sPHENIX discussion of the superconducting solenoid

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

Hi,

 

Ok.  We don’t need to wait until the next Maintenance Day to solve this puzzle.   Somehow, Ron Walker (CAS) was brave enough to power cycle the DMM of the DCCT

to show values.   ( If he asked me, I’d have discouraged him to. )

 

And as I show in the attached plot, the Mag_Current now (after Ron’s power cycling the DMM) went back to ~4596 A.   The plots at the top are voltage taps of NEG_GC_LEAD and

POS_GC_LEAD.  As Cryo is relying on the Mag_Current to set lead flow, increasing the current by ~93 A, the lead flow increases leading to decreasing resistances/voltages

of the voltage taps.

 

The DCCT and the Mag_Current provide separate readings of the same current … but obviously, they’re not totally independent and are also not the same (as Mag_Current didn’t go to 0

when DMM of the DCCT was shut).   The “circuit” is still a mystery to me 😅

 

 

Marianna: please don’t bother scheduling the CAS/Pablo’s works for the Maintenance Day on June 20 😊

 

Kin

 

From: Walker, Ronald <rwalker AT bnl.gov>
Sent: Tuesday, June 4, 2024 9:23 PM
To: Rosas, Pablo J <rosas AT bnl.gov>
Cc: Walker, Ronald <rwalker AT bnl.gov>; Yip, Kin <kinyip AT bnl.gov>
Subject: RE: DCCT shows nothing ?

 

Pablo, Kin,

 

The DMM required a power cycle,

It is functioning now.

 

Best,

 

Ron

 

 

 

 

 

 

Ronald Walker
Technical Specialist Electrical
C-A Support,
Collider Accelerator Department
Office: 631.344.2022 | Mobile: 631.742.6322
rwalker AT bnl.gov

𝕏 | Facebook | Instagram | LinkedIn

 

From: Rosas, Pablo J <rosas AT bnl.gov>
Sent: Tuesday, June 4, 2024 9:28 AM
To: Yip, Kin <kinyip AT bnl.gov>; Than, Yatming (Roberto) <ythan AT bnl.gov>; Van Kuik, Brian <vankuik AT bnl.gov>
Cc: Schultheiss, Carl <carls AT bnl.gov>; Pekrul, Winston <wpekrul AT bnl.gov>; Stewart, Jeffrey (AD) <jeffstewart AT bnl.gov>; Karl, Robert F <rkarl AT bnl.gov>; Costanzo, Timothy <tcostanzo AT bnl.gov>; Bezpalko, Yurii <ybezpalko AT bnl.gov>; Walker, Ronald <rwalker AT bnl.gov>
Subject: RE: DCCT shows nothing ?

 

Hello kin;

 

 

We may have lost the meter.

 

 

Thanks

 

 

Pablo

 

From: Yip, Kin <kinyip AT bnl.gov>
Sent: Tuesday, June 04, 2024 8:52 AM
To: Than, Yatming (Roberto) <ythan AT bnl.gov>; Van Kuik, Brian <vankuik AT bnl.gov>
Cc: Schultheiss, Carl <carls AT bnl.gov>; Rosas, Pablo J <rosas AT bnl.gov>; Pekrul, Winston <wpekrul AT bnl.gov>; Stewart, Jeffrey (AD) <jeffstewart AT bnl.gov>
Subject: DCCT shows nothing ?

 

Hi, Pablo,

 

I just went to 1008 mezzanine.

 

DCCT is not showing any reading ! dark ?

 

Kin

 

 

 

-------- Original message --------

From: "Than, Yatming (Roberto)" <ythan AT bnl.gov>

Date: 6/4/24 08:24 (GMT-05:00)

To: "Yip, Kin" <kinyip AT bnl.gov>, "Van Kuik, Brian" <vankuik AT bnl.gov>

Cc: "Schultheiss, Carl" <carls AT bnl.gov>, "Rosas, Pablo J" <rosas AT bnl.gov>, "Pekrul, Winston" <wpekrul AT bnl.gov>, "Stewart, Jeffrey (AD)" <jeffstewart AT bnl.gov>

Subject: Re: Did you guys adjust gas-cooled leak or the heating ?

 

Can you check cooling water supply temperature trend for the watercooled bus?

