Remote Starting an Agilent 6890N

[pfloyd]

Hello,

Basically, I want to remote start my GC using a control program independent from the chemstation software. We have an older model that required the use of a contact closure on what I believe is the APG cable. Is it correct, that the 6890 models can remote start/stop using a TTL signal, and if so, is this done over one of the communication cables, or is the voltage applied directly to the main board. Any help regarding the location and any other specifics would be greatly appreciated.

In addition, any information about good source material for the Chemstation Macro Language is also welcome.

Thank you

[pfloyd]

Since I haven't received any answers to the original question, I will ask if anyone has had any experience with program interfacing with the ChemStation software.

It occurs to me, that there are two ways of remote starting the GC from an external program without having to actually stand there and push the start button on the front panel, or enter a command on the command line. One way is to send a TTL signal to a specific pin. I am not sure whether this needs to short to ground, or whether I apply 5 volts. Furthermore, I am not sure where exactly I need to wire in. Another possibility is to interface my program with the ChemStation, in order to send a start command over the network directly to the GC. Once again, I am not sure how exactly to go about doing this. Any help with either one of these possibilities is greatly appreciated.

Thank you

[Steve Reimer]

This sounds like the normal control for a purge and trap system. In my case an OI 4560 or 4660 sends a contact closure signal to the GC to start. It also is looking for a ready signal from the GC.
If you don't want to set up an electrical switch and use a software solution you may need to simulate the keyboard start command.

[pfloyd]

I think that I have it figured out. See, we are running an Agilent GC/MS system with models 6890N and 5973N. On the back of the GC there are a number of different connectors for functions ranging from sampler communications to analog signals outputs. Referring to Agilent document 1215 External Connectors, 6090N, there is only one APG remote connector. Since we are running it with an MS, this connection is already in use. I wasn't quite sure where the cleanest place to wire in would be, nor what type of logic was necessary. The pinouts for the APG remote connector are as follows:

Pin 1: Digital Ground
Pin 2: Prepare
Pin 3: Start
Pin 4: Start Relay
Pin 5: Start Relay
Pin 6: No connection
Pin 7: Ready
Pin 8: Stop
Pin 9: No connection

For remote starting the GC, the logic for prepare, start, and stop inputs are low true, while the ready output is high true.

Agilent also sells a Y-cable for $170.00. This cable should allow me to connect to the MS from the GC and send start/stop signals from a computer to a digital I/O board, to a relay, and then to the GC, which will also remote start the MS. Now all I really need to do, is wait for the part and wire it up when it gets here.

Thanks for the response, Steve. Reading a ready signal and applying a contact closure based on the answer is exactly what I am going to do.