Calibration on the iGen4

I'm new to this forum so don't shoot me if i'm posting something that already exists I have searched for it but the threads that I saw didn't answer to my question.

I'm a student who is just started the training period to eventually graduate this year. My assignment in the company: color management on the iGen4.
We use the Freeflow Server system.

I have a big question about calibrating the machine: the only thing we do to calibrate the machine is 'TRC engine linearisation'. Profiling we do with X-Rite's i1 iSis chart reader and a fogra 39 chart (software is Colorport)
Is there a better way to calibrate the machine than the TRC engine linearisation?

 

TRC Lin is the only way to calibrate the machine internally, but it really should only be done when the Color Management Tool requires it, or one of the maintenance procedures requires.