Gentlemen
Some improvements were made to the Quads this morning to try to reduce the
frequency of nuisance trips.
1) The DC leads were inspected and the buss leads on Q2 and Q3 were retightened.
three of the four leads needed to be tightened.Q1 had been done the week before.
This is frequently the cause of these trips.
2)We also checked the operation of the quench detectors.
Specifically Q2 which had the most frequent trips was examined in detail.
The thresholds are all 10 mV and the balance looks excellent.
3) All magnets were operated together in the manner that seemed to be causing the
trips and none were observed.
4) The Shield house air conditioning was dead over the weekend.
This caused the switch box to fail.Assoon as the shield house door was opened and
the house cooled off it began working again.probably the PC hangs were jusyt
temperature related.
5)We also got reports that some of the instructions in the Hall C ops manual were
inconsistent possibly leading to operator error type problems.This is being checked
and any errors will be corrected.
Specifically the instructions for polarity reversal may be inconsistent.
The HMS Dipole does polarity reversal automatically.Just select the polarity on one
of the power supply control screens and wait.The dipole system will ramp down ,
wait , reverse and then ramp back up.
For the Quads just set the current to zero.Then set the polarity . Then reset the
current.
The commands for restarting the PC's if you get stuck on a DOS screen are
"HMS" for the dipole and " CEBAF " for the quads.
The manual will be edited.
Thanks
Paul
Dave Mack wrote:
> *******************************************************************************
> PRELIMINARY (AND ONLY) AGENDA FOR THE
> REGULAR HALL C MEETING 3PM MONDAY (L104)
> no speakers have been confirmed
> *******************************************************************************
>
> I. General Roger Carlini
>
> II. Spring '99 Experiments
>
> report from d(g,p)n Al Nathan
>
> report from A(e,e'p), etc. Rolf Ent
>
> III. Upcoming experiment updates:
> HNSS, Sick, Zeidman, Gen ??
>
> IV. G0 Update Allison Lung
>
> V. Energy Fest Paul Gueye
>
> VI. Any Other Business
>
> --------------------------------------------------------------------------
> Chris Armstrong submitted an updated version of his paper to PRD.
>
> I put a list of Hall C papers and Ph.D. grantees on the Hall C web page.