I have a Mori where there is a toggle switch inside the electrical cabinet that says Bar Feed Valid/Invalid. I'm guessing you're not going to be so lucky.
All the bar feed contactors and relays etc are likely going to be grouped together somewhere. If you have any knowledge of electrical circuits you should be able to go through the manual and figure out where you need to go to lie to the computer.
For instance. There may be a motor overload with an ON/OFF rocker switch. Likely on that switch is a NC (Normally Closed) contact that when the switch is on (as it would be normally) the switch becomes Open, and therefore the control thinks everything is okay. But when you manually turn that switch off and close that contact, it sends a signal to the computer that the motor is overloaded and alarms out the machine. All you'd do in this case is simply disconnect one of the wires going to the NC contact area of the overload. FYI - the above scenario could easily be the reverse (contact type wise) of what I just suggested. It's also possible you will also have to jumper the Emergency Stop circuit. Emergency Stop Circuits are almost always big long daisy chain circuits. Meaning a long Series circuit. Any break in the circuit anywhere sets of the Emergency Stop. Find where the E-Stop on the bar feeder is connected, and jumper those connections.
Whether there is a parameter or not to disable the bar feeder may be hit or miss. Perhaps someone will chime in with the magic bullet you're after. If not it's these kind of computer fake outs that will get you where you want to go.
It might actually be a Keep Relay that turns the Bar Feed on and off. If you have all the manuals, look through the Keep Relay or Data Tables. It may say right there, Bar Feed Valid set this. Bar Feed Invalid, set that.
Seeing as you're new to Fanuc. Watch this Youtube video. It will fill you in on a lot of things in a hurry.
Good luck with your new machine.
https://www.youtube.com/watch?v=FvezGLI_dxg