate sections of the system and evacuate the water from there. All at the meeting, including Bill and Eugene, think Fluorinert is a better choice.

- Bill went through the drawings linked above, explaining the cooling system. There are two loops, inner and outer. The outer uses water. There's a heat-exchanger between the two loops. Beni and Eugene asked about its reliability, what is the pressure difference in the inner and outer loops. The cooling system cart is supposed to be placed on the floor downstream after the magnet, but Eugene suggested to keep this space empty for the future Cherenkov detector.

Electronics update

- Chris: no grounding clips yet. The sole source PR about the PCBs was returned to Chris: not enough reasons for the sole source. Chris will ask Fernando for help in formulating the sole source argumentation.

LV cable assignment

- Vlad: LV scheme is linked above, at the end of the file the cables are shown with the corresponding pre-amps and their labels for the cathodes: four pre-amps per cables. For the wires the cables are identified by the range of the channels on the PCB to which the LV cable is connected. We will put these lables on both sides of the LV cables.

Test set-up at 126

- Beni: the configuration of the DAQ to be used with two new Linux ROCs is close to complete. Old TIs will be used for the FDC DAQ system.

Other

- Beni: next Wednesday (7/11) at 10am there will be a meeting about the gas system.