Main INDEX
Monthly INDEX
PREV
NEXT
Make New Entry,
Make Followup Entry
User name dalton
Log entry time 18:34:22 on August 21, 2009
Entry number 285160
Followups:
keyword=Day summmary
After the hall was locked up at noon, a controlled access was made to
work on the trigger.
At about 15:00, the hall went to power permit to test the 9th dipole
mapper. The mapper could be energised and moved through the magnet but
consistently read zero both through the remote communication and on the
face. A multiplexer was swapped out with one from Hall C as a test.
This did not fix the problem and was backed out.
At about 16:30, the hall was dropped into controlled access to reset LHRS
quad 3 and RHRS quad 2 and 3. The first PSS interlock door at the hall
entrance was worked on at this time too.
The hall was again put into power permit and further work on the 9th
dipole mapper was performed. The NMR electronics unit was swapped out
with one from Hall C as a test. The new unit appears to work well in the
shed, getting a lock on frequency and having a more promising scope
trace, but the values in the software are still zeros. The next
suggestion is to try replacing the MVME 712/M card. At this point the
accelerator issues have taken precedence and work has stopped. The Hall
C unit remains with us for the moment.
A copy of this log entry has been emailed to: brads@jlab.org