[Sbs_gems] [EXTERNAL] Problems with J0 Mid

[Evaristo Cisbani]

Dear Anu,

also for the bottom J0 one should try to ramp the HV at 500 V and 1000 V to see
if the HV current exceed the maximum allowed current (13.5 and 26 uA).

Thanks
Evaristo

On Fri, 3 Dec 2021 03:32:29 -0500 Anuruddha Rathnayake
<adr4zs at virginia.edu> wrote:

> Hi All,
> 
> This is the 50 K replay of the run 12496. This run has been started when
> the issue is present but when it was still unknown. So the HV has been on
> for the J0 middle module. https://logbooks.jlab.org/entry/3955367
> 
> I would also like to bring everybody's attention about the INFN J0 bottom
> module's current instability issue that started to develop around 2 AM
> today. https://logbooks.jlab.org/entry/3955398
> I have instructed the shift crew to turn the module off until an INFN GEM
> expert contacts them.
> 
> Best,
> Anu
> 
> 
> On Thu, Dec 2, 2021 at 10:12 PM Ezekiel Wertz <ewertz at email.wm.edu> wrote:
> 
> > Hi Kondo,
> >
> > Thanks for the quick feedback. We will have to discuss the path forward,
> > but it is good to know that the problem is identifiable.
> >
> > Zeke
> >
> > On Thu, Dec 2, 2021 at 10:10 PM Gnanvo, Kondo (kg6cq) <kg6cq at virginia.edu>
> > wrote:
> >
> >> Hi Zeke,
> >> This crosses all the boxes of a shorted sector
> >>
> >> A gas window collapsed would not change the current.
> >>
> >> Best regards
> >> Kondo
> >> ------------------------------
> >> *From:* Sbs_gems <sbs_gems-bounces at jlab.org> on behalf of Ezekiel Wertz <
> >> ewertz at email.wm.edu>
> >> *Sent:* Thursday, December 2, 2021 9:52 PM
> >> *To:* Sbs_gems at jlab.org <sbs_gems at jlab.org>
> >> *Subject:* [Sbs_gems] [EXTERNAL] Problems with J0 Mid
> >>
> >> Hi Folks,
> >>
> >> I was alerted by the shift crew to a problem with J0 Middle. At the
> >> moment we are not entirely sure what has occurred, but the HV demonstrated
> >> some problems and the efficiency of the module has become greatly reduced.
> >> See the following log entries.
> >>
> >> https://logbooks.jlab.org/entry/3955216
> >> https://logbooks.jlab.org/entry/3955221
> >> https://logbooks.jlab.org/entry/3955220
> >>
> >> Also see the 50k replay plot for J0 mid on page 24
> >>
> >> https://logbooks.jlab.org/files/2021/12/3955238/summaryPlots_12496_bb_gem_for_shiftcrew.pdf
> >>
> >> Currently we suspect either a foil collapse or new shorted sectors in
> >> this module. But we are uncertain of the actual cause which is why I am
> >> contacting all of you. I have instructed shift crew to turn off J0 middle
> >> HV until further notice
> >>
> >>
> >> Ezekiel
> >>
> > _______________________________________________
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> >