Proper setting of a magnetic trip breaker
15x FLA is not at all unusual with modern energy efficient motors. This is not STARTING current, this is MAGNETIC INRUSH current that flows only for the first cycle (at most) as the magnetic flux is created in the motor windings and core. For that first cycle, there is no mutual induction yet, which is what accounts for impedance. So initially, the only thing impeding the flow of current in each coil is the very low resistance of the copper wire itself; it is in essence a "short circuit" for that instant. 

As motor mfrs were required to improve energy efficiencies in the 1990s, one way they reduced I^2t losses in the motor was to reduce the coil winding resistances. That resulted in much higher instantaneous magnetic inrush currents. THAT is why the NEC allowed for the increased values starting a few years back. But many older textbooks and even some newer on-line resources have not adequately kept up with that change in design philosophy, leaving people confused as to why older setting rules seem to no longer work. 

Bottom line, don't worry about it.