3 phase to single phase
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URL: https://www.allischalmers.com/forum/forum_posts.asp?TID=158911
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Topic: 3 phase to single phase
Posted By: FREEDGUY
Subject: 3 phase to single phase
Date Posted: 09 Mar 2019 at 6:03pm
Can a 3 ph motor be converted "easily" to single phase? There is an A/C advertised locally that is currently wired for 3,but we only have single and not interested in a converter. Thanks
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Replies:
Posted By: Kenny L.
Date Posted: 09 Mar 2019 at 6:49pm
You should be able too, Google it or do a search of Dave Kemp post.
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Posted By: marion
Date Posted: 09 Mar 2019 at 7:40pm
Posted By: JW in MO
Date Posted: 09 Mar 2019 at 8:01pm
What Marion said, only IN ALL CAPS, NOOOOOO. That's the quickest death of a 3 phase motor, lets the smoke out pretty quick and the fire might last a while.
------------- Maximum use of available resources!
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Posted By: jaybmiller
Date Posted: 09 Mar 2019 at 8:10pm
no, unless you ADD a converter..(to change single phase into 3 phase)
depending on the HP ,might only cost $50-$200 for the 'magic black box'.
------------- 3 D-14s,A-C forklift, B-112 Kubota BX23S lil' TOOT( The Other Orange Tractor)
Never burn your bridges, unless you can walk on water
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Posted By: LeonR2013
Date Posted: 09 Mar 2019 at 9:02pm
There you go Freedguy. All the answers you could ever want. How some ever, perhaps I can clarify that a bit for you. My son who is a knife maker decided to get a new belt grinder. It came with a 3ph. motor with instructions on how to run a single phase to it to make it work. He and I being the dummies we are said this can't be so tough, so we went to work. We ran wiring, put in all the boxes, mounted everything, stood around the corner and turned it on. Son of a gun. It worked! Perfectly! Still does three years later. But you need that little black box that converts that single phase 220 to 3 phase so you motor won't burn up. By the way it's also variable speed. Now the next problem. The grinder came as a package deal and I Have no idea where you can get the little black box but I'm sure if you let your fingers do the walking they'll pop up like mushrooms. Don't give up. Leon
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Posted By: ocharry
Date Posted: 09 Mar 2019 at 9:33pm
I use a VFD ....variable frequency drive for my lathe and mill
220 single goes in...220 3phase comes out...it is variable speed for my lathe and mill...but I guess you could just run it wide open if you wanted.....works pretty darn good for me
The are horse power specific so depends on how big a motor you drive how big a unit you need
They are pretty reasonable for what you get I guess
When I first got them I thought... No Way this thing will work...but they do a great job for me
My .02
Ocharry
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Posted By: steve(ill)
Date Posted: 09 Mar 2019 at 10:17pm
verify that the A/C is 220 v 3 phase and not 480 v 3 phase.... there is a difference... And if your A/C mean air conditioner, I don't think I would buy that and run off single phase.. Converters are made for TOOLS that you run part time... A beat up old 3 phase air conditioner is not a good plan.
------------- Like them all, but love the "B"s.
