[Esr-users] Halls B and C today

[Dave Kashy]

Hi Paul,
The UPS's that we are changing out provide backup power to our PLC's so we will run blind  and w/o PLC control during each UPS swap and there are 4 units.
We will do our best to limit the bump size, but no garantee that you will not see a bump.

Dave


----- Original Message -----
From: "brindza" <brindza at jlab.org>
To: "kashy" <kashy at jlab.org>, "esr-users" <esr-users at jlab.org>
Cc: "rossi patrizia" <rossi at jlab.org>, "Rolf Ent" <ent at jlab.org>
Sent: Thursday, November 2, 2017 9:17:24 AM
Subject: Hall C today

Hi

We will be doing magnetic field measurements on the HMS Dipole today.
We have to acquire a full B vs I curve thru the entire range of the 
Physics run 1000 Amps to 2800 Amps with a "locked on" NMR.
System stability will help a lot because this operation is extremely 
intolerant of even the smallest fault.
A failure of the NMR to lock at any point invalidates the entire data 
set and you have to start over.
A magnet trip for any reason during this process will necessitate a do over.

HB retrained up to 3665 Amps yesterday without incident and no further 
retraining runs are planned any time soon.
This run was to confirm that there were no ill effects of removing a 
piece of unexpected magnetic material.(see below)
We will have to revisit the retraining at some point because we have not 
surpassed the 11 GeV current but we are past requirements for the winter 
2017/18 Physics run.

HB beam line stray fields will be remeasured this week  probably 
starting Friday.
This is necessary because we removed a magnetic bracket that was part of 
the installed field clamp but not in the TOSA model and it had an effect.

Some further magnetic measurements on SHMS Q2Q3 and Dipole are likely in 
the very near future.

Hall C continues to hunt down and repair CVI valves that are past their 
"use by" date.

Cheers

Paul