sPHENIX discussion of the superconducting solenoid

["Lambiase, Robert" <lambiase AT bnl.gov>]

Hi Kin,

This is a very comprehensive test procedure.  I’d like to add a few details for the quench detection based on a first pass look of the documentation I saw this weekend.

• Coil balance – The two halves are not equal.  The inner coil has a smaller aperture and 531 turns, while the outer coil has a larger aperture and 536 turns.  The scaling factor to equalize the ramp voltage of the two halves should be determined.  SLAC spent a bit of time doing this.  We should determine this number.
• Quench – The dump switch was triggered if there was an instantaneous exceeding delta V of IST (50mV) or an integral (I haven’t seen the time constant yet) of the delta V by INTEG (I need to find out this number) exceeding 8V.  The integrator was set to zero any time the delta V went below INTEG.  Perhaps we should monitor this integral as well as the instantaneous trip vlaue.  As far as I could tell, they didn’t use Ldi/dt in any calculations.

Bob

From: Kin Yip <kinyip AT bnl.gov>
Date: Monday, April 13, 2015 at 3:36 PM
To: "sphenix-magnet-l AT lists.bnl.gov" <sphenix-magnet-l AT lists.bnl.gov>
Cc: "McKeon, William F" <wmckeon AT bnl.gov>
Subject: [Sphenix-magnet-l] A draft plan for the sPHENIX Magnet Low Current Test in Bldg. 912

Hi,

Joe Muratore has just sent me a draft plan for the low current test.  ( Thanks Joe !! )

For convenience, I've just put his plan (in Word document) to the agenda page :
 
https://indico.bnl.gov/conferenceDisplay.py?confId=1105

Please read and you may comment to the mailing list; or otherwise we'll discuss this on Apr. 22, 2015.

Kin