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How much force do we anticipate on making these connections?10lbs?
20lbs?<br>
<br>
Tim<br>
<br>
Gerard Visser wrote:
<blockquote type="cite" cite="mid4AB3D857.2090701@indiana.edu">
<pre wrap="">Hi Curtis,
I endorse completely your comments regarding deflection and
reliability! There should either be more mechanical support (which could
serve as a ground connection, or not) or else there should be attention
to make an insertion/extraction tool and features in the design to
insert/extract the HVB without applying too much force that strains the
wire connections.
For the wire pin to the ground sockets, for instance there is
<a href="http://www.mill-max.com/pdf/datasheet/pin_rec_catalog/8000-0-01-15-00-00-03-0.pdf">http://www.mill-max.com/pdf/datasheet/pin_rec_catalog/8000-0-01-15-00-00-03-0.pdf</a>
if you would be able to use a #19 or #20 wire. It is just slightly too
small for #18. But IMHO it should be enough - unless there is a
mechanical consideration about the wire diameter passing through the gas
seal that I don't know about.
Sincerely,
Gerard
Curtis A. Meyer wrote:
</pre>
<blockquote type="cite">
<pre wrap="">Hi Everyone -
a couple of points on the grounding connection.
Sometime ago, we had proposed "continuing" one of the legs that
supports
the connectors for the HV-boards through the gas plenum to the endplate.
This
standoff would then serve to both support the HV connector and provide a
solid
ground connection to the end plate. The one concern is that it might not
be possible
to place one support for each connector such that the feed through can
carry through
to the end plate.
Assuming that the above is not possible (which we still feel would
be the best grounding
and support scheme), then we are worried that there are not enough stand
offs in the current endplate, there are only eight as far as we can tell
in the current design.
We are very concerned that there are not enough standoffs to support
the swiss cheese
plate, particularly during insertion and removal of the high-voltage
cards. What we see with
the models that we have at CMU is that the force needed to insert and
pull the card is
sufficient to actually compress or pull-out the plastic plates. The way
the connection
scheme now goes. This distortion becomes a force either directly on the
crimp pin,
or on the glue joint that seals the chamber. These have the potential to
break wires
in the straws or break the gas seals every time a HV board is changed.
It is important
that additional standoffs be added, either during or after manufacture
of the Al endplate.
Finally, assuming that we adopt Fernando's connector, we need to
know if there is a
source of the .020 male part that can be soldered to the .040 wire and
is inserted in the
press-fit hole. The connector itself is quite slick and the 60gm force
needed to engage
it seems fine. But the male part is equally important to this working.
-- Curtis
</pre>
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