Difference between revisions of "Minutes-2-13-2014"

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= Agenda =
 
= Agenda =
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# Installation [http://www.jlab.org/Hall-D/detector/fdc/installation/FDCinst02132014_1.JPG],[http://www.jlab.org/Hall-D/detector/fdc/installation/FDCinst02132014_2.JPG],[http://www.jlab.org/Hall-D/detector/fdc/installation/FDCinst02132014_3.JPG],[http://www.jlab.org/Hall-D/detector/fdc/installation/FDCinst02132014_4.JPG],[http://www.jlab.org/Hall-D/detector/fdc/installation/FDCinst02132014_5.JPG],[http://www.jlab.org/Hall-D/detector/fdc/installation/FDCinst02132014_6.JPG],[http://www.jlab.org/Hall-D/detector/fdc/installation/FDCinst02132014_7.JPG],[http://www.jlab.org/Hall-D/detector/fdc/installation/FDCinst02132014_8.JPG],[http://www.jlab.org/Hall-D/detector/fdc/installation/FDCinst02132014_9.JPG]
+
# Installation [http://www.jlab.org/Hall-D/detector/fdc/installation/FDCinst02132014_1.JPG],[http://www.jlab.org/Hall-D/detector/fdc/installation/FDCinst02132014_2.JPG],[http://www.jlab.org/Hall-D/detector/fdc/installation/FDCinst02132014_3.JPG],[http://www.jlab.org/Hall-D/detector/fdc/installation/FDCinst02132014_5.JPG],[http://www.jlab.org/Hall-D/detector/fdc/installation/FDCinst02132014_6.JPG],[http://www.jlab.org/Hall-D/detector/fdc/installation/FDCinst02132014_7.JPG],[http://www.jlab.org/Hall-D/detector/fdc/installation/FDCinst02132014_8.JPG],[http://www.jlab.org/Hall-D/detector/fdc/installation/FDCinst02132014_9.JPG]
 
# Engineering (Bill)
 
# Engineering (Bill)
 
# Electronics  [http://www.jlab.org/Hall-D/detector/fdc/installation/Tests_Feb_2014.xlsx problematic channels] (Chris, Nick)
 
# Electronics  [http://www.jlab.org/Hall-D/detector/fdc/installation/Tests_Feb_2014.xlsx problematic channels] (Chris, Nick)
 
# Mini-DAQ results [https://halldweb1.jlab.org/elog-halld/FDC FDC E-log] (Beni)
 
# Mini-DAQ results [https://halldweb1.jlab.org/elog-halld/FDC FDC E-log] (Beni)
 
# Other
 
# Other
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−
<!--
 
  
 
= Minutes =
 
= Minutes =
  
−
Participants: Fernando, Dave, Nick, Chris, Simon, Beni, Eugene, and Lubomir.
+
Participants: Eugene, Fernando, Bill, Dave, Nick, Chris, Simon, Beni, and Lubomir.
  
 
== Installation ==
 
== Installation ==
  
−
- Casey, Tina and Anatoly finished cabling the FDC at the detector side and it looks nice (first picture attached). On Tuesday the platform on the right side was opened and today Nick and Chris started routing the right bottom quadrant to the electronics. They are done with package #4 working now on #3.  
+
- On Thursday last week we inserted the FDC into the magnet (see pictures attached). It was taken out of the magnet on Monday. The tests were successful and we learned how to better handle the cables during insertion, what we discussed on the meeting. As Chris suggested, during the extraction, we used a strap to keep the cables up when moving the FDC. Bill suggested, for the final insertion, to use bearings (at least three) attached to the rails to be able to move the cables together with the rest, FDC and the mesh. Another discussion: how to attach the cables to the face of the magnet. On Monday we already exercised this at one quadrant using holding rings attached to the magnet. The main problem is that one has to spread the cables evenly around the periphery to make space for the CDC and also to be able to work on the BCAL modules. Beni proposed to extend the mesh further at the upstream side to cover completely the CDC, however the question was if there will be space to work around the BCAL modules. Bill proposed to build a ring (attached to the platform) with the same diameter as the mesh to hold the cables and, at the same time, be able to work on the other detectors. Fernando proposed to build a bigger movable ring attached to the face of the magnet, to support the cables.  
  
−
- HV: was stable since the beginning of the week at +2200V/-500V, except for 6 channels at +2200/-450V and three channels at +2200/-500V, out of 96 total number of HV channels. Such change of the field voltage on these 9 channels affects the biggest drift times/distances where the resolution is in any case poor, so the average track resolution will not be affected. Note also that +2200V is the upper limit of the HV range and we may not need to be there.
+
- Before the insertion, the cooling system failed again, the reasons are unknown so far, but there was no LV at this time. During the insertion the Fluorinert houses were disconnected and taped with duck tape at the chiller side (due to the lack of proper caps), as a result we lost >1 gal of Fluorinert: need proper caps for the final insertion!
  
