[dsg-svt] Location of SVT sensitive components on the service cart

[Chris Cuevas]

Hi Brian,

Nice SEE report but I did not read any mention of failures noted for the 
network switch gear during KPP or during other periods. I also am 
concerned about the small Ethernet magnetics in the switches that are 
probably more susceptible to magnetic fields. Ive seen the fringe field 
models for the Soleniod, so maybe moving them radially away from the 
beam pipe will be adequate. Moving the network switches to the deck 1 
space frame racks is easy enough, and you are right about buy/provide 
the network cable to run from the cart to the space frame rack.  A 
bundle of 16-20 RJ45 cables is not too bad.  We should also invest in a 
network controlled AC power strip in the space frame rack that would 
allow remote reset for these network switches from the counting house or 
other remote control.  Ill check with Sergey because there may already 
be one in the space frame rack that holds the network gear.

The UPS relocation is a more challenging job, and I still wonder why 
these are needed.  We are on the topic of radiation 
sensitivity/susceptibility and I know these UPS are always run in 
inverting mode, so the switching devices internal are most likely power 
FET, which are known to be susceptible to radiation damage. Something to 
think about.

Relocating the UPS to the space frame racks will require a new array of 
conduits be installed to power devices on the SVT cart because you 
cannot run AC power cords in cable tray.  The new clean power 
installation for the cart should be more than adequate and the smart 
distribution strip can be monitored. I do not recall if the output ports 
can be switched, but if yes, it would be another way to reset devices on 
the cart that do not have remote reset capability.

Keep me posted,

-Chris

~~~~~~~~~~~~~


On 3/3/2017 1:49 PM, Brian Eng wrote:
> Hall B will need to buy/provide the network cable and connectors to run 16 cables instead of the 2 that were already run if the switches need to be moved off the cart.
>
> There would also need to be some coordination with fast electronics for the UPSes to be moved since none of the AC power cables would reach.
>
> Personally I'd prefer to move (radially away from the beam) the equipment and/or shield it before moving it off the cart.
>
>> On Mar 3, 2017, at 1:23 PM, Yuri Gotra <gotra at jlab.org> wrote:
>>
>> https://userweb.jlab.org/~gotra/svt/mtg/tcb/2017_03_03_err_tcb.pdf
>>
>>
>> On 3/3/17 11:12 AM, Brian Eng wrote:
>>> Hi Yuri,
>>>
>>> We can move the switches (and maybe some of the UPSes [this might require cart modifications by Hall B Engineering]) to the bottom corners of the cart, but moving them to the racks would be quite a big change (and a lot more time/money to implement).
>>>
>>> Is there any actual reason to think the corner locations on the cart are to high of a dose for the equipment to be placed?
>>> --
>>> Brian Eng
>>> Detector Support Group
>>> 757-269-6018
>>>
>>>> On Mar 3, 2017, at 10:32 AM, Yuri Gotra <gotra at jlab.org> wrote:
>>>>
>>>> Please review the current location of the SVT system components which are sensitive to radiation and consider moving what is possible from the service cart to the SVT rack further away from the beam. Moving the network switches would be desirable. Maybe the UPS too. Lowering the accumulated dose would increase reliability of the component and reduce the probability of the detector down time. Thank you
>>>>
>> <gotra.vcf>