[Dsg-hallc_nps] [EXTERNAL] Re: Re: NPS HV cabling/connector questions

Carlos Munoz Camacho munoz at jlab.org
Tue Aug 18 12:02:55 EDT 2020


Dear Brad,

   thanks for the reminder. I talked to Thi yesterday about the large HV
SAMTEC connectors at the top of the NPS box. Indeed, they are only rated
for 850V, but he has tested each of them individually up to 1500 V and
found no issues with none of them. The same should apply to the (small)
SAMTEC connectors on the PMT voltage dividers, although that was Fernando's
group choice. We are happy to discuss this further if you think this may be
an issue, or additional tests are recommended.

Concerning the layout inside the box, Emmanuel provided a few detailed CAD
drawings that I put here:

www.jlab.org/~munoz/NPS_cables

I annotated some of the elements in the .pdf/.pptx file attached. Let me
know if that helps, or you want more details (or additional views).

Thanks for your help with this.

Best,
Carlos


On Tue, Aug 18, 2020 at 5:10 PM Brad Sawatzky <brads at jlab.org> wrote:

> Hi Carlos,
>
> Just a friendly ping on the SAMTEC issue/questions.
>
> All the best,
> -- Brad
>
> On Thu, 30 Jul 2020, Brad Sawatzky wrote:
>
> > Ah, now I understand why the SAMTEC part numbers were for a double ended
> > assembly.  They were copy-pasted from the internal grey HV connections
> > between the large PCB and the inside patch panel connection. (ie. slide
> > 12 on the PDF you link to below).
> >
> > OK, it'll be good to hear Thi's comments on the HV specs for those
> > larger SAMTEC connectors.  Thanks.
> >
> > More details models/specs on the internal cabling would be appreciated,
> > but things are already making more sense to me now.
> >
> > -- Brad
> >
> > On Thu, 30 Jul 2020, Carlos Munoz Camacho wrote:
> >
> > > Dear Brad,
> > >    thanks for the detailed documentation of the several points. I had
> > > misunderstood which SAMTEC connectors you were referring to (I thought
> you
> > > were referring to the ones attached to the PMTs, and not the ones at
> the top
> > > of the box).
> > > I will check the safety specs of this with the engineer who designed
> the
> > > cables and the boards (Thi). Unfortunately he's away on vacations
> until Aug
> > > 17, but I'll get back to you then. All cables and panels are
> fabricated now.
> > > But if we find a safety issue, we will of course reconsider things.
> > > Concerning the CAD drawing, I can send that to you next week when
> Emmanuel
> > > will be back at the lab. In the meantime, you could see in page 11
> (left)
> > > of [1]https://wiki.jlab.org/cuawiki/images/7/7e/ERR_Calorimeter.pdf a
> layout
> > > of the boards. The HV is distributed through the flat cables at the
> top of
> > > the board (and connected to the top of the box). The HV then goes out
> > > through FISCHER connectors on the right side of the PCB board and fed
> to the
> > > PMT voltage divider through another (smaller) SAMTEC connector (the
> one I
> > > thought you were referring to). Let me know if you would need more
> details
> > > (other than a better quality/zoom version of that). I should be able to
> > > provide the routing of the PCB board if you need.
> > > Thanks,
> > > Carlos
> > > On Thu, Jul 30, 2020 at 8:44 PM Brad Sawatzky <[2]brads at jlab.org>
> wrote:
> > >
> > >   Hi Carlos,
> > >
> > >   Just a few questions to follow up on the SAMTEC connector and long HV
> > >   cable issues.
> > >
> > >   Just so we're working off the same page, the information I'm going
> off
> > >   of is noted in these attachments:
> > >     1. NPS_Cables_Transparents.pdf
> > >        - See p.6 -- p.8 for the SAMTEC part numbers, and the pin map
> from
> > >          the Radiall connector <--> SAMTEC connector group.
> > >
> > >     2. SAMTEC-*.pdf
> > >        - SAMTEC catalog pages for the PMSD cable assemblies, and the
> > >          discrete IPBD connectors, etc.
> > >
> > >     3. NPS_frame_connector_layout.pdf
> > >        - A simple CAD render of the patch-panel(s) on the exterior of
> the
> > >          NPS chassis.
> > >
> > >     4. NPS-cabling-inside-chassis_25Jun2019.pdf
> > >        - CAD render of the interior of the NPS detector chassis
> > >
> > >   The 'PMSD-XX-206-K-D-LUS' called out in [1] are technically complete
> > >   cable assemblies (double-ended, including wire).  AFAICT, the
> relevant
> > >   discrete connectors are the IPBD units.
> > >
> > >   Either way, the PMSD and IPBD connectors are only rated to 600 VDC,
> but
> > >   the production HV is around 1100V.  There is a comment on the SAMTEC
> > >   assembly document that they hi-pot the cable assembly to 1000V as
> part
> > >   of the QA, so it is *possible* that these parts could be OK, but
> it'll
> > >   certainly require some kind of safety review, at minimum.  (See
> > >   documents in [2].)
> > >
> > >   Has procurement and fabrication of the HV patch panel on the NPS
> roof in
> > >   [3] already begun?  Are we locked into that design, or is there
> still a
> > >   window to redesign that patch panel around different connectors, if
> > >   needed?
> > >
> > >   Can you send a more detailed assembly/design model that shows how the
> > >   internal HV connections inside the NPS box are are laid out?  That
> is,
> > >   some shop drawings or zoomed CAD images that show connections from
> the
> > >   PMTs to the green panel area in [4], and from the green panel area to
> > >   the interior HV patch panel on the roof (ie. grey cables in [4]).
> > >
> > >   -- Brad
> > >
> > >   --
> > >   Brad Sawatzky, PhD <[3]brads at jlab.org>  -<>-  Jefferson Lab / Hall
> C /
> > >   C111
> > >   Ph: 757-269-5947  -<>-  Fax: 757-269-5235  -<>- Pager:
> > >   [4]brads-page at jlab.org
> > >   The most exciting phrase to hear in science, the one that heralds new
> > >     discoveries, is not "Eureka!" but "That's funny..."   -- Isaac
> Asimov
> > >
> > > References
> > >
> > >    Visible links
> > >    1. https://wiki.jlab.org/cuawiki/images/7/7e/ERR_Calorimeter.pdf
> > >    2. mailto:brads at jlab.org
> > >    3. mailto:brads at jlab.org
> > >    4. mailto:brads-page at jlab.org
> >
> --
> Brad Sawatzky, PhD <brads at jlab.org>  -<>-  Jefferson Lab / Hall C / C111
> Ph: 757-269-5947  -<>-  Fax: 757-269-5235  -<>- Pager: brads-page at jlab.org
> The most exciting phrase to hear in science, the one that heralds new
>   discoveries, is not "Eureka!" but "That's funny..."   -- Isaac Asimov
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <https://mailman.jlab.org/pipermail/dsg-hallc_nps/attachments/20200818/39673df4/attachment-0001.html>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: NPS cables.pdf
Type: application/pdf
Size: 1139614 bytes
Desc: not available
URL: <https://mailman.jlab.org/pipermail/dsg-hallc_nps/attachments/20200818/39673df4/attachment-0001.pdf>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: NPS cables.pptx
Type: application/vnd.openxmlformats-officedocument.presentationml.presentation
Size: 2571955 bytes
Desc: not available
URL: <https://mailman.jlab.org/pipermail/dsg-hallc_nps/attachments/20200818/39673df4/attachment-0001.pptx>


More information about the Dsg-hallc_nps mailing list