1 / 6

Honeycomb grounding of the GLAST trays

Gamma-ray Large Area Space Telescope. Honeycomb grounding of the GLAST trays. Alessandro Brez INFN Pisa. Tray electrical conductivity:

elmo
Download Presentation

Honeycomb grounding of the GLAST trays

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Gamma-ray Large Area Space Telescope Honeycomb grounding of the GLAST trays Alessandro Brez INFN Pisa Tray electrical conductivity: Carbon Carbon, carbon fiber and Al core have good electrical conductivity, but are connected together with non conductive glue. The result is a poor electrical connection, 10-100W from element to element. EM tests demonstrated the need to have a good grounding of the tray parts

  2. MCM mounting system To avoid Carbon Carbon chipping, the MCM will be not mounted by means of M1.6 screws. There will be holes in the closeout and glued pins will replace the screws. The MCM will be glued (Scotchweld 2216 A/B gray). A tool will be used to take in place the MCM during glue curing time.

  3. MCM ground hole Pin GND hole Nusil 2646 closeout MCM – closeout connection The MCM ground will be electrically connected to the closeout using pins with conductive glue in the 3 ground holes.

  4. CORE CONNECTION: SOLUTION 1 MCM closeout Structural closeout Connection wire After the tray is completed, 4 grooves are machined across the MCM-structural closeout walls. The grooves are filled with a short conductive wire and with conductive glue (Nusil CV2646) The honeycomb is connected to the structural wall trough the venting hole by means of a glued wire. The MCM closeout wall is connected to the MCM ground with a pin glued with conductive adhesive Groove filled with conductive glue Venting hole Glue joint Experimental result: all the tray parts (closeouts, face sheet, honeycomb) are connected with low resistance <1W

  5. Core connection: Solution 2 1) Add to the honeycomb conductive cylinders ( gold plated kapton tubes ) glued with conductive adhesive 2) Put conductive glue on the closeout walls when the tray is assembled, in correspondence to the conductive cylinders. Push in place the closeout walls that will compress the cylinders

  6. Conclusions • The Minitower experience demonstrated the need of a good grounding of the honeycomb • A solution “1” has been successfully tested electrically connecting all the tray parts after the tray building. • A solution “2” with an internal connection of the parts, will be tested on the top/bottom trays of the EM tower. This solution seems more clean and easy. If in some cases this solution fails (R>1W between closeout and honeycomb), we can recuperate the tray using solution “1”. • Note: we are testing the connection Al foils / Al foil / Carbon Carbon with conductive gluing joints. After 1 month from gluing, R≾0.1W

More Related