Haas Vf-series User manual

1-15-96 96-8100 1

TABLE OF CONTENTS

HAAS AUTOMATION, INC.

TROUBLESHOOTING

SERVICE

MANUAL

VF-SERIES

TROUBLESHOOTING

This section is intended for use in determining the solution to a known problem. Solutions given are intended to give the

individual servicing the CNC a pattern to follow in, first, determining the problems source and, second, solving the problem.

The troubleshooting tips are organized in this section according to the area of the CNC that may be giving sign of a problem.

(Ex.: Out-of round circles in drilling will be found under the heading General Machine Operation - Accuracy).

If the problem you are experiencing cannot be found under the heading you expect, please try several other possible head-

ings. If the problem is still not found, contact Haas Automation for further details.

BEFORE YOU BEGIN:

USE COMMON SENSE

Many problems are easily overcome by correctly evaluating the situation. All machine operations are composed of a

program, tools, and tooling. You must look at all three before blaming one as the fault area. If a bored hole is chattering

because of an overextended boring bar, dont expect the machine to correct the fault. Dont suspect machine accuracy if the

vise bends the part. Dont claim hole mis-positioning if you dont first center-drill the hole.

FIND THE PROBLEM FIRST

Many mechanics tear into things before they understand the problem, hoping that it will appear as they go. We know this

from the fact that more than half of all warranty returned parts are in good working order. If the spindle doesnt turn,

remember that the spindle is connected to the gear box, which is connected to the spindle motor, which is driven by the

spindle drive, which is connected to the I/O BOARD, which is driven by the computer. The moral here is dont replace the

spindle drive if the belt is broken. Find the problem first; dont just replace the easiest part to get to.

DONT TINKER WITH THE MACHINE

There are hundreds of parameters, wires, switches, etc., that you can change in this machine. Dont start randomly changing

parts and parameters. Remember, there is a good chance that if you change something, you will incorrectly install it or break

something else in the process. Consider for a moment changing the processors board. First, you have to download all

parameters, remove a dozen connectors, replace the board, reload and reconnect, and if you make one mistake or bend one

tiny pin it WONT WORK. You always need to consider the risk of accidentally damaging the machine anytime you work on

it. It is cheap insurance to double-check a suspect part before physically changing it. The less work you do on the machine

the better.

96-8100 1-15-96

HAAS AUTOMATION, INC.

TROUBLESHOOTING

SERVICE

MANUAL

VF-SERIES

1. GENERAL MACHINE OPERATION

1.1 MACHINE NOT RUNNING

´Machine cannot be powered on.

l Checkinputvoltagetomachine(see"ElectricalService").

l Checkmaincircuitbreakerattoprightofelectricalcabinet;switchmustbeattheonposition.

l Checkovervoltagefuses(see"ElectricalService").

l CheckwiringtoPOWEROFFbuttononfrontcontrolpanel.

l CheckwiringtoAUTOOFFrelaytoIOPCB.

l ReplaceIOPCB(see"ElectricalService").

l ReplacePOWERPCB(see"ElectricalService").

´Machine can be powered on, but turns off by itself.

l Checksettings#1and#2forAutoOffTimerorOffatM30.

l CheckalarmhistoryforOVERVOLTAGEorOVERHEATshutdown.

l CheckACpowersupplylinesforintermittentsupply.

l CheckwiringtoPOWEROFFbuttononfrontcontrolpanel.

l ReplaceIOPCB(see"ElectricalService").

l CheckParameter57forPowerOffatE-STOP.

l ReplaceMOTIFPCB(see"ElectricalService").

´Machine turns on, keyboard beeps, but no CRT display.

l CheckforgreenPOWERLEDatfrontofCRT.

l CheckforpowerconnectionstoCRTfromIOPCB.

l Checkvideocable(760)fromVIDEOPCBtoCRT.

l ReplaceCRT(see"ElectricalService").

´Any LED on Microprocessor PCB goes out (except HALT).

l ReplaceMicroprocessorPCB(Section4.1,ElectricalService).

l ReplaceVIDEOPCB(see"ElectricalService").

l ReplaceMOTIFPCB(see"ElectricalService").

´Machine turns on, CRT works, but no keyboard keys work.

l Checkkeyboardcable(700)fromVIDEOtoKBIFPCB.

l Replacekeypad(see"ElectricalService").

lReplaceKBIFPCB(see"ElectricalService").

