Miller Electric ST 44 Series owner manual Troubleshooting

Page 16

5-2. Troubleshooting

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Problem

 

Solution

 

 

 

Unit is completely inoperative.

 

Check continuity of Power switch S1, and replace if necessary.

 

 

 

 

 

 

 

 

 

Reset circuit breaker CB1 if open.

 

 

 

 

 

 

 

 

 

Check input power source. See welding power source Technical Manual.

 

 

 

Wire does not feed, unit completely inop-

 

Turn Power switch On.

erative.

 

 

 

Check 14−pin receptacle connections.

 

 

 

 

 

 

 

 

 

 

 

 

 

Check input power or the CB

 

 

 

Wire does not feed.

 

Check gun trigger connection at wire feeder. Check gun trigger leads and trigger switch. See gun Owner’s

 

 

 

 

Manual.

 

 

 

 

 

 

 

 

 

Have Factory Authorized Service Agent check drive motor and control board PC1.

 

 

 

Wire feeds erratically.

 

Readjust hub tension and drive roll pressure.

 

 

 

 

 

 

 

 

 

Use correct size drive roll (see Parts List).

 

 

 

 

 

 

 

 

 

Clean or replace dirty or worn drive roll.

 

 

 

 

 

 

 

 

 

Remove weld spatter around nozzle opening.

 

 

 

 

 

 

 

 

 

Replace contact tip or liner. See gun Owner’s Manual.

 

 

 

 

 

 

 

 

 

Have Factory Authorized Service Agent check drive motor and control board PC1.

 

 

 

Wire feeds when Jog switch is pressed

 

Check gun trigger connection at wire feeder. Check gun trigger leads and trigger switch. See gun Owner’s

but not when gun trigger is pressed.

 

Manual.

 

 

 

Wire does not feed with Jog button S2B

 

Check continuity of Jog button S3, and replace if necessary.

pressed.

 

 

 

Check motor control board PC1 and connections, and replace if necessary

 

 

 

 

 

 

 

Electrode wire feeding stops or feeds

 

Realign drive rolls.

erratically during welding.

 

 

 

Check hub assembly (see Parts List).

 

 

 

 

 

 

 

Wire feeds as soon as power is applied.

 

Check gun trigger. See gun Owner’s Manual.

 

 

 

Wire does not feed until trigger is

 

Check for short between gun trigger leads and weld cable. Repair or replace gun trigger leads.

pressed but continues to feed after trig-

 

 

ger is released.

 

 

 

 

 

Gas valve rattles loudly and wire feeds

 

Check for short between gun trigger leads and weld cable. Repair or replace gun trigger leads.

slowly or erratically.

 

 

 

 

 

Gas does not flow; wire feeds.

 

Check gas valve and flowmeter.

 

 

 

Wire feeds, but gas does not flow with

 

Check coil voltage and connections of gas valve GS1. Check continuity of coil. Replace GS1 if necessary.

gun trigger pressed.

 

 

 

Check continuity of Purge switch S2A, and replace if necessary.

 

 

 

 

 

 

 

Wire feeds, but gas does not flow with

 

Check continuity of Purge switch S2A, and replace if necessary.

Purge switch S2 pressed.

 

 

 

Check coil voltage and connections of gas valve GS1. Check continuity of coil. Replace GS1 if necessary.

 

 

 

 

 

 

 

Wire feeds and electrode wire is ener-

 

Check coil voltage and connections of gas valve GS1. Check continuity of coil. Replace GS1 if necessary.

gized, but gas flow is irregular.

 

 

 

Clear blockage in gas hose or replace hose.

 

 

 

 

 

 

 

 

 

 

 

 

 

Clear blockage in gun. See gun Owner’s Manual.

 

 

 

Motor runs at full speed.

 

Check motor control board PC1 and connections, and replace if necessary.

 

 

 

 

 

 

 

 

 

Check resistance and connections of active wire speed potentiometers and replace if necessary.

 

 

 

Wire drive motor coasts (no brake at trig-

 

Check motor control board PC1 and connections, and replace if necessary.

ger release).

 

 

 

 

 

Meter does not work properly.

 

Check optional meter board PC2 and connections, and replace if necessary

 

 

 

 

 

OM-216 655 Page 12

Image 16
Contents Processes OM-216 655E 2007−03Description From Miller to You Table of Contents Standards DirectivesDecstatMilan6/05 Symbol Usage Marks a special safety messageArc Welding Hazards Electric Shock can killARC Rays can burn eyes and skin Welding can cause fire or explosionFlying Metal can injure eyes Buildup of GAS can injure or killCalifornia Proposition 65 Warnings EMF Information Principal Safety StandardsAbout Pacemakers + + − DefinitionsRating Label Symbols and DefinitionsMade In the EEC2003 − Installation Equipment Connection DiagramsSpecifications Gun Recommendation TableInstalling Wire Guide And Drive Roll Connecting Welding Gun And Weld CableAligning Wire Guide And Drive Rolls ST 44 Series Panel Controls − OperationST Blu Fab Panel Controls Use control to set wire feed speed before arc initiation Run-In Control and Burnback ControlRun-In Control Burnback ControlRoutine Maintenance − Maintenance & TroubleshootingMonths Troubleshooting − Electrical Diagram − Parts List ST 44 Complete Assembly Optional Equipment Shown−1. ST 44 Complete Assembly Roll Wire Drive Assembly All Models ST Blu Fab Wire Feed Assembly 000083432 656005029 Insulator, drive assembly 206219 1.2 mm Drive Roll And Wire Guide Kits 4 Drive RollCogged Page Page Effective January 1 For assistance in filing or settling claims, contact Your distributor and/or equipment manufacturer’sTransportation Department ITW Welding Products Italy S.r.l. Via Privata Iseo, 6/E