watts ( amps ) for 1hp pump

Soundguy · Aug 5, 2008

I just had a well drilled out on a remote pasture, and I'll be waiting about a month for the power co to get power out there.

I plan on taking my pto generator out there so i can power the well so i can pressure test the pvc line for the cattle waterers before I cover the trench up.. any electrician here give me an idea of the wattage needed for a 1/4 hp submersable? I know the small pole the contractor set is a 60amp meter base.. etc..

soundguy

Highbeam · Aug 5, 2008

1/4 HP is teensy. Are you sure it is not a 3/4 HP or even 1HP?

Technically, one HP is equal to 746 watts. But this being a motor you will have a surge at the beginning of say 3x, so for 0.25 HP I would assume a 1000 watt genset will do the whole job. A typical well pump is wired with 220 volts so the standard 20 amp circuit would be appropriate with 12 gauge wires. If this little 1/4 HP pump is 110 volt then you could downsize to a 15 amp circuit with 14 gauge wires.

How deep is the well? The 60 amp panel he is setting is probably the smallest he could find.

Mickey_Fx · Aug 5, 2008

1/4HP? Well, for a 1 HP pump, steady state is going to be in the range of 900W accounting for efficiency losses. As stated, staring loads are going to be a lot higher.

With that said, I've ran my 1HP pump, wired for 110V off my 4kw genset in the RV. You could really hear the starting load by the way the genset responded. After starting, no problem running the load for as long as the fuel supply lasted.

Soundguy · Aug 5, 2008

I'm not sure why i said 1/4 hp in the message, but it is 1hp.. I looked at the pole, and it is a 60a box, has a 20a 120v recep in a 'wet' box, and then the well is wired 220 with one of those ganged 20a breakers.

I have a 12.5 KW pto genset.. so i think I will be good for power then.

I am laying pipe for cattle water.. etc.. and want to be able to pressure test my lines and cover trenches instead of waiting a month for the power co to come out and finally run power from across the street, down the edge of my property to my pole.. etc.

thanks

from what you both say.. looks like I am -way- set power wise..

soundguy

J_J · Aug 5, 2008

Soundguy said:
I'm not sure why i said 1/4 hp in the message, but it is 1hp.. I looked at the pole, and it is a 60a box, has a 20a 120v recep in a 'wet' box, and then the well is wired 220 with one of those ganged 20a breakers.

I have a 12.5 KW pto genset.. so i think I will be good for power then.

I am laying pipe for cattle water.. etc.. and want to be able to pressure test my lines and cover trenches instead of waiting a month for the power co to come out and finally run power from across the street, down the edge of my property to my pole.. etc.

thanks

from what you both say.. looks like I am -way- set power wise..

soundguy

I believe that you can test your pvc lines with an air fitting and gage installed. Just cap off any line you want to test, and put say 30 or 40 lbs of air in the lines and if it holds for about 4 hrs, the line should be good. Temperature might change the reading a little. You can also apply soapy water to all the joints to test for leaks. I always use a cleaner and a light coating of glue. The blue stuff has a quick set up.

Soundguy · Aug 5, 2008

I'll be using the blue glue.. I like it. I might as well water test them, as I'll have to have power to do an air test as I don't have an air tank with big enough capacity to pressure test 500' of line.

soundguy

RonMar · Aug 5, 2008

You can use air, but best practice is not to on an unproven system, as any issue can lead to a violent decompression. There was a man killed up here in my area a few years back. He was walking thru a pasture and kicked an irrigation standpipe comming up out of the ground. The pipe was capped and under pressure(large air pocket in the system). His kick was enough to dislodge the cap, which was propelled into his head by the escaping air, and dropped him on the spot...

J_J · Aug 6, 2008

Ron.

You should be aware that air is what the plumbing inspectors use to test and approve new homes plumbing. This is because they do not have water hooked up yet. Since Schedule 40 PVC is rated at around 320 lbs, you can put more air pressure in than water pressure. Most water systems are between 30 and 60 lbs pressure. So yes, I believe air is the preferred method of testing water lines.

Soundguy · Aug 7, 2008

It'll be easier for me to just use water as i will have the genny on site. I opted for the thicker 600psi pipe vs the 315 thinner pipe.. was only 9$ more for the thicker pipe looking at near 500'.. i figured it was worth it.. etc.

soundguy