Yesterday after a nitrogen fill, and today during the first part of a
helium fill, I noticed a strange hissing sound which appeared to be
coming from our R2D2 magnet of our Varian Gemini 200 MHz instrument. It
was a hissing sound with almost a reverberation, like either wind
blowing through a tunnel or LN2 when it's just been put into a warm lab
dewar. No plumes were coming from the stacks. My first instinct was to
look around and see if it could be coming from the air handlers instead.
Each time the "blowing" sound lasted probably less than a minute.
In both cases, a follow-up check after the fact showed that helium and
nitrogen boiloff rates were normal. Air flow to the spinner and the
spinner rate was normal (after the fact). The lock signal was normal.
The instrument does not have VT capability installed.
The instrument (1990's vintage) was installed here in June by a Varian
representative.
Has anyone else heard this type of sound coming from their magnet?
Ruth
Ruth E. Nalliah, Ph.D.
Huntington College
Huntington, Indiana
(260)359-4203
rnalliah_at_huntington.edu
Received on Thu Dec 11 2003 - 16:20:15 MST