Miller Electric Big Blue 251D Power Required To Start Motor, How Much Power Can Generator Supply?

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11-8. Power Required To Start Motor

4
4			AC MOTOR			2
1			AC MOTOR
		VOLTS	230	AMPS	2.5
		VOLTS	230	AMPS	2.5
3		CODE	M	Hz	60
		HP	1/4	PHASE 1

Single-Phase Induction Motor Starting Requirements

Motor Start	G		H	J	K	L	M		N		P
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

11-9. 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-480 Page 40

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Contents Processes DescriptionVisit our website at OM-480128 576AC January Engine Driven Welding GeneratorFrom Miller to You Table of Contents Options and Accessories Warranty Symbol Usage Arc Welding HazardsEngine Hazards Compressed Air Hazards Principal Safety Standards California Proposition 65 WarningsEMF Information Radiation can cause interferenceSignification des symboles − Consignes DE Sécurité − Lire Avant UtilisationUN Choc Électrique peut tuer LES Fumées ET LES GAZ peuvent être dangereuxLE Soudage peut provoquer un in- cendie ou une explosion DES Particules Volantes peuvent blesser les yeuxDES Pièces Chaudes peuvent provoquer des brûlures graves LE Bruit peut affecter l’ouïe’EXPLOSION DE LA Batterie peut DES Organes Mobiles peuvent provoquer des blessuresLA Chaleur DU Moteur peut pro- voquer un incendie ’AIR Comprimé peut provoquer des blessuresPrincipales normes de sécurité Information sur les champs électromagnétiquesSymbols And Definitions − DefinitionsDimensions, Weights, And Operating Angles − SpecificationsWeld, Power, And Engine Specifications Curve shows typical fuel use under weld or power loads Exceeding duty cycle can damage unit and void warrantyFuel Consumption Duty Cycle And OverheatingAC Generator Power Volt-Ampere CurvesOptional AC Power Plant Curves Connecting The Battery − InstallationInstalling Welding Generator Installing Muffler Pipe Engine Prestart ChecksStop engine and let cool Fuel Do not use gasoline. GasolineInstalling Ether Cylinder Optional Ether Starting Aid Connecting To Weld Output TerminalsSelecting Weld Cable Sizes 150 ft 200 ft 250 ft350 ft 400 ft 45 m 60 m 70 m 90 m 105 m 120 m Put terminals− Operating the Welding Generator Controls See SectionDescription Of Front Panel Controls See Section Remote A/V ControlStop engine and fix trouble if either light goes on Do not use Ether if engine is runningX 15 a + 120 V x 10 a = 3.0 kVA/kW OM-480 − Operating Auxiliary EquipmentVolt Duplex And Optional Gfci Receptacles Volt Duplex Receptacle Optional 240 V 15 a AC Receptacle RC1Circuit Breakers CB1 And CB2 X 10 a + 120 V x 5 a = 3.0 kVA/kWConnecting Optional AC Power Plant 240 Volt Twistlock Receptacle Optional − Maintenance and Troubleshooting Maintenance Label Servicing Air Cleaner Servicing Fuel And Lubrication Systems To change oil and filterTo replace primary fuel filter To replace secondary fuel filterModels With Automatic Idle Optional Adjusting Engine SpeedStandard Models Overload Protection Servicing Optional Ether Starting Aid Full EmptyInspecting And Cleaning Optional Spark Arrestor TroubleshootingStop engine and let cool. Reinstall cleanout plug WeldingGenerator Power Check connections to ac power plant see SectionEngine Maximum see Section− Electrical Diagram Circuit Diagram For Welding GeneratorWelding Generator − RUN-IN ProcedureWetstacking Run-In Procedure Using Load Bank Procedure at less thanStop engine Do not touch hot exhaust From flammables Do not PerformRun-In Procedure Using Resistance Grid Bank/gridFrom flammables Do not perform run-inGrounding Generator To Truck Or Trailer Frame − Generator Power GuidelinesSelecting Equipment 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 x 1000 = Starting AmperageTypical Connections To Supply Standby Power Work like a ProSelecting Extension Cord Use Shortest Cord Possible Current Load Watts AmperesOM-480 − Parts List 125 124 123 122120 121 117 1162526 126 Dia Part Description Quantity Mkgs 128 Panel, Front w/Components -1Item 111Panel, Front w/Components -1Item 111 Cont’d Generator Generator -1Item 114 IncludesPage Page Support ServiceYour distributor also gives To locate a Distributor or Service Agency visit Miller Electric Mfg. CoFor assistance in filing or settling claims, contact Your distributor and/or equipment manufacturer’s