Amp Motor Circuit
Amp Motor Circuit
What size Circuit Breaker to use?
6 HP 60 Gallon Air Compressor
The sticker on the electric motor-
Volts- ~208-230
Amp– 15
AMB– 40
PH– 1
Code– J
How many amp circuit breaker do I use when I wire it? I have a 50 amp CB that I left with the air comp., is this the correct one?
10/2 w-ground, if it matters.
My advice is to use a minimum 20 amp breaker because of start up amps and load amps. The best way to calculate the size of the circuit is to put an amp gage on the compressor and watch how much amps it pulls from an empty tank to full. Then you will know how to size your circuit.
The 50 amp breaker you mentioned will most likely be too big and it won’t be able to protect your compressor from overload.
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Westinghouse Motor Circuit Protector HMCP050K2C Ser C 50Amp A 50A 600V 3Pole $59.65 |
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CUTLER HAMMER HMCPS007C0C NEW IN BOX MOTOR CIRCUIT 7 AMP 3 POLE 600 VAC 250 VDC $200.00 |
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SIEMENS JXD63H400 400 AMP MOTOR CIRCUIT INTERRUPTER ,USED $200.00 |
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Westinghouse Motor Circuit Protector HMCP015E0C 15Amp A 15A 3 Pole 600V Series C $13.50 |
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WESTINGHOUSE CIRCUIT BREAKER MCP331000C 100 AMP 600 V MOTOR CIRCUIT PROTECTOR $249.99 |
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Cutler Hammer HMCP007C0C 7 Amp Motor Circuit Protector $215.00 |
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Cutler Hammer HMCP003A0C 3 Amp Motor Circuit Protector $235.75 |
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series c motor circuit protector hmcp 3 pole 30amp $79.99 |
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GENERAL ELE, MAG-BREAK 100 AMP MOTOR CIRCUIT BREAKER! $150.00 |
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GE TJC36400B MAG-BREAK MOTOR CIRCUIT PROTECTOR 400 AMP $135.00 |
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SQUARE D FAL 36015 13M MOTOR CIRCUIT INTERRUPTER 600V 15A AMP 180TRIP FAL36015 $9.07 |
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WESTINGHOUSE MCP0322RC Motor Circuit Breaker 3 amp 3 pole 600 VAC $39.62 |
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Telemecanique GV3ME40 Starter Motor Circuit Breaker 25-40Amp IEC $124.87 |
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CUTLER-HAMMER MOTOR CIRCUIT PROTECTOR HMCP030HIC, 30 AMPS $45.00 |
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Cutler-Hammer MCP23480 Motor Circuit Protector, 50 Amp $190.00 |
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Cutler-Hammer MCP23480C Motor Circuit Protector, 50 Amp $190.00 |
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Cutler-Hammer MCP03150 Motor Circuit Protectors, 15 Amp $260.00 |
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Siemens Motor Protector, Circuit Breaker, 3VU1300-1NK00, 5-8 Amp $85.00 |
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Siemens Motor Protector, Circuit Breaker , 6-10 Amp, 3VU1300-1ML00 $85.00 |
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Siemens Motor Protector, Circuit Breaker, 2.4-4.0 Amp, 3VU1300-1MJ00 $85.00 |
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Siemens 3VH1330-1MF Motor Circuit Protector 0.6- 1AMP $59.50 |
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Siemens 3VU1300-1MF00 Motor Circuit Protector 0.6- 1AMP $75.00 |
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GC 3 AMP CIRCUIT BREAKER 50 VOLTS DC OR 250 AC AUTOMOTIVE SMALL MOTOR LIGHTS $3.99 |
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Westinghouse MOTOR CIRCUIT PROTECTOR 15A 15 AMP 3-POLE 3-PHASE 600V HMCP015E0C $30.00 |
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SQUARE D MAG-GARD MOTOR CIRCUIT PROTECTOR 3 AMP 480 V $59.00 |
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Mitsubishi MB30-CS 16 AMP 3 Pole Motor Circuit Breaker $49.99 |
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GENERAL ELECTRIC TEC36150 150 AMP MOTOR CIRCUIT PROTECTOR ,NIB $150.00 |
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Siemens Motor Circuit Interrupter ED6-EAT1 2AMP $14.99 |
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Westinghouse HMCP100R3C motor circuit protector 100 amp, 600VAC Guaranteed $285.00 |
