The IOHC3500 horizontal machining center of my company was 1985 by the United States dragon company introduces Xinxinnadimilake. The mechanical performance that considers this machine tool is good, choose advanced FANUC 0i, system of MA numerical control undertakes machine tool electrical system is transformed. It is good that after this machine tool is transformed, a year of amorous Kuang Liang is used. But appeared often nearly in March X axis exceeds coordinate of machinery of axis of Cheng, X to be worth the breakdown such as unusual, flying car. Because X axis is gear rack drive, so X axis uses complete closed circuit linear model grating feet feedbacks. When switching on the mobile phone now and then appear (POS picture) value of coordinate of X axis machinery is lost ceaselessly to increase, occurrence 501# , X axis loses Xiang Chao Cheng, 401# , the give an alarm such as OFF of buy of X position of axle, press irrevocable give an alarm of DEL + CAN. The lamp of LED give an alarm of CNC/SERVO face plate did not shine. But actual machine tool is in stopping axis of the X below condition urgently cannot move. Enter (SVPRM) servo adjusts a picture, observe current position and positional deviation are in negative to increase, with opportunity bed occurrence 501# , X axis loses give an alarm of Xiang Chao Cheng (exceed 132# , 1320# parameter set is worth) . Close machine is new the machine tool that start, coordinate value stops X axis machine in some on very great random value. Axis of X of this opportunity bed cannot be answered at 0 o'clock, it is normal at 0 o'clock that the servo axis of other is answered. Value of coordinate of X axis machinery looks to exceed Cheng really on numerical value, actually the machine tool is inside X axis limits. Enter parameter set picture to revise 1321# , 1320# parameter (the coordinate of the negative direction border that X axis stores type journey detects is worth) . Value of indication coordinate of X axis machinery exceeds far - 99999999 ～ + 99999999 limits (unit μ M) . Right now but set coordinate is worth NO, 1320# is less than 1321# to be lost namely be more than to the value to the value, can make this function makes can. Close machine is new the machine tool that start, x axis can be answered at 0 o'clock. 132# , 1320# parameter is reductive, the machine tool can work normally very long period of time. As a result of this breakdown now and then appear, consider as external power source is high frequency interference, add in each loop then packed return circuit of wave of interference rejection filter. To eliminate the possibility of software breakdown, count all sorts of ginseng of backup data refresh. But breakdown is before long more and more frequent, mobile X axis is moved with the dot no matter, the hand is moved time 0, x axis is met fast impulse or acuteness and asp, 411# of give an alarm appears on CRT, the positional deviation quantity in shift is more than set value, the most serious when of flying car inertial bump into the mechanical link stopper of X axis, all but develop a slideway. Be occurrence breakdown of speed annulus or positional annulus and feedback source after all? This breakdown appears in X axis merely, and only X axis is full closed-loop control. Because X axis is the same as fashionable dress to have,rotate pulse coder, break up annulus of annulus of grating feet position, pulse coder position for this, in order to determine systematic breakdown position, modification parameter X axis by instead of full closed-loop control half closed-loop control. Modification method: In park position urgently, receive electrify source. First parameter of set adaptable system, parameter 3111#7(SVS)=0 enters the set picture of servo parameter, can alter control position of the axis. Modification content is: (1) is flexible feed gear is compared (N/M) feedback of feet of grating of complete closed circuit is 1:1, the according to electric machinery decelerate when half closed circuit decides than coming set is worth, new set value is 1:1Number of pulse of 2500 (2) position wants to decide according to the model of serial pulse coder, the set value of this machine is 6340. (1815#1=0 of parameter of type of 3) position feedback (1 complete closed circuit, 0 half closed circuit) . Close machine is new set of above of the machine tool that start is effective, the machine tool is normal. Gap of the backlash as a result of drive of rack of X axis gear, gear is bigger, short of precision asks, can run an operation merely. But it is normal that half closed circuit can show electric machinery of CNC system, driving unit, servo normally. Check grating feet or the circuitry related to this, the LB that this grating feet is FAGOR company, 3650mm is linear model feet of reflection type grating. Minor failure is grating feet: Have between the scale that change rule smeary bring about pulse leakage pace to make CNC cannot sequence of appearance of normal computation, A, B identifies have by accident, break a line to wait. Out of tolerance of precision of the geometry between the scale that change rule also can make reading window and reflection metal tape have displacement, influence reading. Examination feet cable the outlet of two end. Will measure cable to be reached from CNC move the depart on feet, shake with 500V the watch measures cable between, be isolated from between cable and screen layer. With avometer one by one the examination measures every cable to whether have the appearance of open circuit, move back and forth with different speed whether does head of watch of X axis observation have shaken appearance. The phenomenon that if have,shakes has with respect to demonstrative cable somewhere break off be like a blame to connect. Did not discover a problem through the examination. Next electrify are checked, let X axis move back and forth with different speed. The phasic difference of photograph of the circumstance that can observe with oscillograph whether every photograph has leakage pulse so and A, B has 90 ° , if conditional, with what have memory function oscillograph can observe a few more meticulously. Every photograph strings together a Gao Liang LED and 50052 resistor, with handwheel inch X the axis can see LED of photograph of A, B twinkle alternately. N of oscillograph observation discretion is worth (3V ～ 0. 5V) whether to have change. Through above the examination of a few respects all normal, reason can eliminate the possibility of the breakdown of out of tolerance of precision of grating feet geometry and relevant circuit. The question may happen on the hardware interface of CNC, can pass breakdown of mouth of butt joint of interface of crossing-over of modification system parameter to undertake affirming right now. The position of partial hardware interface pursues as follows. Enter an axis to define parameter, 1023# SERVO AXIS NUM X axis instead 4, B axis instead 1. Give axis of X, B signal cable exchange, pursue namely 1 in Senvol mouth and Senvo4 mouth crossing-over. X axis signal of feedback of linear grating feet receives Scale 4 mouth from Scale 1 mouth, change the machine tool a full closed-loop control. Switch on the mobile phone to start a machine tool afresh, everything is normal. Restore savagery breakdown emersion, return modification condition again, the machine tool is normal. Take an examination of breakdown of machine a week to did not appear again, can explain mouth of systematic Scale 1 damages from this. Change right now circuit board, changing board before should all sorts of parameter the machine tool (grand variable, cutting tool compensates compensating parameter of CNC parameter, PMC parameter, pitch, user graph of value, echelon, machine program) in passing a PC entirely, save. Notice the integrality of data certainly. If have primitive backup data better. Transmit a few times back and forth between CNC and PC with PCIN, V24, FAPT LADDER affirm without by accident hind, wear ground connection bracelet to be able to undertake changing board. Change end, switch on the mobile phone to back up memory data is passed in CNC entirely, restore savagery, open motive bed, the job is regular. CNC Milling