−
- Gas: since Tuesday we are running gas at 400ccpm (according to the mass flow controller set point) compared to 800ccpm before, because we don't have more bottles and the next ones are expected to come next week. This morning somebody working at upstream face of the magnet, pulled the exhaust gas line and we found (also in the morning) the bubbler and a "quick-connect" connector disconnected. As a result the pressure went down to ~20Pa from ~60Pa. The pressure recovered in about two hours. At the end of last week one of the bubblers stopped bubbling and the pressure started increasing (as usual), however, after inserting a tube at the output of the bubbler going inside the oil (second picture attached) it started bubbling again with high rate and the bubbling is very stable since then.  
+
- Tom informed us that the power in the Hall and the CC will be OFF for 3-4 days starting February 20 (next Thursday). For the FDC we need the gas running all the time and will have to replace the mass flow controller (which requires power) with a rotameter. To avoid potential high pressure in the chamber with such a system Beni suggested installing a bubbler at the gas input.
  
−
- Dave proposed to put a plastic shield at the downstream side of the FDC to protect the gas and other FDC stuff there. Also expect that the test of the BCAL water cooling system which is next to the FDC, will start next week (need an umbrella!).
+
== Engineering == 
  
−
== Engineering ==
+
- Bill will travel to Hexagon Metrology in Charlotte, NC next Wednesday/Thursday to scan the cathode.
  
−
Bill was busy at another meeting, but he communicated with Lubomir:
+
- We need to modify the mesh to make sure there are no closed loops and also to insulate it from the FDC packages (now it's connected through two metal plates). The mesh will have a separate ground.
  
−
- We have now the report (attached) of the survey of the 16 reflectors done in December when the FDC was inside the magnet. In z-direction, the deviations from the nominal are not more than ~0.5 mm resulting of a pitch and yaw less than 0.4 mrad. Such deviations will have just a little contribution to the resolution even if not corrected for. It would be interesting to compare with the survey results when the FDC was outside of the magnet.
+
- Dave started working on the hardware shut off of the LV crate from the chiller. He needs to identify how exactly to interpret the signals about the chiller status and then will figure out with Fernando what the PCB should be doing. The board can be mounted on the same rack (back side) where the LV crate is. As for the MPOD controller settings Dave will talk to Hovanes.
−
 
+
−
- Bill received an answer from BROOKS: the mass flow controllers are to be blamed and now both the set and the read-out values are different from the actual flow. Beni: all the mass flow controllers that have been re-calibrated in the second batch, 7 in total, have the same problem. We have to send them for fixing a.s.a.p., still we want to keep one to be used in the temporary gas system that we have now for the FDC. The two mass flow controllers that have been re-calibrated first, are working fine (now in EEL126). 
+
−
 
+
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- Bill found a company (Hexagon Metrology) in Charlotte, NC that has the machine (MCC) to scan the cathode. Bill is arranging a trip to there with the cathode to do the measurement in the next few weeks.
+
  
 +
<!--
 +
 
== Electronics ==
 
== Electronics ==
  

Revision as of 17:57, 13 February 2014

February 13, 2014 FDC meeting

Agenda

  1. Installation [1],[2],[3],[4],[5],[6],[7],[8]
  2. Engineering (Bill)
  3. Electronics problematic channels (Chris, Nick)
  4. Mini-DAQ results FDC E-log (Beni)
  5. Other

Minutes

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

Installation

- On Thursday last week we inserted the FDC into the magnet (see pictures attached). It was taken out of the magnet on Monday. The tests were successful and we learned how to better handle the cables during insertion, what we discussed on the meeting. As Chris suggested, during the extraction, we used a strap to keep the cables up when moving the FDC. Bill suggested, for the final insertion, to use bearings (at least three) attached to the rails to be able to move the cables together with the rest, FDC and the mesh. Another discussion: how to attach the cables to the face of the magnet. On Monday we already exercised this at one quadrant using holding rings attached to the magnet. The main problem is that one has to spread the cables evenly around the periphery to make space for the CDC and also to be able to work on the BCAL modules. Beni proposed to extend the mesh further at the upstream side to cover completely the CDC, however the question was if there will be space to work around the BCAL modules. Bill proposed to build a ring (attached to the platform) with the same diameter as the mesh to hold the cables and, at the same time, be able to work on the other detectors. Fernando proposed to build a bigger movable ring attached to the face of the magnet, to support the cables.

- Before the insertion, the cooling system failed again, the reasons are unknown so far, but there was no LV at this time. During the insertion the Fluorinert houses were disconnected and taped with duck tape at the chiller side (due to the lack of proper caps), as a result we lost >1 gal of Fluorinert: need proper caps for the final insertion!

- Tom informed us that the power in the Hall and the CC will be OFF for 3-4 days starting February 20 (next Thursday). For the FDC we need the gas running all the time and will have to replace the mass flow controller (which requires power) with a rotameter. To avoid potential high pressure in the chamber with such a system Beni suggested installing a bubbler at the gas input.

Engineering

- Bill will travel to Hexagon Metrology in Charlotte, NC next Wednesday/Thursday to scan the cathode.

- We need to modify the mesh to make sure there are no closed loops and also to insulate it from the FDC packages (now it's connected through two metal plates). The mesh will have a separate ground.

- Dave started working on the hardware shut off of the LV crate from the chiller. He needs to identify how exactly to interpret the signals about the chiller status and then will figure out with Fernando what the PCB should be doing. The board can be mounted on the same rack (back side) where the LV crate is. As for the MPOD controller settings Dave will talk to Hovanes.


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