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GE 100 amp breaker TEC36100 motor circuit protector, 100 amp, 600VAC Guaranteed $150.00 |
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GE Breaker TEC36003 motor circuit protector 3 amp 600VAC $150.00 |
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Cutler-Hammer 400 amp motor circuit protector $300.00 |
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Siemens 3Amp Motor Circuit Interrupters ED63A003 NR $59.99 |
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General Electric Mag-Break Motor Circuit Protector TEC36003 3Amps 3 Poles 600 AC $125.00 |
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Cutler-Hammer MCP13300 Motor Circuit Protector, 30 Amp $240.00 |
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NEW — SIEMENS 6 AMP MOTOR PROTECTION CIRCUIT BREAKER $10.00 |
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GE Mag Break Motor Circuit Breaker TEC36007, 7 amp, 3 pole $7.00 |
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T&H MARINE TROLLING MOTOR 50 AMP CIRCUIT BREAKER KIT $46.34 |
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7 AMP Motor Circuit Breaker Interrupter FREE SHIPPING $334.00 |
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100 AMP Motor Circuit Breaker Interrupter FREE SHIPPING $577.00 |
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HMCP E 3 Pole 3 Amp Motor Circuit Protector Cuttler Hammer HMCPE003A0C $35.00 |
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WESTINGHOUSE HMCP100R3 Motor Circuit Protector 100A 100 Amp A 3P 3 Pole 600V NEW $102.50 |
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NEW IN BOX, ITE EF3A100 MOTOR CIRCUIT INTERRUPTER CIRCUIT BREAKER 100 AMP 480V $700.00 |
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Standard Motor Products Circuit Breaker Lot of 3 15,20,30 Amp $12.95 |
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Allen Bradley A-B Motor Protection Circuit Breaker 80A Amp140M-I8E-C80 A 140M-I8 $350.00 |
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Cutler Hammer Motor Circuit Switch 30 Amp 5-25 HP 600v $200.00 |
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WestingHouse Motor Circuit Breaker 50 AMP $99.00 |
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General Electric TEC36007 Motor Circuit Protector 7 Amp, 600 VAC, 3 Pole Breaker $22.95 |
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Telemecanique GV2 (GV2ME22) Motor Circuit Breaker (GV2ME22 / 20-25Amp) Schneider $47.74 |
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Telemecanique GV2 (GV2ME20) Motor Circuit Breaker (GV2ME20 / 13-18Amp) Schneider $46.15 |
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Westinghouse Series C Motor Circuit Protector HMCP030H1 30 Amp $65.00 |
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Westinghouse 3 Amp 600 V 3-Pole Motor Circuit Protector Breaker HMCP003A0C $15.00 |
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WESTINGHOUSE 3AMP MOTOR CIRCUIT PROTECTOR $20.00 |
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Westinghouse HMCP 30 AMP Motor Circuit Protector $80.00 |
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Westinghouse HMCP 3 AMP Motor Circuit Protector $20.00 |
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Square D- 30amp Combination Motor Control Switch /Circuit breaker $219.95 |
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WESTINGHOUSE HMCP250W5W 250 AMP MOTOR CIRCUIT PROTECTOR ,USED w/ DAMAGE $75.00 |
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Telemecanique GV2 M02 Motor circuit breaker .16-.25 Amp $49.99 |
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Telemecanique GV2 M08 Motor circuit breaker 2.5-4 Amp $49.99 |
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20 Amp SELF-RESET BLOWER MOTOR CIRCUIT BREAKER $4.95 |
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20 AMP CIRCUIT BREAKER power door lock motor wiring kit $4.95 |
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Allen Bradley 1492-CB1G050 manual Motor Controller 5amp 5a Circuit Breaker NEW $37.50 |
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Allen Bradley 1492-CB1G040 manual Motor Controller 4amp 4a Circuit Breaker NEW $37.50 |
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Allen Bradley 1492-CB1G030 manual Motor Controller 3amp 3a Circuit Breaker NEW $37.50 |
