[Dlsupport] task list 06/28/2016

[David Douglas]

Yes, once we figure out what the answer is... this is a really good idea 
Michele...

Based on what we found with the 5 quad rotator in the IR Upgrade driver, 
it is our present understanding that the sense of the rotation of the 
skew quads is opposite in installation/EPICS and the optics codes. We 
need to verify it. Once we know the sign(s), we can and should record 
them! Basically, the skew QX quad set points have differed in sign on 
the machine from those in the codes to achieve the same answer. Or maybe 
not, depending on the code, and the sign of the rotation used in the code.

The plan is to turn off all but one of the skews, steer down and right 
(outboard from the interior of the ERL) and see what way the beam goes. 
If the rotation is clockwise looking from behind the quad in the 
direction of beam propagation, a positive skew quad will deflect the 
beam inward and upward - if I have the signs right... ;)

I don't know off the top of my head which way the code(s) will deflect 
things, but we'll check!

Thank you!

D




On 7/6/2016 10:59 AM, Michele Joyce wrote:
> Should this info be kept and maintained in the LED?
> Michele
>
> On 7/5/2016 12:26 PM, David Douglas wrote:
>>
>> Thanks Jim.
>>
>> Part of the need for the polarity check is to establish the "parity" 
>> of the skews (which differs between EPICS and codes). I don't want to 
>> introduce bias, but if we could measure the poletip field (with sign) 
>> of each quad and log it, we'll save time overall. I'll sketch up a 
>> procedure.
>>
>> Thanks
>>
>> D
>>
>>
>> On 7/5/2016 11:00 AM, Jim Coleman wrote:
>>> Hi Dave,
>>>  We haven't powered any of the 4F quads yet.  That will not happen 
>>> until the spool pieces are installed due to splitting of the magnet. 
>>> We have to perform a voltage/ current/ polarity measurement of any 
>>> magnet as part of the HCO.  I'll make sure LCW gets put on the skews.
>>> -Jim
>>>
>>>  On 7/5/2016 10:08 AM, David Douglas wrote:
>>>>
>>>> re: #2) - please put the results of the test into the LERFLog. Thanks
>>>>
>>>> D
>>>>
>>>>
>>>> On 7/5/2016 10:07 AM, David Douglas wrote:
>>>>>
>>>>> Hi Jim - don't know if the following was communicated to you or 
>>>>> not, but
>>>>>
>>>>> 1) Steve asked if the 10 additional skew quads needed water 
>>>>> cooling. Answer: if the other quads are run with water cooling, 
>>>>> these will need it as well. They run at the same fields as the 
>>>>> normal quads.
>>>>>
>>>>> 2) Has each quad been polarity checked (i.e. a Hall probe put on 
>>>>> each pole of each quad)? We need to be sure there are consistent 
>>>>> sign conventions through 4F, and I'll need to know what pole of 
>>>>> each quad is at what sign and field level when the usual +5A test 
>>>>> current is being run.
>>>>>
>>>>> Thanks,
>>>>> DD
>>>>>
>>>>>
>>>>> On 6/30/2016 4:32 PM, Jim Coleman wrote:
>>>>>> apologies for sending it out late
>>>>>>
>>>>>>
>>>>>>
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