[FFAMN]

I own a PCNC with a 5 hp HSD 3 Phase spindle. Recently the x axis has begun to creep to the right when the spindle is on. I believe this movement is do to the torque of the spindle. Any ideas on why this is occuring?

The shaft of the X axis servo motor is turning. Thus do I have a failure of the encoder or servo motor?

I do appreciate any words of wisdon.

FFAMN

[FFAMN]

The problem we have been having with X axis creeping when the spindle is running appears to be multi factorial. We recently isolated the ethernet 'encoder" cables for all axis away from the power supply cables. The creeeping stopped when cutting 1/4 plywood but returned when heavier material was used. Thus, we are beginning to think it may be an either an encoder or servo controller issue. The creep is always in the direction of spindle rotation (torque). Either the encoder or the controller is not seeing or holding the movement caused by this rotation.

[ger21]

Are you sure your not getting noise in the encoder lines?

[FFAMN]

Gerry,

Thank you for your feedback.

Yesterday we installed three new 14 foot long ethernet lines from each encoder on each servo to the servo controller. Before,we were using the 50 foot lines PCNC had equipped the machine with. The original lines were run within two energy chains along side the 220V 3 phase power supply. In addition, the extra length was bundled up using plastic wire ties. We speculated the closeles of the encoder lines to the power line as well as bundling them up ( they are shielded lines) was resulting in noise in the encoder lines. Thus the installation of the short 'patch' lines to see if we could elminate the creeping. We made a subsantial reduction is the creeping but still have a little left. Thus, we will be checking ought the encoders with a scope to see if they are reading the movement. If they are, the we will check into the servo controller to see why it is not responding to the axis movement.

Steve