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Allen Bradley 1492-CB1G020 manual Motor Controller 2amp 2a Circuit Breaker NEW $37.50 |
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Allen Bradley 1492-CB1G010 manual Motor Controller 1amp 1a Circuit Breaker NEW $37.50 |
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(1715-4) ITE Motor Circuit Interrupter, 50 amp, 3 pole $24.95 |
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ITE MOTOR CIRCUIT BREAKER INTERRUPTER 30 AMP E63A030 $21.99 |
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ITE MOTOR CIRCUIT BREAKER INTERRUPTER 25 AMP E63A025 $27.99 |
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Square D FHP3600712M Circuit Breaker Motor Protector, MCP, 7 Amp, 600 Volt $40.00 |
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CUTLER-HAMMER SERIES C MOTOR CIRCUIT PROTECTOR 3 AMP $10.00 |
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WESTINGHOUSE SERIES C MOTOR CIRCUIT PROTECTOR 3 AMP $10.00 |
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150 AMP GE 600 VOLT MOTOR CIRCUIT BREAKER CATALOG # SELA36A10150 $600.00 |
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TELEMECANIQUE GV1-M10 MOTOR CIRCUIT PROTECTOR 4 – 6 AMP $10.00 |
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NOS! GE 30A 30 AMP MOTOR CIRCUIT BREAKER TEC36030 $39.95 |
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Westinghouse Motor Circuit Protector #HMCP250A5 250 Amp 600 VAC 250 VDC 3 Pole $400.00 |
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Westinghouse MCP0358CR 7 Amp Motor Circuit Protector $19.99 |
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Telemecanique GV2 P16 Starter Motor Circuit Breaker 9-14 Amp 3 Pole BRAND NEW $139.99 |
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WESTINGHOUSE MOTOR CIRCUIT PROTECTOR MCP431550 150AMP $150.00 |
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WESTINGHOUSE MOTOR CIRCUIT PROTECTOR HMCP003AOC 3 AMP $25.00 |
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Westinghouse MCP 23480RC 50Amp 3pole Motor Circuit Breaker 600V lug in /out $45.00 |
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Westinghouse MCP 03150CR 15Amp 3pole Motor Circuit Breaker 600V lug in /out $25.00 |
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CUTLER-HAMMER HMCP030H1C 30 AMP MOTOR CIRCUIT PROTECTOR, USED $29.00 |
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Cutler Hammer HMCP070M2C Motor Circuit Protector 70 Amp 3 Pole100% POSITIVE F.B. $299.99 |
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Merlin Gerin CK1200H Circuit Breaker with 1000 amp rating plug Motor Operator $5,550.00 |
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Westinghouse HMCP003A0C 3 Amp 3P Motor Circuit Breaker $149.99 |
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ALLEN BRADLEY 140M-C2E-B16 MOTOR PROTECTION CIRCUIT BREAKER 3 POLE 1-1.6 AMP NEW $59.99 |
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ALLEN BRADLEY 140M-C2E-B16 MOTOR PROTECTION CIRCUIT BREAKER 3 POLE 1-1.6AMP NEW* $53.99 |
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Westinghouse HMCP015E0C Motor Circuit Protector/Breaker, 15 Amp, 600 VAC/250 VDC $24.00 |
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Westinghouse HMCP030H1C Motor Circuit Protector/Breaker, 30 Amp, 600 VAC/250 VDC $39.00 |
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Westinghouse HMCP007C0C Motor Circuit Protector/Breaker, 7 Amp, 600 VAC/250 VDC $24.00 |
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Westinghouse HMCP003A0C Motor Circuit Protector/Breaker, 3 Amp, 600 VAC/250 VDC $18.00 |
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CUTLER HAMMER MOTOR CIRCUIT PROTECTOR 50 AMP GMCP050 $54.99 |
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Westinghouse Motor Circuit Protector HMCP003A0C 3 amp $4.00 |
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Cutler Hammer Motor Circuit Protector 30 AMP 600V C370MCP0 GE NIB $1559 Reta $149.99 |
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SIEMENS FXD63A150 150 AMP MOTOR CIRCUIT INTERRUPTER ,USED w/ DAMAGE $75.00 |
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SIEMENS MOTOR CONTROL CIRCUIT NIB 40-50 AMP 3RV1-314HA10 50HZ TRIPS GOOD , NEW $75.00 |
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Westinghouse HMCP400X5 Motor Circuit Protector 400 AMP $650.00 |
