Ask Experts Questions for FREE Help !
Ask
    John364's Avatar
    John364 Posts: 2, Reputation: 1
    New Member
     
    #1

    Feb 2, 2012, 05:46 PM
    Will a single phase motor use less power than a 3 phase motor?
    I am in the process of selecting a farm duty high torque 2 hp electric motor for a small "pilot mill rock "ore" crusher. At my house (garage) I only have 115v outlets. I have a friend that is a licensed electrician and he said he could come out and wire a 230v single phase outlet on a 30 amp breaker so I could use a 230v single phase motor I was interested in using. The motor has a manual overload protection circuit rated at 9.5 amps and rated at 14amps at full load @230V. It gets confusing because some websites selling motors that only show "nameplate amps". Now I also looked at 2 hp, 3 phase motors that the amps run @ 5.6 amps but I don't think that is at "full load" Anyway, if I could get my garage wired for 230v single phase and then use a VFD, is it possible to run a 3 phase motor? And would it be cheaper on my power bill compared to using the single phase motor that I have selected? Thanks for any and all help!

    P.S. I cut it twice and it's still too short! LOL
    tkrussell's Avatar
    tkrussell Posts: 9,659, Reputation: 725
    Uber Member
     
    #2

    Feb 3, 2012, 10:23 AM
    Neither the single phase or three phase is cheaper when both motors are 2 HP. If anything, single phase will run a bit less wattage.

    Nameplate amps is Full Load Amps.

    Many VFD's allow a 3 phase motor to be used on a single phase system, acts as a phase converter.

    There will be additional losses if a VFD is used to power a 3 phase motor on a single phase system.

    Stick with your electricians plan.
    John364's Avatar
    John364 Posts: 2, Reputation: 1
    New Member
     
    #3

    Feb 3, 2012, 02:28 PM
    Hello Tkrussell,

    My electrician's plan was to make 230v @ 30 amps available and install a "start stop motor switch" in line and then straight to the single phase,2hp,230v,14 amp. Electric motor (under 8ft.length of power cable). I had a feeling 3 phase power was going to cause a lot of headaches/issues and extra cost but just wanted to make sure I was going to follow the most efficient/cost effective route when selecting the right electric motor for the job...

    Thank you for your help!

    John
    Fr_Chuck's Avatar
    Fr_Chuck Posts: 81,301, Reputation: 7692
    Expert
     
    #4

    Feb 3, 2012, 03:22 PM
    If your home actually had 3phase power, ( which it would not) it is what almost all major industry use. But it can costs 1000's just to get 3 phase ran to a business. The last time I converted a workshop to 3 phase it was almost 10,000 and that was about 15 years ago.

    But when running on single phase either of your 2 hp will be about the same cost.

Not your question? Ask your question View similar questions

 

Question Tools Search this Question
Search this Question:

Advanced Search

Add your answer here.


Check out some similar questions!

Can a single phase 440v motor be run from a 3 phase 415v generator? [ 1 Answers ]

The motor uses the same 4 wire plug as a 3 phase system utilizing 2 x 220v actives to get the 440v.

Is it true that single phase motor takes more current than a 3 phase motor, if so why [ 2 Answers ]

A single phase air conditioner takes 8 amps, while the same with 3 phase takes only 3 amps, the billing is finally for the amps consumed right, so why not only 3 phase.

What is the difference between single phase and three phase motor [ 1 Answers ]

What is the difference between single phase and three phase motor


View more questions Search