[Dsg-hallb_magnets] [New Logentry] Follow-up Re: Solenoid fast dump at 2416 A

[Brian Eng]

Yes, most of the "unknown" cause fast dumps look like that, the LCW PV has a spike for ~15 minutes total and ~10 minutes into it the Solenoid has fast dumped.

However, 16 and 17 the PV was bad for quite a long time before the magnet dumped, so that isn't always the case.

https://userweb.jlab.org/~beng/images/Solenoid%20Fast%20Dumps%20&%20LCW/

----- Original Message -----
> From: "Pablo Campero" <campero at jlab.org>
> To: "Amrit Yegneswaran" <yeg at jlab.org>
> Cc: jonesc at jlab.org, "dsg-hallb magnets" <dsg-hallb_magnets at jlab.org>
> Sent: Monday, November 5, 2018 11:57:50 AM
> Subject: Re: [Dsg-hallb_magnets] [New Logentry] Follow-up Re: Solenoid fast dump	at 2416 A

> Hello,
> 
> Correlation of the PV LCW92 signal with the MPS water flow and Dump contact
> signals are showed in the attached plot.
> As we can see, the spikes on LCW92 signal starts ~ 10 min before the MPS Dump
> Contact signal trips.
> Also noticed that the MPS bit BF used to monitor MPS internal status for water
> flow trips at the same time of the MPS dump contact within +/- 500 ms.
> 
> Regards,
> Pablo
> 
> 
> From: "Amrit Yegneswaran" <yeg at jlab.org>
> To: "Brian Eng" <beng at jlab.org>
> Cc: jonesc at jlab.org, "dsg-hallb magnets" <dsg-hallb_magnets at jlab.org>
> Sent: Monday, November 5, 2018 11:32:31 AM
> Subject: Re: [Dsg-hallb_magnets] [New Logentry] Follow-up Re: Solenoid fast dump
> at 2416 A
> 
> i concur brian.
> who is the person who tells us what this lcw92 PV measures?
> which brings up the question, tyler posed: how come the torus is unaffected?
> 
> i'm informed by amanda, pablo, peter, and tyler that there is a correlation
> between this PV and MPS water flow.
> could it be the water flow hiccups long enough to initiate the dump?
> but wouldn't this affect all the halls or is this 92 signal only for hallb?
> are the thresholds/flows for the solenoid and torus different?
> 
> 
> 
> 
> 
> 
> 
> From: "Brian Eng" <beng at jlab.org>
> To: sandoval at jlab.org
> Cc: jonesc at jlab.org, "dsg-hallb magnets" <dsg-hallb_magnets at jlab.org>
> Sent: Monday, November 5, 2018 10:53:49 AM
> Subject: Re: [Dsg-hallb_magnets] [New Logentry] Follow-up Re: Solenoid fast dump
> at 2416 A
> 
> Did we ever find out what this PV actually means?
> 
> After going through the 21 fast dumps that Pablo put in his summary table either
> we have an explanation for the dump (QDs, Cryo, etc) or for _all_ the unknown
> ones there's spikes on this PV, basically if it goes above 5 the Solenoid is
> going to dump. Scrolling through the archives I've only found a few cases where
> the magnet is on (at low current < 500 A) and there's spikes above 5 (but < 3
> min) where it didn't dump. All the other spikes in that PV the Solenoid was
> off.
> 
> I think finding out what exactly this PV is will help narrow down what in the
> MPS is causing the dump. Flow? Conductivity? Something else? Also why isn't the
> Torus MPS effected in the same way.
> 
> ----- Original Message -----
>> From: sandoval at jlab.org
>> To: jonesc at jlab.org, "dsg-hallb magnets" <dsg-hallb_magnets at jlab.org>
>> Sent: Friday, November 2, 2018 10:30:06 AM
>> Subject: [Dsg-hallb_magnets] [New Logentry] Follow-up Re: Solenoid fast dump at
>> 2416 A
> 
>> Follow-up Re: Solenoid fast dump at 2416 A
>> 
>> 
>> * Edit
>> * Delete
>> 
>> 
>> Lognumber 3619729 . Submitted by sandoval on Fri, 11/02/2018 - 10:27 . Logbooks:
>> HBLOG HBSOLENOID
>> References: 3619588 - Solenoid fast dump at 2416 A
>> 
>> 
>> Seems to be coorelation of Hall B solenoid fast dumps with lcw:92_Flow_Makeup
>> 
>> Not sure what this PV actually means for hall B