Miller Electric D-74D Troubleshooting, Disconnect power before troubleshooting, Trouble Remedy

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7-3. Troubleshooting

	Y Disconnect power before troubleshooting
Trouble	Remedy
Wire feeds, shielding gas flows, but	Check cable connections. Check cables for continuity, and repair or replace cables if necessary
electrode wire is not energized.	(see Section 5-3).
Wire feeder is on, display does not light	Check and reset circuit breaker at welding power source.
up, motor does not run, gas valve and
welding power source contactor do not
pull in.
Electrode wire feeding stops or feeds	Check gun trigger connection. See gun Owner’s Manual.
erratically during welding.	Check gun trigger. See gun Owner’s Manual.
	Check gun trigger. See gun Owner’s Manual.
	Readjust hub tension and drive roll pressure (see Section 5-7).
	Change to correct size drive roll (see 5-7).
	Clean or replace dirty or worn drive roll.
	Incorrect size or worn wire guides.
	Replace contact tip or liner. See gun Owner’s Manual.
	Remove weld spatter or foreign matter from around nozzle opening.
	Have Factory Authorized Service Agency check drive motor or motor control board PC1.
Wire birdnests between feeder and	Gun liner has to large of diameter opening, is clogged, or the end of the gun is not close enough
gun.	to the front set of drive rolls.
Motor runs slowly.	Check for correct input voltage.
Wire feeder power is on, displays light	Check welding gun trigger leads for continuity, and repair leads or replace gun.
up, but unit is inoperative.

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Contents Description OM-1500-6 206 805HProcesses File MIG GmawFrom Miller to You Table of Contents Standards Decwire6/05Directives Arc Welding Hazards Symbol UsageMarks a special safety message Electric Shock can killFlying Metal can injure eyes ARC Rays can burn eyes and skinWelding can cause fire or explosion Buildup of GAS can injure or killCalifornia Proposition 65 Warnings About Pacemakers Principal Safety StandardsEMF Information Indique un message de sécurité particulier UNE Décharge Électrique peut entraîner la mortLES Fumées ET LES GAZ peuvent être dangereux DES Particules Volantes peuvent blesser les yeux LE Soudage peut provoquer unIncendie ou une explosion DES Pièces Chaudes peuvent provoquer des brûlures graves’EMPLOI Excessif peut SUR Risque D’INCENDIE OU D’EXPLOLA Chute DE L’APPAREIL peut blesser DES Organes Mobiles peuvent provoquer des blessuresPrincipales normes de sécurité En ce qui concerne les stimulateurs cardiaquesKeep your head out of the fumes Disconnect input plug or power before working on machineDrive rolls can injure fingers Symbols And Definitions Rating Label For CE ProductsRating SpecificationsSite Selection Equipment Connection Diagrams Rear Panel Connections And Rotating Drive Assembly Pin Plug Information Wire Type, Size, And Feed Speed Capability TableMotor Speed Wire Type Wire Size Feed Speed Capability Gun Recommendation TableInstalling And Threading Welding Wire Right Side Motor Control Board PC1 Left Side Motor PC101 Setting Internal DIP SwitchesCurrent Detect Override OFF Factory Default S1-1 And S1-2 Automatic Run-In OFF S1-1 And S1-2Optional Equipment DIP Switch Settings PC60Power Switch Power SwitchLeft/Right Select Switch Jog/PurgeVoltage Control And Digital Meters Trigger Hold SwitchTrigger Hold Switches Months Routine MaintenanceDisconnect power before maintaining Diagnostics Wire feeds, shielding gas flows, but TroubleshootingDisconnect power before troubleshooting Trouble RemedyOM-1500-6 − Electrical Diagram 204 716-B Main Assembly 21 −2Part Description Quantity Control Box Harness Connectors/Receptacles 130Drive Assembly, Wire Drive Assembly, Wire -1Item203 Roll Drive Drive Roll And Wire Guide Kits Fraction MetricKit Roll Wire Size Roll Drive KitPage Page Support ServiceYour distributor also gives For assistance in filing or settling claims, contact To locate a Distributor or Service Agency visitMiller Electric Mfg. Co Your distributor and/or equipment manufacturer’s