3017 Spindle motor drawing excess current for <5sec.
Sheet 4 Plug 2 Pin-A
This error will display if the load on the spindle is high for less than 5 seconds, during which time the programmed feedrate will be reduced to ease the load. 

a) Check the condition of the cutter in use at the time of the error and that the programmed speed and feedrate are not too high for the cutter and material.

b) Monitor the spindle load meter whilst machining; if the load meter keeps below 100% and the 3017 error displays on the control, then the 'Excess Current Detector' needs adjusting (Pot 4 on the detector unit facia). It should be set at about 60%.