Difference between revisions of "Minutes-3-21-2013"
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- Dave: the last two wire frames populated. 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). | - Dave: the last two wire frames populated. 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 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 | + | - 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 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 == | == Installation == | ||
− | - | + | - The last, "frozen" schedule changed 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 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?? |
== Engineering == | == Engineering == |
Revision as of 16:31, 21 March 2013
March 21, 2013 FDC meeting
Agenda
- Production Construction Tracking (Dave)
- Package #3 repair
- Installation schedule(Lubomir)
- Engineering (Bill)
- Cooling manifold installation and tests
- Electronics (Chris, Nick)
- Tests at EEL126 FDC E-log (Beni)
- Other