1-15-96 96-8100 3

TABLE OF CONTENTS

HAAS AUTOMATION, INC.

TROUBLESHOOTING

SERVICE

MANUAL

VF-SERIES

1.2 VIBRATION

Vibrationisasubjectiveevaluationwithperceptionsvaryingamongindividuals,makingitdifficulttodetermineinmild

casesifthereisanactualproblem. BecausetheVFSeriesusesagearhead,itwillbenoisierthanadirectdriveorbelt

system.Inobviouscases,itisamatterofdeterminingthesource_whichisnoteasy,sinceallpartsrotatetogetherand

soundcanbetransferredreadily.Vibrationsalsoneedtobedistinguishedfromnoisesuchasabadbearing.Wewillassume

thatvibrationswouldbesomethingthatcouldbefeltbyputtingyourhandonthespindlecovers. Onecrudemethodof

measurementwouldbetotakeanindicatoronamagneticbaseextended10inchesbetweenthetableandspindlehousing

andobservethereadingoftheindicator.Areadingofmorethan.001wouldindicateexcessivevibration.Thetwocommon

sourcesofnoisearethespindleandaxisdrives.Mostcomplaintsaboutvibration,accuracy,andfinishcanbeattributedto

incorrectmachiningpracticessuchaspoorqualityordamagedtooling,incorrectspeedsorfeeds,orpoorfixturing.Before

concludingthatthemachineisnotworking properly,ensurethatgoodmachiningpracticesarebeingobserved.These

symptomswillnotoccurindividually(Ex.Amachinewithbacklashmayvibrateheavily,yieldingabadfinish.).Putallofthe

symptomstogethertoarriveatanaccuratepictureoftheproblem.

´Machine vibrates while jogging the axis with the hand wheel.

lTheHAAScontrolusesveryhighgainaccelerationscurves.Thisvibrationasyoujogissimplytheservosquicklytrying

tofollowthehandledivisions.Ifthisisaproblem,tryusingasmallerdivisiononthehandle.Youwillnoticethevibration

moreatindividualclicksthanwhenyouareturningthehandlefaster.Thisisnormal.

´The machine vibrates excessively in a cut.

lThisisatoughonetocallbecausemachiningpracticescomeintoplay.Generallyspeaking,theleastrigidelementof

acutisthetoolbecauseitisthesmallestpart.Anycutterwillvibrateifpushedbeyonditstensilestrength.Inorderto

eliminatethemachineasthesourceoftheproblem,youneedtocheckthespindleandthebacklashoftheaxesasdescribed

inthefollowingsections.Oncemachiningpracticeshavebeeneliminatedasthesourceofvibration,observethemachinein

bothoperationandcuttingair.Movetheaxes(individually)withoutthespindleturningandthenturnthespindlewithout

movingtheaxes.Isolatewhetherthevibrationcomesfromthespindleheadorfromanaxis.Isolatethesourceofvibration

per"Spindle","ServoMotors/Leadscrews",and"GearboxandSpindleMotor"sections.

96-8100 1-15-96

HAAS AUTOMATION, INC.

TROUBLESHOOTING

SERVICE

MANUAL

VF-SERIES

1.3 ACCURACY

Beforeyoucomplainofanaccuracyproblem,pleasemakesureyoufollowthesesimpledosanddonts.

l Donteveruseawigglertestindicatorforlineardimensions.Theymeasureinanarcandhavesine/cosineerrorsover

largerdistances.

l Dontusemagneticbasesasaccurateteststops.Thehighaccel/deceloftheaxiscancausethemtomove.

l Dontattachtestpointstothesheetmetalofthespindleheadortable.

l Dontcheckforthermalgrowthwithanindicatoronalongextensionmagneticbase.

l Doinsurethattestindicatorsandstopsareabsolutelyrigidandmountedtomachinedcastingsurfaces.

l Docheckasuspectederrorwithanotherindicatorormethodforverification.

l Doensurethattheindicatorisparalleltotheaxisbeingcheckedtoavoidtangentialreadingerrors.

l Docenterdrillholesbeforeusingjobberlengthdrillsifaccuracyisquestioned.

lOncemachiningpracticeshavebeeneliminatedasthesourceoftheproblem,determinespecificallywhatthemachine

isdoingwrong.

´Machine will not interpolate a round hole.