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New OEM Maxi-Type 30 Amp Circuit Breaker GM 12077843 $9.99 |
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GENERAL ELECTRIC TEC36150 150 AMP MAG BREAK MOTOR CIRCUIT PROTECTOR ,NIB $150.00 |
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Minn Kota MKR-19 Trolling Motor Circuit Breaker. $45.99 This fully waterproof circuit breaker protects the trolling motor from electrical damage.60 Amp rating with manual reset.Compatible with all 12, 24 and 36V systems.EAN/Barcode: 0029402023554.Free delivery by post. |
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Motorguide 50 Amp Manual Reset Circuit Breaker $22.99 Motorguide 50 Amp Manual Reset Circuit Breaker . Protects your motor and boat wiring. The 50-Amp breaker works with the new high thrust, high performance motors. |
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100 AMP CIRCUIT BREAKR $36.19 100 AMP CIRCUIT BREAKR |
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30 AMP CIRCUIT BREAKR $3.75 30 AMP CIRCUIT BREAKR |
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40 AMP CIRCUIT BREAKR $3.61 40 AMP CIRCUIT BREAKR |
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80 AMP CIRCUIT BREAKR $37.64 80 AMP CIRCUIT BREAKR |
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150 AMP CIRCUIT BREAKR $36.19 150 AMP CIRCUIT BREAKR |
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50 AMP CIRCUIT BREAKR $3.61 50 AMP CIRCUIT BREAKR |
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20 AMP CIRCUIT BREAKR $3.75 20 AMP CIRCUIT BREAKR |
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150 AMP MARINE CIRCUIT $55.03 150 AMP MARINE CIRCUIT |
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100 AMP MARINE CIRCUIT $55.03 100 AMP MARINE CIRCUIT |
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100 Amp Marine Circuit $50.99 STINGER SCBM100 MARINE CIRCUIT BREAKER (100 AMP) |
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150 Amp Marine Circuit $50.99 STINGER SCBM150 MARINE CIRCUIT BREAKER (150 AMP) |
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30 Amp Circuit Breaker $3.99 30 Amp Circuit Breaker. Incl. Mounting Bracket. In-Line. |
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40 Amp Circuit Breaker $3.99 40 Amp Circuit Breaker. Incl. Mounting Bracket. In-Line. |
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20 Amp Circuit Breaker $3.99 20 Amp Circuit Breaker. Incl. Mounting Bracket. In-Line. |
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100 Amp Circuit Breakr $29.99 COOPER BUSSMANN PF-200R CIRCUIT BREAKER WITH MANUAL RESET (100 AMP) |
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150 Amp Circuit Breakr $30.99 COOPER BUSSMANN PF-300R CIRCUIT BREAKER WITH MANUAL RESET (150 AMP) |
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Snetterton Motor Racing Circuit $70.1 High Quality Content by WIKIPEDIA articles Snetterton Motor Racing Circuit is a motor racing circuit in Norfolk, England. It is situated on the A11 road some 20 km northeast of the town of Thetford and 30 km southwest of the city of Norwich. The circuit is named after the village of Snetterton, which lies about 2 km to the northwest of the circuit, although much of the circuit is actually in the adjoining civil parish of Quidenham.In October 2005, it was announced by the owner of the circuit; Jonathan Palmer of MotorSport Vision, that the circuit would undergo extensive rebuilding work, in order to lengthen the circuit, and improve its facilities. Snetterton originally started off life as an RAF airfield (RAF Snetterton Heath) which was then designated for use by the United States Army Air Force. The airfield was opened in May 1943 and closed down in November 1948. Author: Surhone, Lambert M./ Timpledon, Miriam T./ Marseken, Susan F. Binding Type: Paperback Number of Pages: 92 Publication Date: 2010/07/28 Language: English Dimensions: 6.00 x 9.00 x 0.22 inches |
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Stinger / 100 AMP MARINE CIRCUIT / SCBM100 $59.77 Stinger – 100 AMP MARINE CIRCUIT – SCBM100 |
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Stinger / 150 AMP MARINE CIRCUIT / SCBM150 $60.08 Stinger – 150 AMP MARINE CIRCUIT – SCBM150 |
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Motor & Generator Kit $25.95 Electronics Motor & Generator Action Kit. Build your own operating motor, Find out how a generator makes the electricity that makes things work. Requires two AA batteries. Ages 8 & Up. |
