Chromatography Forum

Hi everyone,
I am currently working with a Varian 3400 GC and was hoping to automate method changes by connecting it to a program running on a PC. I have access to the S I/O and DET boards and have tried plugging an IEEE-488 to 24-pin D-sub connector. This was just a cable we had in lab and not the V3400-CBL cable.

My questions are:
1. Will this cable work and if not, is there any way for me to adapt it to make it work?
2. Does anyone know the command codes to control a Varian 3400? Is it even possible to do this?
3. What programming software is best for this job?
4. Am I missing anything important?

Thank you so much for your time and efforts.
Sean

An approach I have used which may or may not be helpful:
We used a DAQ hardware box that was compatible with the software (turbochrom, now totalchrom) we were using. The DAQ box had the ability to control relays, which we used to run solenoids and pneumatic valves, which let us control method start, sample purge/injection and column switching. However, we were not able to modify the method, such as temperature zone settings or TCD current. We could switch easily between the four programs that the 3400 is able to store, but a custom program would have to be entered by hand every time. The sequence table also had to be entered by hand.

3400s are getting pretty old; it may be hard finding a better solution. Good luck!

A software to control the 3400 is the Magnum Software 3.0 from Finnigan. It's just 20 years old and only runs on native MS-DOS.

One would have to decipher the serial protocol and implement it in a modern programming language of your choice that can transmit and receive data over the serial interface.

If this is not an alternative to you, I'd go for what aidnai recommended. It's the way we're running our lab at the moment (besides the Magnums/ITS 40 MSs).

On a side note, I've done lots of reverse engineering and never had the need to actually look at the 3400's serial protocol. I guess it's rather straight forward, but knowing the dark nightmare of brain fungus formelry known as Varian, it can also be some steaming pile of binary junk. One'd have to look.

Regarding your cable, I have my doubts it'll work. To be precise, I guess you're doing it wrong as the 488-like end should be plugged into the serial card of the 3400.