Motor circuit ground

[retire09]

I have a plan showing 12 AWG conductors on 30 amp breakers feeding motors.
They also have 10 AWG 90 degree rated conductors on 100 amp breakers.
They have convinced me that this is allowed per 430.52 with inverse time breakers but don't the grounding conductors still have to match the breakers per 250.122?
Need a minimum of a #10 for the 30 and a #8 for the 100 amp breaker?

 

[don_resqcapt19]

See 250.122(D) for the sizing of EGCs used with motor circuits. Note that 250.122(A) also applies.

 

[retire09]

Motor circuit ground

Is this a conflict with 250.122(A) "but in no case shall they be required to be larger than the circuit conductors supplying the equipment"?