---

From: Yip, Kin <kinyip AT bnl.gov>
Sent: Tuesday, June 4, 2024 8:09 AM
To: Than, Yatming (Roberto) <ythan AT bnl.gov>; Van Kuik, Brian <vankuik AT bnl.gov>
Cc: Schultheiss, Carl <carls AT bnl.gov>; Rosas, Pablo J <rosas AT bnl.gov>; Pekrul, Winston <wpekrul AT bnl.gov>; Stewart, Jeffrey (AD) <jeffstewart AT bnl.gov>
Subject: RE: Did you guys adjust gas-cooled leak or the heating ?

 

Hello,

 

sPHENIX IR measurements don’t show any change in temperature around that time.

I just attach a plot.  ( In spite of the Chinese characters, it’s indicating June 3 (yesterday)

in the afternoon 😊)

 

[ Near that time, there was a warning for RHIC ring corrector lead flow :

http://www.cadops2.bnl.gov/elogs/entryList.jsp?DATABY=day&ELOG=Cryo&DATE=06/03/2024&DIR=none#1841695  ]

 

 

Kin

 

From: Than, Yatming (Roberto) <ythan AT bnl.gov>
Sent: Tuesday, June 4, 2024 7:58 AM
To: Yip, Kin <kinyip AT bnl.gov>; Van Kuik, Brian <vankuik AT bnl.gov>
Cc: Schultheiss, Carl <carls AT bnl.gov>; Rosas, Pablo J <rosas AT bnl.gov>; Pekrul, Winston <wpekrul AT bnl.gov>; Stewart, Jeffrey (AD) <jeffstewart AT bnl.gov>
Subject: Re: Did you guys adjust gas-cooled leak or the heating ?

 

Brian,

Can you get a trend for the lead flows?

Our supervisory server does is not trending the lead flows.

 

The leads exit temperatures, maintained by the heaters, did shift upward by 1.5K to 2K, so something changed.

Either the flow reduced or dynamic load went up, or the heater output went up.

 

If we cannot figure it out, we can try increasing the flow a bit to see if it changes things.

Is there an ambient air temperature sensor in the detector Hall? you can trend?

Is there a DI water temperature sensor you can trend?

 

Roberto

 

 

---

From: Yip, Kin <kinyip AT bnl.gov>
Sent: Tuesday, June 4, 2024 7:44 AM
To: Than, Yatming (Roberto) <ythan AT bnl.gov>; Van Kuik, Brian <vankuik AT bnl.gov>
Cc: Schultheiss, Carl <carls AT bnl.gov>; Rosas, Pablo J <rosas AT bnl.gov>; Pekrul, Winston <wpekrul AT bnl.gov>
Subject: RE: Did you guys adjust gas-cooled leak or the heating ?

 

Hi,

 

Yes, please let us know what you can find ☹

 

Kin

 

From: Than, Yatming (Roberto) <ythan AT bnl.gov>
Sent: Tuesday, June 4, 2024 7:38 AM
To: Yip, Kin <kinyip AT bnl.gov>; Van Kuik, Brian <vankuik AT bnl.gov>
Cc: Schultheiss, Carl <carls AT bnl.gov>; Rosas, Pablo J <rosas AT bnl.gov>; Pekrul, Winston <wpekrul AT bnl.gov>
Subject: Re: Did you guys adjust gas-cooled leak or the heating ?

 

No one adjust flowrate.

I will check.

 

---

From: Yip, Kin <kinyip AT bnl.gov>
Sent: Tuesday, June 4, 2024 7:22 AM
To: Than, Yatming (Roberto) <ythan AT bnl.gov>; Van Kuik, Brian <vankuik AT bnl.gov>
Cc: Schultheiss, Carl <carls AT bnl.gov>; Rosas, Pablo J <rosas AT bnl.gov>; Pekrul, Winston <wpekrul AT bnl.gov>
Subject: Did you guys adjust gas-cooled leak or the heating ?

 

Hello, Roberto and Brian,

Did you guys adjust the gas-cooling for the Current Leads of the sPHENIX Magnet yesterday (around 15:47) ?

On the plot, I saw a sudden rise in the negative/positive gas-lead voltage taps which correspond to a sudden drop in the magnet current ?!

Kin

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