Weld Test, Troubleshooting − Porosity | Miller Electric 250 specification

15-13. Weld Test

2 To 3 in

(51-76 mm)

1/4 in (6.4 mm)

3
	3
	2 To 3 in
	(51-76 mm)
2	2
2
1	1

1Vise

2Weld Joint

3Hammer

Strike weld joint in direction shown. A good weld bends over but does not break.

S-0057-B

15-14. Troubleshooting − Porosity

Porosity − small cavities or holes resulting from gas pockets in weld metal.

Possible Causes	Corrective Actions

Arc length too long.	Reduce arc length.

Damp electrode.	Use dry electrode.

Workpiece dirty.	Remove all grease, oil, moisture, rust, paint, coatings, slag, and dirt from work surface before
	welding.

15-15. Troubleshooting − Excessive Spatter

Excessive Spatter − scattering of molten metal particles that cool to solid form near weld bead.

Possible Causes	Corrective Actions

Amperage too high for electrode.	Decrease amperage or select larger electrode.

Arc length too long or voltage too high.	Reduce arc length or voltage.

OM-217 455 Page 63

Page 67

Image 67

Miller Electric 250 manual Weld Test, Troubleshooting − Porosity, Troubleshooting − Excessive Spatter

Contents

2007−05−21 OM-217 455HFile Engine Drive Visit our website at From Miller to You Table of Contents 13-5 13-213-3 13-4 HOT Parts can cause severe burns Symbol UsageArc Welding Hazards Electric Shock can kill Welding can cause fire or explosion Fumes and Gases can be hazardousBuildup of GAS can injure or kill ARC Rays can burn eyes and skin Compressed Air Hazards Engine Hazards Falling Unit can cause injury Welding Wire can cause injuryHOT Parts can cause burns and injury Fire or Explosion hazard Radiation can cause interference Principal Safety StandardsCalifornia Proposition 65 Warnings EMF Information Indique des instructions spécifiques Signification des symboles− Consignes DE Sécurité − Lire Avant Utilisation UN Choc Électrique peut tuer LES Fumées ET LES GAZ peuvent être dangereux DES Pièces Chaudes peuvent provoquer des brûlures gravesLE Soudage peut provoquer un in cendie ou une explosion ’EXPLOSION DE LA Batterie peu LE Bruit peut affecter l’ouïeDES Organes Mobiles peuvent pro voquer des blessures ’AIR Comprimé peut provoquer des blessures LA Chaleur DU Moteur peut pro- voquer un incendieRisque D’INCENDIE OU D’EXPLO- Sion ’EMPLOI Excessif peut LE Surchauffement peut endom- mager le moteur électriqueDES Organes Mobiles peuvent provoquer des blessures LES Fils DE Soudage peuvent provoquer des blessures En ce qui concerne les implants médicaux Proposition californienne 65 AvertissementsPrincipales normes de sécurité Information EMF − Definitions − SpecificationsSymbol Definitions Weld, Power, and Engine Specifications Dimensions For Units With Optional Running Gear Dimensions, Weights, and Operating AnglesDimensions Mounting − InstallationInstalling Welding Generator Vehicle frame. Always connect a ground wire Stop engine and let cool Installing Exhaust PipeConnecting the Battery + − Overview And Engine Prestart Checks Daily pre-start checks Engine Left Side Engine Right SideStarting engine for the first time Run-in period first 100 hours Tools Needed Do not place Connecting to Weld Output TerminalsCorrect Installation Work Weld Output Terminal Selecting Weld Cable Sizes Do not use glow plugs longer than 20 seconds Engine Control SwitchesPlace switch in Run position to operate most MIG equipment − Operating the Welding Generator Weld Output Controls Work Clamp Electrode Holder Typical Stick Welding Connections And Control SettingsTypical Settings For 7018 1/8 Electrode Stop engine Set Weld Process Selector switch to Wire − position Dcen Typical MIG Welding Connections And SettingsSet Weld Process Selector switch to Wire + Dcep position Set Weld Process Selector switch to Wire + position Tools Needed 3/4 