Minutes from target meeting held May 27 2011 in 892-2-009

These minutes are available also from:

http://wwwcompass.cern.ch/compass/detector/target/Minutes/2011/

a) Magnet filled to 90 % level on Saturday evening. Add oil to the helium-4
pumps on Monday morning and start the helium-4 evaporator. Condense
helium-4 into the mixing chamber for empty target cell TE-calibration.

b) Problem in starting Danfysik power supply 854S for the solenoid. 
Communication failure between the control panel and the main board. 
Danfysik contacted on Wednesday morning and new main board ordered 
the same day. Fabrice: check internal voltages of the the power supply. 
Drawings are not up to date. No reaction from the main board to different
interlocks. Check plugged in accessory cards. The main board probably 
dead.

c) Start to remove helium from the magnet on Thursday morning. Pump out 
helium from the mixing chamber.

d) Thursday afternoon test impurities coming from helium-4 pumps. The pumps 
were stopped for half an hour. The helium liquefier purifier is regenerated 
every hour due to unknown impurities when the pumps are running. 

e) Fabrice: intervention on the brute water cooling water circuit on
Thursday afternoon. The pressure difference between the input and output
varies between 0.5 and 1.5 bar. The water filter looks ok.

f) Fabrice: new diffusion pump from Edwards Vacuum for the isolation vacuum 
arrived.

g) Yuri: test new remotely controlled microwave attenuator on Thursday with
Hiroki. 5 W input power used. For the Drell-Yan the attenuator could be
located at the entrance of the wave guides into the dilution cryostat.
Thus the present power control system on the microwave table is not used
any more. With new power supply more than 7 W microwave power is available.
The wave guides to the target platform are expected to have 4 - 6 times loss.

h) ELMB was installed into the pump room for monitoring pt100 thermometers.

i) Norihiro: upgrade the Siemens S7 300 PLC with new input modules.
Four new PT100s were cabled on the helium-3 roots motors. Only one motor
now does not have a temperature probe.

j) PST 2011 will take place at St. Petersburg Russia September 12-18 2011
http://pstp2011.lkst.ru/