Subject: Re: 2.5m obslog 20100608 (MJD 55356)
From: Wendell Jordan
Date: Wed, 9 Jun 2010 09:40:02 -0600
Connie,
I did a couple of startfillseq commands to sp1 and sp2 alternately.  Sp1 =
does NOT do the added "timed insurance fill" following its initial fill, =
however sp2 DOES give the added "timed insurance fill" following its =
initial fill.  Liquid LN2 does spew out during sp2's insurance fill, but =
liquid LN2 does not spew out of sp1 cameras that I could see (just the =
gas).  Again, sp1 does not do an insurance fill--Could this lack of =
timed insurance topping off be part of sp1's problem?
Both sp1 camera valves seem to behave correctly during commanded fills, =
and turn off within several seconds of one another.  I still plan to do =
a coil resistance check however.
Wendell
On Jun 9, 2010, at 8:35 AM, Constance Rockosi wrote:
>=20
> Looks like sp2 red got its ln2 dumped out. =20
>=20
> David -- you are correct about the dictionary error.  But
> to really answer you question I need to know where the data
> comes from. ln2check, tcheck, or showreadvolts?
>=20
> --connie
>=20
> On Wed, Jun 09, 2010 at 07:31:07AM -0700, David Kirkby wrote:
>> The SP2R0 LN2 temperature is spiking right now but was fine earlier =
(see the
>> attached plot of LN2 temps over the past 3 days). Is that expected?
>>=20
>> The BOSS dictionary claims that it reports LN2 temperatures in Volts =
but
>> that doesn't sound right looking at the graph.
>>=20
>> David
>>=20
>> On Wed, Jun 9, 2010 at 4:40 AM, Constance Rockosi =
wrote:
>>=20
>>>=20
>>> There is some padding that lets the CCDs warm up a little bit before
>>> you get a temperature error, so I am not very worried that you =
didn't
>>> get a temperature error.
>>>=20
>>> You should have gotten a fillfault error.  Did you?
>>>=20
>>> Ah. If you didn't, then that might be telling us that the problem
>>> is that the full sensor has failed open, so that the camera micro
>>> always sees the dewar as full.
>>>=20
>>> --Connie
>>>=20
>>>=20
>>=20
>>=20
>> !DSPAM:10028,4c0fa5ad5231021468!
>=20
>=20
>=20
> --=20
>=20
> Associate Professor, Assoc. Astronomer
> UC Santa Cruz, UCO/Lick Observatory
> Office: 831 459 5246
> crockosi@ucolick.org
> http://www.ucolick.org/~crockosi
>=20
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