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Posted By: jaybmiller
Date Posted: 10 Mar 2019 at 9:03am
I was curious... https://www.banggood.com/2_2KW-220V-9_5A-1HP-To-3-Phase-Variable-Frequency-Inverter-Motor-Drive-VSD-VFD-p-1392464.html?rmmds=mywishlist&cur_warehouse=CN" rel="nofollow - https://www.banggood.com/2_2KW-220V-9_5A-1HP-To-3-Phase-Variable-Frequency-Inverter-Motor-Drive-VSD-VFD-p-1392464.html?rmmds=mywishlist&cur_warehouse=CN here's one 'magic box', NOTE, only rated for ONE HP. So I'd expect a 5HP one to be $250 range ? LOTS of 5HP 3PH motors.....so VFD should be economical... You could also lookup 'rotary converter'.. lots of ways to get 3PH from 1PH(well 2PH... 240 house power is 2 phase)
------------- 3 D-14s,A-C forklift, B-112 Kubota BX23S lil' TOOT( The Other Orange Tractor)
Never burn your bridges, unless you can walk on water
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Posted By: HudCo
Date Posted: 10 Mar 2019 at 11:25am
differant twist here we were talking to the power company about two weeks ago as to switching the shop to three phase since it already runs in front of us. havent got in to the cost of that yet
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Posted By: ocharry
Date Posted: 10 Mar 2019 at 12:02pm
Hud,,,where i used to live there was 3phz on the pole in front of the house
i contacted the power company about it and they would do it ,,,but,,,,what ever the max usage was,,, was what the bill would be whether you used it or not,,,so if you used 1500KW this month and didnt use it for the next 3 months at all,, you still payed for the 1500KW,,,,being i wasnt in business and that could very well be the case for me,, i just got a phase converter then,,,,
fast forward to now ,,,i have a VFD and it does very well for me,,,without any noise,,lol
just maybe something to ask them about,,,,the power companies are all different and that was a few years ago
just a thought
ocharry
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Posted By: allis g
Date Posted: 11 Mar 2019 at 8:05am
I have a Bridgeport mill and a lathe both are 3 phase The mill runs with a static phase converter the lathe runs with a rotary phase converter. Both work great. It’s got to do with the tork required to start and run. I bought the static and built my rotary .. got a big old 3 ph motor on the floor that generates the third leg.
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Posted By: ac fleet
Date Posted: 11 Mar 2019 at 12:15pm
I was told that the static converters will eat up the windings in the motors. I had one for a few weeks, temp. use, got scared and quit using the press. Have a rockwell 24" hyd. shaper with a box of some sort that I have never plugged in. I have it for sale since I can't get 3-ph.
I wouldn't trust the static converters too far or for extended run time.----just sayin---
------------- http://machinebuildersnetwork.com/
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Posted By: Coke-in-MN
Date Posted: 11 Mar 2019 at 1:34pm
Using a 15 HP 3 phase motor to run most of shop tools including a 7 1/2 HP Iron Worker 3 ph unit - 2 Bridgeports and couple other things , My large lathe in other side of main shop has 5 HP motor on Nichomori running on 3 HP rotary coverter , the Bridgeport in that shop has a box phase converter runnign the 3 ph motor Have 480 3ph across road on overhead lines feeding phone company central exchange building - Power company said to bring to my shop they would need to set 3 poles and 450 ft of overhead wire - $10,000 cost .
------------- Faith isn't a jump in the dark. It is a walk in the light. Faith is not guessing; it is knowing something. "Challenges are what make life interesting; overcoming them is what makes life meaningful."
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Posted By: nella(Pa)
Date Posted: 11 Mar 2019 at 1:54pm
allis g wrote:
I got a big old 3 ph motor on the floor that generates the third leg. |
It is not hard to generate 3phase with a three phase motor. Most, if not all of your motors will not be starting under load, that will help determine what size 3ph motor you will need. That is what I was going to do , but then I came across a rotophase that a friend used to run his corn dryer operation, it runs my shop well.
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Posted By: tadams(OH)
Date Posted: 11 Mar 2019 at 2:20pm
Got a friend that done it use another motor to convert it, not sure how but he runs an lot of machine in his shop.
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Posted By: farmboy520
Date Posted: 11 Mar 2019 at 2:44pm
Remember guys, he is asking if he can use a 3 phase motor on single phase.
------------- On the farm: Agco Allis 9695, 7060, 7010, R66, Farmall H, and Farmall F20 (Great Grandpa's)
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Posted By: nella(Pa)
Date Posted: 11 Mar 2019 at 3:57pm
farmboy520 wrote:
Remember guys, he is asking if he can use a 3 phase motor on single phase. |
Yes you can, you can use a starter bank of capacitors to start the motor and it will run at about 70% of it's power or you can run a 3phase motor on single phase to generate the third leg(not a true 3phase but it works quite well) for three phase.
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