sPHENIX discussion of the superconducting solenoid

["Yip, Kin" <kinyip AT bnl.gov>]

Hi,

 

A lot of data (Booster or other accelerators) are logged inside C-AD.  You can

try to correlate them and so far we haven’t found anything.  ( Angelika Drees

helped to find any beam loss or even in her pin-diode near the collimator etc. )

 

Lightning or power dip etc. would depend on the “timestamp”.   There was no known power dip around the time we tripped.

 

Kin

 

From: David Morrison <morrison AT bnl.gov>
Sent: Wednesday, June 7, 2023 12:06 PM
To: Yip, Kin <kinyip AT bnl.gov>; sphenix-magnet-l AT lists.bnl.gov
Cc: stefan.bathe AT baruch.cuny.edu
Subject: Re: What Carl, Chung and I have done today --- removal of "PLL loss"

 

Hi Kin,

If, as Ed hypothesized, the QLI trips have something to do with electrical noise (Booster, chillers, lightning, power dips, etc), do we have instrumentation available that would provide data about that?

Cheers,
Dave

On 6/7/23 12:01 PM, Yip, Kin wrote:

Hello,

 

So, the first two events that brought down the Magnet came with a strange thing: the quench detector didn’t tell us what voltage tap

caused it but just said “Program Stopped” and left us no “file” in the PIXe system ☹  ( The last one yesterday did tell us which

voltage tap caused the trip and left us a file. )

 

Today, we have asked Chung Ho to essentially remove the “PLL Loss” check which we have long suspected doing bad things to the

quench program (Labview) as it stopped the program at times that we don’t understand.   Carl has long wanted to remove

this “PLL Loss” check which he thinks is unnecessary as he used the same PLL board in RHIC and they don’t have a problem there.

( This “PLL Loss” check was insisted by the previous author who has left BNL; but Carl thinks that the way it checks was error-prone. )

 

It’s possible we might have 2/3 of the problems 😊

 

Kin

--

David Morrison  Brookhaven National Laboratory  phone: 631-344-5840

                Physics Department, Bldg 510 C    fax: 631-344-3253

                          Upton, NY 11973-5000  email: dave AT bnl.gov