After many years of service, we too had to replace the Mini-IMG with an FRG-700 - please see attached for instructions that Agilent sent regarding the pin outs from the RJ45 to DB9. Best regards, Sean
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Sean Cahill, Structural NMR Resource
Albert Einstein College of Medicine
http://www.einstein.yu.edu/home/faculty/profile.asp?id=477&k=
From: Jacobsen, Neil E - (neil) [mailto:neil_at_email.arizona.edu]
Sent: Tuesday, September 22, 2015 8:00 PM
To: ammrl_at_ammrl.org
Subject: AMMRL: Replacement vacuum gauge for Varian Cryogenic probe system
The question is: what is the make and model of the vacuum gauge controller in the CryoBay? Here is the long story leading up to it:
Our Eyesys mini-IMG gauge, which is attached to the Mini-Task vacuum pump that pumps continuously on the probe, no longer works. The vacuum reading jumps all over the place. We took it apart and cleaned the transducer (there was a serious coating of corrosion) very thoroughly, including sonication, but this didn't fix it. We sent it to Ideal Vacuum Systems for evaluation and they said there is no replacement transducer available, so we need to replace the whole gauge.
They recommended a new Varian FRG-700 full-range gauge to replace it, but the data connector on this new gauge is a phone-jack type data connector (8 poles FCC-68), just like a network plug on a computer. The old gauge has a 9-pin mini-serial port connector. So to see if the new gauge will be compatible with our CryoBay, the engineer at Ideal Vacuum System wants to know what is the controller that the gauge connects to. We followed the cable into the CryoBay and it disappears into a metal box that has all the pneumatic control lines as well as cables coming from the pressure sensors in the cold head. Coming out of this box is a ribbon cable going to the CryoBay computer. I can't open the box without warming up the probe.
So I'm wondering if anyone knows what is in the box connecting to the vacuum gauge? Also, since the proposed replacement gauge is a full-range gauge (760 torr to 3.8 x 10-9), will the CryoBay be able to read pressure all the way up to atmospheric? As far as I know, the old gauge only had the single range (10-3 torr to 10-9 torr).
These are some pretty obscure and specific questions, but I'm always amazed at what people know in AMMRL.
Thanks for any information and help,
Neil
Received on Wed Sep 23 2015 - 03:17:48 MST