Single Phase or 3phase power Info please

[duramaximizer]

I am looking into putting an irrigation system for farm use that will likely require 40-60hp to run the pump for the well depending on how deep it needs to be. 3 phase power is recommended, but will be costly to get it to my place. I am just wondering what my options are and is it worth it to run 3 phase over a roto phase or what other options do I have?

 

[matt78]

Im no expert but I do mechanical service on pumps, chillers, fans, etc. Motors of that size are 3phase. I dont know if there is a single phase motor that large. Sorry I cant help more than this. 214-631-1188, t gray electric, motor rewind shop and new motor sales here in dallas. You can ask for counter sales and see what they say.

 

[THEFERMANATOR]

The electric cost would eat you alive if you could find a single pahase motor big enough to run it. Not to mention the added starting torque of the 3 phase over the single phase motor. And phase converters for that large of a load would probably be rather inefficient driving your electrical costs even higher.

 

[DIESELMAFIAPER.LB7]

If you can swing 3 phase do it it's better will run less amps then a single phase the pump prices shouldn't be to much different if not cheaper for 3 phase iirc but I'd really try and go 3 phase it is a lot better

 

[Big Chris]

Look into a phase converter to create three phase power from single phase. Depending on which brand irrigation system you use the pivot will probably need 3p as well. TL pivots can be bought with a small Isusu diesel to run the pivot hydraulic pump that operates the pivot. The electronic controls are DC. Save money on wire but you are burning diesel.

 

[Big Chris]

Treed.

 

[RickDLance]

You will loose approx 1/3 the rated hp of the motor and even more on start up if you run it on a converter. We run on a couple here because the cost to bring 3 phase in was astronomical.

 

[Fingers]

There are very few 2-3 phase converters that size. None of them efficient. The cost to run would be similar to running a diesel pump. If you are going to go electric, you will need to get the 3 phase service.

However, it all comes down to the expected run time you are going to use the pump for. Setup for the diesel is minimal and economical for relatively short run times. You will have to do the math.

 

[Fingers]

BTW, a decent 3 phase gen set is a nice go between. Serves as back-up power AND runs the pump.

 

[matt78]

If you get 3phase might as well get 460 volt, wire is cheaper and most motors are dual voltage.

 

[duramaximizer]

I have to go 1.5 miles at a cost of $18,000 for 3 phase. IDK how much a generator costs, but I wish the local coop wasn't in a "territory", because another company has a substation less that 1/4 mile from me but can't sell me power.

 

[jkholder09]

Get a vfd drive

It converts 240 to 3 phase.

Variable frequency drive

from mobile

 

[mike diesel]

A 60 horse motor is going to be strictly 3 phase. Single phase motors are only about 10 horse at there biggest and starting a 10 horse motor on single phase will be slow and noisy at best. Turning a water pump would require a substation amount of starting torque which only 3 phase can supply. Also 3 phase 480 would pretty much be the only thing I would run 60 horse motors on. The amperage to start a 60 horse motor on 240 volt would be pretty high.

Fingers idea of a 3 phase gen set would be my suggestion also. Can pick up old huge military diesel gen sets for pretty cheap. Far less than 18k.

And if your not needing to control motor speed, I don't think a VFD is what your looking for.

 

[DIESELMAFIAPER.LB7]

240v and 60hp lol

 

[matt78]

You dont need a vfd. All a vfd does is speed up and slow down an electric motor based on load of lets say air pressure for a blower, water pressure, or for temp control on lets say a cooling tower fan. It does not make 240volt 3 phase. It is a soft start for one instead of a across the line start, which is what you have if you have a basic motor starter. Unless you need to regulate the discharge pressure on your pumps a vfd is a waste, plus you would have to have a pressure sensor that used a 0-10 volt dc or 4-20 milliamp signal to speed up and slow down the drive, if you didn't you would have to control it manually.

 

[matt78]

Also a vfd can run a standard 460 volt 60hz motor at anywhere from 1-60 hz. It ramps the 3phase voltageup and down, it is ssupposed to save energy on electric motors more so in a low load condition. Google abb, yasakawa, siemens, etc. They all make vfd's.

 

[McRat]

Wow ... Do you really need 60HP for a well???? That's a huge fricken motor.

I would find out more info why that much HP is needed. Even 3ph is going to eat you alive in electric costs. 50kWh * .20/kWh is $10 per hour that it is running.

$240 a day for continuous use?

 

[McRat]

PS - If there were such a thing as a single phase 240v 50kW motor, that's more than 200 amps. 460v would still be 100 amps.

 

[dmax711]

Anytime you have the option to use higher voltage or 3phase you should do it. So much more efficient. I'm sure you could find a nice natural gas generator for well under that 18k mark. To give u an idea I just did a whole house generator for a massive place on a lake down here. Had 2 200 amp panels and the guy wanted to run everything in the entire joint if he lost power. The generator we specd out was about 13 grand and was very quiet.

 

[duramaximizer]

Yeah, I need a VFD for my swing arm too. It's looking like I will need at least 800gpm continuous flow of water out of a 10" well to keep things operational. They said if the well wasn't super deep, I could get by with only a 40hp. This is hopefully only seasonal use and approximately 200 hours run time a year.

I don't have a pipeline for natural gas on the property, but with in a 1/2 mile there is a pipeline I could get ran if it was feasible. I could use propane/diesel, I am just wondering how efficient a generator is to run in a cost per KWH.