GE Mark VI, 7FA dual-fuel unit, Emergency Transfer function?

What are the differences in the process of transferring from gas fuel to liquid fuel (and vice-versa, I suppose), when enabling "Emergency Transfer" on the Mark VI? I've gone through what manuals we have on-site, and cannot find anything specific. Any guidance would be greatly appreciated!

The OEM has implemented a number of different schemes for ensuring (or trying to ensure) a reliable and quick fuel transfer. You really need to contact the OEM and give them some information about the control system and software versions and any special systems (such as a liquid fuel recirculation system) and ask them for how your particular system should operate.

OR, you can work through the application code running in the Mark VI to see what happens when you click on the HMI button to enable "Emergency Transfer"--which is really about the best and fastest way to understand precisely what is supposed to happen at your site. Using the P&IDs and working through the application code is really and truly the ONLY way to know exactly what's supposed to happen at YOUR site.

Have you looked through the various system tabs of the User & Service Manuals provided with the unit for any information? Those are usually very generic, but can usually provide the basis for understanding what's supposed to happen (the intent of the system, though usually NOT the specifics or your systems and their precise operation).

Another reasonably good written resource is a document called the "Control Specification." It may have some specific documentation that was written at the time the unit was configured and delivered to site to explain what might happen at your site.

And, finally, working through the Mark VI application code there will likely be some comments in the software which can be helpful--just DO NOT expect all the comments to be specific to your machine (there are a lot of "artifact" comments in Mark* application code which should have been removed to prevent confusion--but weren't).

But, short of contacting the OEM (if you have an LTSA and CSM they can be helpful, once in a while) for details, or, again, the best route--working through the Mark VI application code running in the Mark VI at your site in conjunction with the site P&IDs (what GE calls the "Piping Schematics" or "Schematic Piping Diagrams") that's about it if you can't find anything in the manuals provided with the unit that is helpful.

Sorry; someone here with a similar configuration may be able to help you, but, I personally do not have any experience with one of these fast fuel transfer systems--but I do know there have been multiple iterations of them over the years. Some were installed after the unit was originally commissioned, and so the accompanying documentation probably didn't (usually doesn't) make it into the Manuals provided with the unit.
Thanks for the info, CSA! Unfortunately the Control Specification didn't have the info I was looking for, so I'll see if I can get our techs to take a peek into the application code, us guys on the desk don't have access to that.