Miller Electric 251 NT manual Table of Contents

Page 3

WARNING

This product, when used for welding or cutting, produces fumes or gases which contain chemicals known to the State of California to cause birth defects and, in some cases, cancer. (California Health & Safety Code Section 25249.5 et seq.)

WARNING

Battery posts, terminals and related accessories contain lead and lead compounds, chemicals known to the State of California to cause cancer and birth defects or other reproductive harm. Wash hands after handling.

WARNING

The engine exhaust from this product contains chemicals known to the State of California to cause cancer, birth defects, or other reproductive harm.

The following terms are used interchangeably throughout this manual: MIG = GMAW, Wire Welding

TIG = GTAW

Stick = SMAW

TABLE OF CONTENTS

SECTION 1 – SAFETY PRECAUTIONS - READ BEFORE USING

1

1-1.

Symbol Usage

1

1-2.

Arc Welding Hazards

1

1-3.

Engine Hazards

2

1-4. Additional Symbols For Installation, Operation, And Maintenance

3

1-5.

Principal Safety Standards

4

1-6.

EMF Information

4

SECTION 1 – CONSIGNES DE SÉCURITÉ – LIRE AVANT UTILISATION

5

1-1.

Signification des symboles

5

1-2.

Dangers relatifs au soudage à l’arc

5

1-3.

Dangers existant en relation avec le moteur

6

1-4. Dangers supplémentaires en relation avec l’installation, le fonctionnement

 

 

et la maintenance

7

1-5.

Principales normes de sécurité

8

1-6.

Information sur les champs électromagnétiques

8

SECTION 2 – DEFINITIONS

9

2-1.

Symbol Definitions

9

SECTION 3 – SPECIFICATIONS

9

3-1. Weld, Power, And Engine Specifications

9

3-2. Dimensions, Weights, and Operating Angles

10

3-3.

Fuel Consumption

10

3-4.

Auxiliary Power Curve

11

3-5.

Duty Cycle

11

3-6.

Volt-Ampere Curves

12

SECTION 4 – INSTALLATION

13

4-1.

Installing Welding Generator

13

4-2.

Engine Prestart Checks

13

4-3. Activating The Dry Charge Battery (If Applicable)

14

4-4.

Connecting The Battery

15

4-5.

Installing Exhaust Pipe

15

4-6. Connecting To Weld Output Terminals

15

4-7. Selecting Weld Cable Sizes

16

4-8. Remote 14 Receptacle Information

16

4-9. Adjusting MIG Weld Puddle Consistency

17

SECTION 5 – OPERATING WELDING GENERATOR

18

5-1.

Front Panel Controls

18

5-2.

Remote Amperage/Voltage Control

19

SECTION 6 – OPERATING AUXILIARY EQUIPMENT

20

6-1. Auxiliary Power Receptacles And Circuit Breakers

20

6-2. Optional Auxiliary Power Receptacles

21

SECTION 7 – MAINTENANCE AND TROUBLESHOOTING

22

7-1.

Routine Maintenance

22

7-2.

Maintenance Label

23

7-3.

Servicing Air Cleaner

24

7-4. Servicing Optional Spark Arrestor

24

7-5. Changing Engine Oil, Oil Filter, And Fuel Filter

25

7-6.

Adjusting Engine Speed

26

7-7.

Overload Protection

27

7-8.

Troubleshooting

27

SECTION 8 – ELECTRICAL DIAGRAM

30

SECTION 9 – AUXILIARY POWER GUIDELINES

32

SECTION 10 – PARTS LIST

40

OPTIONS AND ACCESSORIES

 

WARRANTY

 

