Depending on the equipment associated it could readjust the allowable breaker size. Be recommend that basic purpose circuits are restricted to a 20 amp maximum. What function are friend considering this circuit for?

Originally post by md2lgyk

what go the nameplate on the well pump say? In other words, whats the HP? girlfriend dont constantly size the breaker by the wire size, through motors, you can easily have a lot bigger breaker than wire size.

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Is her well pump convertible come 240 volts? If for this reason you would certainly downsize the wire dimension as the ampacity would be reduced in half. This might save you money ~ above the materials. Normally #8 is an excellent for 40 amps. Wires can also be up size to allow for voltage drop because of long circuit distances while the breaker sizes remain the same. Once this happens the floor wire typically needs to it is in upsized together well.
Okay, a 1.5 HP engine at 115 volts the complete Load current (FLC) is 20 amps, (table 430.148 NEC) to number out brief circuit and ground fault security you take it 250% x FLC, so 250% x 20 (FLC) = 50 amps, this is her circuit breaker size. Currently to uncover out the conductor dimension you take it 125% x FLC, therefore 125% x 20 (FLC) = 25 amps, so at least #10 AWG is required. So, for your pump, you need a 50 amp breaker, and also a minimum wire dimension #10 AWG. You currently ran # 8, so simply install a 50 amp breaker and your all set.
There one thing I have tiny condersaton with well pump motor I understand you mention 120 v and also how far is the pump is ?? and also the various other thing you might run into this case is the you may have tough time to find a solitary pole 50 amp breaker. Yes they are around but if your big box save don\"t share this inspect out the electric supply centre.Merci,Marc
The pump is set at 640 feet. I guess that\"s why it requirements such a big motor. And also I recognize what you mean about finding a breaker.
The pump is set at 640 feet. Ns guess that\"s why it needs such a big motor. And also I understand what you mean around finding a breaker.
Just use a 2 pole breaker, clear your only going to use 1 leg, but there is naught wrong through that.
20% voltage autumn is i can not accept at that distance. You will need a #2 copper conductor to deliver motor operation voltage at 640 feet presume your beginning with 120 volts in ~ the panel.I would refer ago to computer BOSS asking if the motor deserve to be wired 240 volts. This would minimize motor amperage come 10 amps. Your #8 would certainly then supply operating engine voltage.
I ran the numbers with my caluator and you will require much larger wire size to take care of the voltage drop for this distance friend will finish up require #0 or 1/0 cable to store the voltage drop withen 2.5% selection to be this fine motor is submersable or surface placed motor ?? if latter it will certainly pretty easy to swap end 240 volts through 240v 1.5 HP engine you will need #6 wire dimension that based on 2.5% again so over there is a big diffrence if friend think we are kidding on the just gain anlog voltmeter and also when the pump is to run at the well head you will see how much voltage it will certainly drop. The larger the voltage fall the more tough the motor have to overcome it and also it will automatically draw more current to store up.Merci,Marc
Motors are rated at 115/230 volts, frequently this is about 5% drop native what the calculators usage at 240 volts. If you use 5% drop in the calculator you will stay consistent with the wire dimension charts because that well pump electric motors specified by the manufacturers.A 115 volt engine is no acceptable at 640 feet both in price of wire to deliver rated voltage and design.
Now I\"m confused. The pump (a submersible) to be selected and also installed by a big professional pipes contractor. They also told me what dimension of wire to get. I have to think they knew what they to be doing.

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I think I\"ve discovered the resource of few of the confusion. Ns pulled the end the contractor\"s quote and also got the part number of the pump (Goulds 5SG15422C). Follow to the specifications from their website, that is a 230V pump, not 115V. So ns think there\"s a failure in the quote.Assuming that is indeed a 230V pump, I intend the recommended 50A breaker is also big? Goulds\" motor Application and also Installation Data claims 30A.
Now if the the situation if the is shown that motor is a 240 volts., then you have actually to adjust the breaker rating under to max that 30 amp normally i used 20 or 25 amp depending on which manufacter it have actually and also the wire you have hidden which you stated #8 that will job-related for that street it will be nice close come the max VD border I came up 4.1% therefore you room ok with that Merci,Marc®, started in 1995, is the leading independent home improvement and fix website. We welcome her comments and suggestions. All information is provided \"AS IS.\" Website operation problems call webmaster