Work Not Used To Work Left Side View To verify Gfci is working properly Generator Power Receptacles− Operating Auxiliary Equipment At least once a month, run engine at Simultaneous Weld And Power Battery Charge Controls − Operating Optional Battery ChargerDetermining Battery Charging Current Battery Charge Cable Connections Minutes Battery Charging Procedure Start Your Professional Welding Career Now Routine Maintenance − Maintenance and Troubleshooting Stop engine and let cool Oil And Fuel Maintenance Label And Engine Maintenance Activities 804 197-A / Ref 803 111-A / 227 Damage when determining whether Cleaner or with dirty element. EngineMent is not covered by the warranty Air cleaner primary element can Checking Fuel Solenoid Adjusting Engine SpeedAdjusting Fuel Solenoid Position Stop screw is factory-set and should not be adjusted Check for non-binding Adjusting Throttle SolenoidChecking Throttle Solenoid 16 mm Adjusting Idle Speed Making Engine Speed AdjustmentsAdjusting Weld/Power Speed Supplementary Protector CB8 Overload ProtectionComponent Panel Stop engine Fuse F1 Trouble Remedy Troubleshooting TablesGenerator Power Welding Engine Maintenance Display Action Current transformer CT1, and throttle solenoid TS1 − Parts ListRecommended Spare Parts Recommended Spare Parts Circuit Diagram For Welding Generator − Electrical Diagrams 228 719-B OM-217 455 231 607-B Run-In And Wetstacking − RUN-IN and Wetstacking Idle − Performance DataFuel Consumption Curves US Gal./Hr AC Amperes At 120 Volts Generator Power CurveDuty Cycle Volts DC Amps CC/AC Stick Mode AC Volts Stick Mode Volt-Ampere CurvesAC Amps DC Amps MIG Mode Volt-Ampere Curve Selecting Equipment − Generator Power GuidelinesGrounding Generator To Truck Or Trailer Frame Amperes x Volts = Watts Grounding When Supplying Building SystemsHow Much Power Does Equipment Require? Use ground device as stated in electrical codes Farm/Home Equipment Rating Starting Watts Running Watts Approximate Power Requirements For Industrial MotorsApproximate Power Requirements For Farm/Home Equipment Industrial Motors Rating Starting Watts Running Watts Contractor Rating Starting Watts Running Watts Approximate Power Requirements For Contractor Equipment KVA/HP x HP x 1000 / Volts = Starting Amperage Power Required To Start MotorHow Much Power Can Generator Supply? Single-Phase Induction Motor Starting Requirements Typical Connections To Supply Standby Power Selecting Extension Cord Use Shortest Cord Possible Weld current starts when electrode touches work- piece Stick Welding Procedure− Stick Welding Smaw Guidelines Striking an Arc − Scratch Start Technique Electrode and Amperage Selection ChartStriking an Arc − Tapping Technique 10-30 9090 End View of Work Angle Poor Weld Bead CharacteristicsGood Weld Bead Characteristics Positioning Electrode Holder Electrode Movement During Welding Conditions That Affect Weld Bead Shape 16 in 30 1.6 mm Tack Welds Butt JointsLap Joint Tee Joint Possible Causes Corrective Actions Troubleshooting − PorosityTroubleshooting − Excessive Spatter Weld Test Troubleshooting − Lack Of Penetration Troubleshooting − Incomplete FusionTroubleshooting − Excessive Penetration Troubleshooting − Waviness Of Bead Troubleshooting − Burn-ThroughTroubleshooting − Distortion Work like a Pro Your distributor also gives ServiceSupport Your distributor and/or equipment manufacturer’s To locate a Distributor or Service Agency visitMiller Electric Mfg. Co For assistance in filing or settling claims, contact

Miller Electric 250 Weld Test, Troubleshooting − Porosity, Troubleshooting − Excessive Spatter

Models: 250

15-13. Weld Test

15-14. Troubleshooting − Porosity

Possible Causes

Corrective Actions

15-15. Troubleshooting − Excessive Spatter

OM-217 455 Page 63