Re: humidity sensor (fwd)

[Claude Petitjean <claude.petitjean@psi.ch>]

lieber Peter,

ich bin jetzt gerade auf dem Sprung nach Russland für die
nächsten 2 Wochen, kann den humidity devices erst nachher
nachgehen,

mit lieben Grüssen

Claude

Peter Kammel wrote:

> Lieber Claude,
> 
> Ich habe nochmals Sacha et al. angefragt, ob wir etwas bei der HS
> Auslese uebersehen haben, welches den Factor 2 zu Francoise
> erklaeren koennte.
> 
> Natuerlich antwortet er mit seinem Kalibrierungsplan. Bevor wir
> aber dies weiter ueberlegen, koenntest Du bitte mit der
> Firma in Wettingen sprechen, was diese anzubieten haette.
> Unser Wunsch waere eine chilled mirror calibration vor dem
> Run und dann eine direkte Messung von ~15 ppb waehrend
> unserer Messung.
> 
> Die Information dazu findest Du in Bernhard's email
> http://www.npl.uiuc.edu/exp/mucapture/coll/mail/msg01050.html
> 
> Wuensche ein schoenes Wochende
> 
> Peter
> 
> 
> 
> 
> ---------- Forwarded message ----------
> Date: Fri, 3 Nov 2006 10:21:11 +0100
> From: Alexander Vasilyev <vassilie@mail.pnpi.spb.ru>
> To: Peter Kammel <kammel@npl.uiuc.edu>
> Cc: Marat Vznuzdaev <marat@mail.pnpi.spb.ru>, Peter Kravtsov 
> <pkravt@gmail.com>,
>     Brendan Kiburg <kiburg@npl.uiuc.edu>,
>     Francoise Mulhauser <Francoise.Mulhauser@psi.ch>
> Subject: Re: humidity sensor
> 
> Dear Peter,
> 
> We discussed humidity many times and there are many opinions. We spent for
> the discussions much more time (and money!) then necessary for the precise
> measurements in our real conditions - 10 bar of hydrogen, few liters per
> minute flux and our range
> of humidity.
> We have options:
> 1. Send humidity sensor to the firm for the calibration in real conditions.
> 2. Borrow "mirror" technique and use in PSI for the calibration in our
> conditions.
> 3. Create the "known" humidity by the cryo technique (proposed by me) and
> calibrate HS.
> 
> We checked few times calibration curve. We used different sources for the
> dependence - humidity - dew point and the differences are not bigger then
> few %.
> We checked few times conversion current signal to the number on the 
> "screen"
> and this conversion is OK.
> We have to check again to exclude the "stupid mistakes" but probability of
> it is low.
> 
> With best regards   Sasha.
> 
> 
> Vasilyev Alexander
> 
> Petersburg Nuclear Physics Institute,
> Laboratory of Cryogenic and Superconductive Technique.