I thought this might be another solution to consider for people who encountered this problem: Similar to Sara and others, I had the exact same problem with our Inova-500 a few years ago. I just bought a serial cable used for computer devices and made the connection between the probe and the original VT cable. I then fixed the end portion of the original VT cable and its connection to the serial cable to the magnet leg using a few cable ties to prevent any movement or stain to the VT cable. The computer serial cable is very flexible, and as far as I know, we never had VT problems since then. I initially worried about possible issues with shielding in using the computer serial cable under the magnet, but the spectra seem to be perfectly fine, so I guess that is not a problem.
Best regards,
Wei Li
--------------------------------
Wei Li, Ph.D.
Associate Professor/Faculty Director of Instrument Facility
University of Tennessee Health Science Center
847 Monroe Avenue, room 327
Memphis, TN 38163
901-448-7532 (PH)
http://www.uthsc.edu/pharmacy/pharmsci/faculty/wli/
Email: wli_at_uthsc.edu
-----Original Message-----
From: Sara D Kunz [mailto:kunz_at_brandeis.edu]
Sent: Tuesday, March 19, 2013 1:44 PM
To: Stolowich,Neal J.
Cc: ammrl_at_ammrl.org
Subject: Re: AMMRL: VT controller has no gas flow
Several years ago, after a lot of frustration with Varian VT cables, I decided to support the VT cable so that it would not hang down putting stress on the connector and to keep it out harm's way. I wrapped a bungee cord around one of the magnet legs and arranged the VT cable under the cord on the inside of the magnet leg and then connected it to the probe. There was no longer any stress on the connector and the cable is was out of the way. I no longer get calls that are related to the VT controller.
Sara Kunz
Brandeis
On 3/18/2013 2:16 PM, Stolowich,Neal J. wrote:
>
> I have noticed this a couple of times on my VNMRS 700 as well. A few
> cycles of resetting the VT and pneumatics, perhaps with rebooting the
> console in between does fix it, but I'm curious as well if there is a
> specific fix, rather than randomly resetting things.
>
> Regards,
>
> Neal
>
> Neal J Stolowich, PhD
>
> NMR Facilities Manager
>
> Department of Chemistry
>
> University of Louisville
>
> *From:*Xuemei Huang [mailto:xhuang_at_ucsd.edu]
> *Sent:* Friday, March 15, 2013 7:26 PM
> *To:* ammrl_at_ammrl.org
> *Subject:* AMMRL: VT controller has no gas flow
>
>
> Hi, Everyone,
>
> We have a 800MHz Varian VNMRS spectrometer equipped with cold probe.
> Recently I am running into a problem where I can not regulate the
> temperature. After I set the temperature, I see the VT starts
> flashing, indicating it's trying to change the temperature. But the
> temperature never changes. I tried to reset the VT controller, the
> pneumatics, as well as resetting the console. None of them seemed to
> solve the problem. The error message I am getting is that : VT
> controller has no gas flow. But I checked that there is sufficient air
> flow. Has anyone seen similar problem on this system? Any suggestions
> would really be appreciated.
>
> Thanks,
>
> Xuemei
>
> ***************************************************
>
> Xuemei Huang
> Department of Chemistry and Biochemistry University of California, San
> Diego
> 9500 Gilman Dr.
> La Jolla, CA 92093
> xhuang_at_ucsd.edu <mailto:xhuang_at_ucsd.edu>
> (858)-822-2307
> ***************************************************
>
>
>
>
Received on Wed Mar 20 2013 - 08:55:12 MST