OWG Meeting 8-Dec-2009

Agenda

• Announcements -
  • EPICS course at US Particle Accelerator School in Boston, MA Jun 14-18 2010
• Review of minutes from 11-Nov-2009 meeting
• TI and TD boards - William Gu
• Do we need a redundant PLC system? - Elliott
• Coil test update - Elliott
• Other electronics and trigger status reports - Fernando, Chris, Ben, Ed, Alex, Dave

Time/Location

Note change of date

1:30 PM Tues 25-Nov-2009 CC F326

Next Meeting

1:30 PM Wed 6-Jan-2009

Minutes

Attendees: Elliott W, Simon T, Fernando b, Carl T, Vardan G, Ben R, William G, Chris C, Ed J, Hai D, Dave D, Mark I, Beni Z.

Trigger Interface (TI) and Trigger Distribution (TD) Combined Function Board

William presented his concept for a combined TI/TD board, an alternative to our original plan to have separate TI and TD boards.

• H-D needs about 70 TI boards and 16 TD boards.
• Easy to fit all functionality on one board.
• Populate differently for different applications.
• Can act as a Trigger Supervisor (TS) for small systems.
• Front-panel space at a premium.
• Fiber transceivers are the driving cost at $500 each.
• Can have 1 to 8 fiber transceivers.
• Not all possible TI and TD configurations will work if you want TS functionality as well or want 8 transceivers.

In general, the engineers think this is the way to go whereas the physicists are dubious about introducing additional complexity compared to two simpler board designs. An important question is how much does the TI version cost compared to a dedicated TI board, since we need many more TI's than TD's.

Redundant PLC's

Elliott discussed the recent Hall C PLC failure and implications for H-D.

• Hall C PLC failed after 5 years flawless performance.
• Auto-failover to redundant (backup) PLC worked fine, no interruption to the control system.
• Cause was single-bit error in PLC memory.
• Our version has single-correct/double-detect, so this error would not cause our PLC to fail.
• Cost of redundancy for H-D less than $10k, so it seems to be cheap insurance.
• Don't have to decide until very late, around 2013.

Coil Test Status

• Steady progress, bottoms-up FastTrack schedule near complete.
• Many delays due to vendors and to slow progress on coil 1 repair.
• Coil 1 in the process of being closed up prior to leak-testing.
• Current schedule has tests completing in May 2012. Top-down estimates gave late 2011. Difference due to very long delivery of cryo can, delay in coil 1 repair, and more conservative 12 week estimate for one coil turnaround cycle instead of 6-8 weeks.