run away 2:
Check for loose or broken couplings with encoders or resolvers, check power supplies and connections with encoders or scales, check for broken or loose wiring, lastly check feedback signals with an oscilloscope.
If there still is a problem, swap RDC1732 (resolver feedback) or encoder feedback daughter card on Servo Board (only blue board in rack) for the axis that is running away with one that is known to be operating correctly. On the Servo Board with the edge connector to the right, going from top to bottom, the axis order is X, Y, Z, and HANDWHEEL .
formerly Incon Systems Limited