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Proper Gauge wire for 3 motor vacs

Scott220

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Looking to upgrade from 2 motor to 3 motor vacs. Currently running approx. 80-100’ of 12 gauge wire on 20 amp breakers on the current 2 motor vacs. Any possibility of just going with 30 amp breakers and staying with 12 gauge opposed to 10 gauge? The 3 motor vacs pull 24 amps. Previous electrician said to have had a tough time pulling wire so I dread running into a problem pulling new wire if it could work.
 

Eric H

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Do NOT use a 30 amp breaker with 12 ga wire. You’ll have no protection at all.
Ideally, you would pull new 10ga.
what size conduit do you have? How many vacs does each conduit serve?
 

OurTown

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I would suggest trying to pull new 10 gauge wire first before committing to new 3 motor vacs. Putting a 30 amp breaker on 12 gauge is against code and could cause a fire.
 

Scott220

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Each vac has its own conduit. I’ll have to check size of conduit. Appreciate your input!
 

I.B. Washincars

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Jim Gosnell told me several years ago that he devised something for this scenario. IIRC, two of the motors start and get up to speed, shut off momentarily as the third starts, then restarts the others while they are coasting, keeping the amp draw at less than 20A. I'm thinking all of this happens within a second or so.
 
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OurTown

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Jim Gosnell told me several years ago that he devised something for this scenario. IIRC, two of the motors start and get up to speed, shut off momentarily as the third starts, then restarts the others while they are coasting, keeping the amp draw at less than 20A. I'm thinking all of this happens within a second or so. I
We have a JE Adams vac that does something similar but starts just one at first and then the second and then the third if turbo is selected.
 

OurTown

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Can it do that using #12 wire?

I think it just keeps the start up amp spike down. It is on a 25 Amp breaker and has never tripped. I'll check the amp draw with a clamp on meter if I can remember to do it.
 

tdlconceptsllc

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Remember also a High leg site will pull less amps also like a true 230 site vs a 208v site. I had to cut the parking up at my wash to instail 10 gauge wire it sucks older washes always have 12
 

wash4me

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I agree with others it is wrong to put a 12 gauge wire on a 30 amp breaker. That being said it will work and you do still have some protection on the wire. Unlikely to cause a problem.
 

cmawash

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JUST FINISHED UPGRADING WIRE TO 8 GAGE HAD SOME 12 AND 10 GAGE, LUCKELY THE CONDUIT WAS BIG ENOUGH , GOT RIDE OF A LOT OF SPICES, SUB GAGE WIRING AND UPGRADED GROUNDING. EQUIPMENT OPERATION WAS NOTICEABLE
 
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