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MINN KOTA 1865106 MINN KOTA MKR19 60A CIRCUIT BREAKER WATERPROOF $53.14 The Minn Kota 1865106 MKR19 waterproof circuit breaker protects the trolling motor from electrical damage. It features a 60 amp rating with manual reset and is compatible with all 12 24 and 36volt systems. |
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Minn Kota 1865106 MKR-19 60A Waterproof Circuit Breaker $53.99 “Minn Kota MKR-19 Waterproof Circuit Breaker, The Minn Kota 1865106 MKR-19 waterproof circuit breaker protects the trolling motor from electrical damage. It features a 60 amp rating with manual reset, and is compatible with all 12-, 24- and 36-volt systems. 1865106 Features: Product # 1865106, Circuit Breaker, 60 Amp Rating w/ Manual Reset, Waterproof, Compatible w/ All 12, 24 & 36-volt Systems” |
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Briggs and Stratton 71047 100 Amp 16 Circuit Transfer Switch $549.99 100 Amp 16 Circuit Transfer Switch – 71047 |
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Littelfuse CCMR007 CCMR Series – Class CC Dual Element Time Delay Fuse for Short-Circuit Protection of Motor Branch-circuits $12.04 Littelfuse CCMR007 CCMR Series – Class CC Dual Element Time Delay Fuse for Short-Circuit Protection of Motor Branch-circuits Recognized as one of the world’s leading providers of circuit protection solutions, Littelfuse is the first choice of design engineers and purchasing managers worldwide. At Littelfuse, they focus on what they do best- developing and manufacturing devices that protect electronic circuits and applications from harm caused by overcurrent and overvoltage events. It’s this focus that has enabled them to consistently lead the industry in innovative, high-quality circuit protection solutions. Littelfuse CCMR007 CCMR Series – Class CC Dual Element Time Delay Fuse for Short-Circuit Protection of Motor Branch-circuits Features: Technology: Leaded and Cartridge Package Type: Pkg Type: Industrial Cartridge Mount Method: Mount: Fuse Block / Clip / Holder Current Rating: Amp Rating (A): 7.0000 Package Size / Form Factor: Form Factor: Class CC UL Fuse Class: Fuse Class: Supplemental Norminal Melting I2t : I2t (A2 Sec) Fuse Opening Characteristic: Opening Characteristic: Slo-Blo Nominal Cold Resistance: Resistance (Ohms): 0.036899999 Voltage Rating: Voltage Rating (V): 600 Certifications: Cert Interrupt Ratings: IR: 20000A @ 250V 200000A @ 600V |
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Littelfuse CCMR015 CCMR Series – Class CC Dual Element Time Delay Fuse for Short-Circuit Protection of Motor Branch-circuits $11.23 Littelfuse CCMR015 CCMR Series – Class CC Dual Element Time Delay Fuse for Short-Circuit Protection of Motor Branch-circuits Recognized as one of the world’s leading providers of circuit protection solutions, Littelfuse is the first choice of design engineers and purchasing managers worldwide. At Littelfuse, they focus on what they do best- developing and manufacturing devices that protect electronic circuits and applications from harm caused by overcurrent and overvoltage events. It’s this focus that has enabled them to consistently lead the industry in innovative, high-quality circuit protection solutions. Littelfuse CCMR015 CCMR Series – Class CC Dual Element Time Delay Fuse for Short-Circuit Protection of Motor Branch-circuits Features: Technology: Leaded and Cartridge Package Type: Pkg Type: Industrial Cartridge Mount Method: Mount: Fuse Block / Clip / Holder Current Rating: Amp Rating (A): 15.0000 Package Size / Form Factor: Form Factor: Class CC UL Fuse Class: Fuse Class: Supplemental Norminal Melting I2t : I2t (A2 Sec) Fuse Opening Characteristic: Opening Characteristic: Slo-Blo Nominal Cold Resistance: Resistance (Ohms): 0.007080000 Voltage Rating: Voltage Rating (V): 600 Certifications: Cert Interrupt Ratings: IR: 20000A @ 500V 200000A @ 600V |
Polyphase Induction Motors
About two-thirds of the electric power in the U.S. is consumed by motors, with industrial three-phase motors above 5 HP (7 kW) being by far the bulk of that load. They are linear loads and therefore don’t contribute to harmonics. They are, however, the major contributor to reduced Displacement Power Factor, which is a measurement of the effective use of system capacity.