Page 2 Page 4
Image 3
Page 2 Page 4
Contents OM-486 ProcessesDescription From Miller to You Table of Contents Page ARC Rays can burn eyes and skin Symbol UsageArc Welding Hazards Electric Shock can killEngine Hazards Engine Heat can cause fire Battery Explosion can BlindMoving Parts can cause injury Engine Exhaust Gases can killARC Welding can cause interference Principal Safety StandardsEMF Information Radiation can cause interferenceLES Fumé ES ET LES GAZ peuvent ê tre dangereux Signification des symbolesConsignes DE SÉ Curité Lire Avant Utilisation UN Choc É Lectrique peut tuerLE Bruit peut affecter l’ouïe LE Soudage peut provoquer un in- cendie ou une explosionDES Particules Volantes peuvent blesser les yeux DES PIÈ CES Chaudes peuvent provoquer des brû lures gravesLA Chute DE L’APPAREIL peut blesser DES Organes Mobiles peuvent provoquer des blessures’EXPLOSION DE LA Batterie peut LA Chaleur DU Moteur peut pro- voquer un incendieConsignes relatives aux stimulateurs cardiaques Principales normes de sé curitéInformation sur les champs é lectromagné tiques LE Soudage À L’ARC risque de provoquer des interfé rencesDefinitions SpecificationsSymbol Definitions Weld, Power, And Engine SpecificationsDimensions, Weights, and Operating Angles DimensionsFuel Consumption Auxiliary Power Curve Exceeding duty cycle can damage unit and void warrantyDuty Cycle Volt-Ampere Curves CC/DC ModeCV/DC Mode CC/AC ModeInstallation Installing Welding GeneratorEngine Prestart Checks Charger Activating The Dry Charge Battery If ApplicableDo not overfill battery cells Read and follow all instrucConnect negative cable last Connecting The BatteryInstalling Exhaust Pipe Connecting To Weld Output Terminals10 100% Duty Cycle Selecting Weld Cable SizesRemote 14 Receptacle Information 100 ft 30 m Or LessTo stiffen weld puddle Adjusting MIG Weld Puddle ConsistencyStop engine To wet out weld puddleOperating Welding Generator DC Polarity/AC SwitchDo not switch under load Remote Amperage/Voltage SwitchRemote Amperage/Voltage Control Auxiliary Power Receptacles And Circuit Breakers Operating Auxiliary EquipmentWeld Current 120 240 Gfci Receptacle Option Optional Auxiliary Power ReceptaclesMaintenance and Troubleshooting Maintenance Label Servicing Air Cleaner Servicing Optional Spark ArrestorStop engine and let cool Changing Engine Oil, Oil Filter, And Fuel Filter Adjusting Engine Speed Idle Speed AdjustmentWeld/Power Speed Adjustment Trouble Remedy TroubleshootingOverload Protection WeldingSee engine manual Low weld output Check control settingsCheck and clean air cleaner as necessary see Section Check and adjust engine speed see SectionCheck governor according to engine manual Auxiliary PowerCheck receptacle wiring and connections EngineCircuit Diagram For Welding Generator Electrical DiagramST-190 578-B Auxiliary Power Guidelines Selecting EquipmentGrounding Generator To Truck Or Trailer Frame Amperes x Volts = Watts Grounding When Supplying Building SystemsHow Much Power Does Equipment Require? Earth ground if supplyingFarm/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 WattsContractor Rating Starting Watts Running Watts Approximate Power Requirements For Contractor EquipmentKVA/HP x HP x Power Required To Start MotorHow Much Power Can Generator Supply? Single-Phase Induction Motor Starting Requirements240 120 Ground Typical Connections To Supply Standby PowerCurrent Load Watts Amperes Selecting Extension Cord Use Shortest Cord PossibleParts List Main Assembly24-Fig Dia Part Description Mkgs Quantity Panel, Front w/Components Panel, Front w/Components -1 Item Generator -1 Item Page Page Page Service Your distributor also givesSupport Miller Electric Mfg. Co Owner’s Record

251 NT specifications

The Miller Electric 251 NT is a highly regarded multi-process welding machine known for its versatility and advanced features, making it an ideal choice for professionals in various industries. With its robust construction and user-friendly interface, the 251 NT provides an efficient solution for MIG, TIG, and Stick welding applications.

One of the main features of the Miller Electric 251 NT is its impressive output range, which allows for welding on a variety of materials and thicknesses. It delivers up to 250 amps of power, enabling users to tackle both thin and thick metals with ease. Additionally, the machine is equipped with an Auto-Set feature, which automatically adjusts the welding settings according to the material thickness and type. This eliminates the guesswork, significantly enhancing productivity and reducing setup time.

Another noteworthy aspect of the Miller Electric 251 NT is its inverter technology. This advanced technology provides a compact, lightweight design without compromising performance. Inverter technology allows for greater energy efficiency, resulting in reduced operational costs over time. The 251 NT also features a Duty Cycle of 60% at 250 amps, which means it can handle demanding tasks while maintaining optimal performance.

The Miller Electric 251 NT is designed with user convenience in mind. The intuitive digital display offers clear visibility of the settings, allowing welders to make quick adjustments. Furthermore, the machine includes a built-in memory function to store frequently used parameters, enhancing workflow efficiency.

Safety is a key component of the 251 NT's design. It comes equipped with various safety features, including overload protection and a thermal overload warning system. These features ensure that the machine operates within safe limits, minimizing the risk of damage and ensuring longevity.

In terms of portability, the Miller Electric 251 NT's lightweight design and integrated handle make it easy to transport between job sites. The durable housing protects the internal components, making it suitable for rigorous use in demanding environments.

Overall, the Miller Electric 251 NT offers a combination of power, flexibility, and ease of use, making it a top choice for welders looking to enhance their capabilities across multiple welding processes. Whether in a professional shop or on a construction site, the 251 NT stands out as a reliable and efficient welding solution.
Top Page Image Contents