Miller Electric 251 NT manual Power Required To Start Motor, How Much Power Can Generator Supply?

Page 40

9-8. Power Required To Start Motor

4

 

 

AC MOTOR

 

2

1

 

 

 

 

VOLTS

230

AMPS

2.5

 

 

 

 

 

3

 

CODE

M

Hz

60

 

 

 

HP

1/4

PHASE 1

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Single-Phase Induction Motor Starting Requirements

Motor Start

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Code

G

 

H

 

J

K

L

M

 

N

 

P

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

KVA/HP

6.3

 

7.1

8.0

9.0

10.0

11.2

 

12.5

 

14.0

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

kVA/HP x HP x 1000

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

= STARTING AMPERAGE

 

 

 

 

 

 

 

VOLTS

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

EXAMPLE: Calculate the starting amperage required for a 230 V, 1/4

 

 

HP motor with a motor start code of M.

 

 

 

 

 

 

 

Volts = 230

HP = 1/4 Using Table, Code M results in kVA/HP = 11.2

11.2 x 1/4 x 1000

= 12.2 A

Starting the motor requires 12.2 amperes.

 

230

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

1Motor Start Code

2Running Amperage

3Motor HP

4Motor Voltage

To find starting amperage:

Step 1: Find code and use table to find kVA/HP. If code is not listed, multiply running amperage by six to find starting amperage.

Step 2: Find Motor HP and Volts.

Step 3: Determine starting amper- age (see example).

Welding generator amperage out- put must be at least twice the motor’s running amperage.

S-0624

9-9. How Much Power Can Generator Supply?

1

2

1Limit Load To 90% Of Generator Output

Always start non-resistive (motor) loads in order from largest to small- est, and add resistive loads last.

2 5 Second Rule

If motor does not start within 5 seconds, turn off power to prevent motor damage. Motor requires more power than generator can supply.

Ref. ST-800 396-A / S-0625

OM-486 Page 36

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Contents Processes OM-486Description From Miller to You Table of Contents Page Symbol Usage Arc Welding HazardsElectric Shock can kill ARC Rays can burn eyes and skinEngine Hazards Battery Explosion can Blind Moving Parts can cause injuryEngine Exhaust Gases can kill Engine Heat can cause firePrincipal Safety Standards EMF InformationRadiation can cause interference ARC Welding can cause interferenceSignification des symboles Consignes DE SÉ Curité Lire Avant UtilisationUN Choc É Lectrique peut tuer LES Fumé ES ET LES GAZ peuvent ê tre dangereuxLE Soudage peut provoquer un in- cendie ou une explosion DES Particules Volantes peuvent blesser les yeuxDES PIÈ CES Chaudes peuvent provoquer des brû lures graves LE Bruit peut affecter l’ouïeDES Organes Mobiles peuvent provoquer des blessures ’EXPLOSION DE LA Batterie peutLA Chaleur DU Moteur peut pro- voquer un incendie LA Chute DE L’APPAREIL peut blesserPrincipales normes de sé curité Information sur les champs é lectromagné tiquesLE Soudage À L’ARC risque de provoquer des interfé rences Consignes relatives aux stimulateurs cardiaquesSpecifications Symbol DefinitionsWeld, Power, And Engine Specifications DefinitionsDimensions Dimensions, Weights, and Operating AnglesFuel Consumption Exceeding duty cycle can damage unit and void warranty Auxiliary Power CurveDuty Cycle CC/DC Mode CV/DC ModeCC/AC Mode Volt-Ampere CurvesInstalling Welding Generator InstallationEngine Prestart Checks Activating The Dry Charge Battery If Applicable Do not overfill battery cellsRead and follow all instruc ChargerConnecting The Battery Installing Exhaust PipeConnecting To Weld Output Terminals Connect negative cable lastSelecting Weld Cable Sizes Remote 14 Receptacle Information100 ft 30 m Or Less 10 100% Duty CycleAdjusting MIG Weld Puddle Consistency Stop engineTo wet out weld puddle To stiffen weld puddleDC Polarity/AC Switch Do not switch under loadRemote Amperage/Voltage Switch Operating Welding GeneratorRemote Amperage/Voltage Control Operating Auxiliary Equipment Auxiliary Power Receptacles And Circuit BreakersWeld Current 120 240 Optional Auxiliary Power Receptacles Gfci Receptacle OptionMaintenance and Troubleshooting Maintenance Label Servicing Optional Spark Arrestor Servicing Air CleanerStop engine and let cool Changing Engine Oil, Oil Filter, And Fuel Filter Idle Speed Adjustment Adjusting Engine SpeedWeld/Power Speed Adjustment Troubleshooting Overload ProtectionWelding Trouble RemedyLow weld output Check control settings Check and clean air cleaner as necessary see SectionCheck and adjust engine speed see Section See engine manualAuxiliary Power Check receptacle wiring and connectionsEngine Check governor according to engine manualElectrical Diagram Circuit Diagram For Welding GeneratorST-190 578-B Selecting Equipment Auxiliary Power GuidelinesGrounding Generator To Truck Or Trailer Frame Grounding When Supplying Building Systems How Much Power Does Equipment Require?Earth ground if supplying Amperes x Volts = WattsApproximate Power Requirements For Industrial Motors Approximate Power Requirements For Farm/Home EquipmentIndustrial Motors Rating Starting Watts Running Watts Farm/Home Equipment Rating Starting Watts Running WattsApproximate Power Requirements For Contractor Equipment Contractor Rating Starting Watts Running WattsPower Required To Start Motor How Much Power Can Generator Supply?Single-Phase Induction Motor Starting Requirements KVA/HP x HP xTypical Connections To Supply Standby Power 240 120 GroundSelecting Extension Cord Use Shortest Cord Possible Current Load Watts AmperesMain Assembly Parts List24-Fig Dia Part Description Mkgs Quantity Panel, Front w/Components Panel, Front w/Components -1 Item Generator -1 Item Page Page Page Your distributor also gives ServiceSupport Owner’s Record Miller Electric Mfg. Co

251 NT specifications

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