Measurements
1. Voltage unbalance
Voltage unbalance should not exceed 1-2% (unless the motor is lightly loaded). Why such a small number? Voltage unbalance has a very large effect on current unbalance, in the neighborhood of 8:1. In other words, a voltage unbalance of 1% can cause current unbalance of 8%. Current unbalance will cause the motor to draw more current than it otherwise would. This in turn causes more heat and heat is the enemy of motor life, since it deteriorates the winding insulation.
2. Voltage %THD and harmonic spectrum
Voltage THD should not exceed 5% on any phase. If the voltage distortion on any phase is excessive, it can cause current unbalance. The usual culprit is the 5th harmonic and therefore the harmonic spectrum should be examined for the 5th in particular. The 5th is a negative sequence harmonic which creates counter-torque in the motor. A motor fed by a voltage with high 5th harmonic content will tend to draw more current than otherwise. This is a major problem when across-the-line or soft-start motors share the same bus with ASDs.
3. Current unbalance
To find current unbalance, measure amps in all three phases. Do the same calculation as for voltage unbalance. In general, current unbalance should not exceed 10%. However, unbalance can usually be tolerated if the high leg reading doesn’t exceed the nameplate FLA (Full Load Amps) and SF (Service Factor). The FLA and Service Factor are available on the motor nameplate. If the voltage unbalance and the voltage THD are within limits, high currentunbalance can be an indication of motor problems, such as damaged winding insulation or uneven air gaps.
Current measurement will also find single-phasing. If a three-phase motor loses a phase (perhaps caused by a blown fuse or loose connection), it may still try to run single phase off the remaining two phases. Since the motor acts like a constant power device, it will simply draw additional current in an attempt to provide sufficient torque. A voltage measurement alone will not necessarily find this condition, since voltage is induced by the two powered windings into the non-powered winding.
4. Loading
Measure current draw of the motor. If the motor is at or near its FLA rating (times the Service Factor multiplier), it will be more sensitive to the additional heating from harmonics, as well as current unbalance. A motor that is only lightly loaded is usually safe from overheating. On the other hand, its efficiency and DPF are both less than optimal. Most motors reach maximum efficiency at 60%-80% of full load rating. Displacement Power Factor is maximum at rated load (including S.F.) and drops off, especially at less than 80% of rated load. This leads to the conclusion that, to the degree a motor load is constant and predictable, 80% of rated load is the most efficient operating range.
5. Inrush
Motors which are started across-the-line (as opposed to those using soft-starts or drives) draw a current inrush, also called locked rotor current. This inrush tapers off to normal running current as the motor comes up to speed.
• Older motors draw an inrush of typically 500-600% of the running current. Newer energy efficient designs draw brief inrushes as high as 1200% of running current, a direct result of the lower impedances which help make them more energy efficient in the first place.
• High torque, high HP motor loads require proportionally higher inrush.
• Motor loads started at the same time will have a cumulative inrush.
Another source of inrush is UPS and ASD systems with diode converters. They draw inrush current as their cap banks first charge.
Effects of inrush current
1. Inrush causes voltage sags if the source voltage is not stiff enough:
• Relays and contactor coils might drop out (typically, the sag would have to get as bad as about 70% of normal line voltage); or, if they hold in, their contacts might chatter (especially if the additional load causes a long-term undervoltage).
• Control circuits might reset or lock up (at 90% and below).
• Drives might trip off-line (undervoltage trip).
2. High peak demand periods, which may cause higher utility bills.
3. Cycling loads can cause periodic sags, which might show up as flickering lights.
4. If the motor is required to start up a high torque load, the inrush can be relatively prolonged (e.g., 10 to 20 seconds or more) and this can cause nuisance tripping as the overload heaters trip the motor starter.
6. Power Factor
To size PF correction capacitors, it is necessary to measure the DPF (Displacement PF) and Active Power consumption (kW) of the motor load. These measurements assume that the motor voltage and current is balanced. Therefore, before undertaking PF correction, first make sure that voltage and current unbalance are within limits. Either problem can shorten motor life and should take priority over DPF correction.
Fluke Corporation offers an extensive range of power quality test tools for troubleshooting, preventive maintenance, and long-term recording and analysis in industrial applications and utilities. For more information on Fluke Predictive Maintenance Products and Services go to http://www.fluke.com/pdm
About the Author
Steve Glad is a writer with Structured Information (http://www.strucinfo.com/) in
Arlington, MA. He frequently writes about industrial technology topics.