3 Phase Motors running on single phase
3 Phase Motors running on single phase
(OP)
I need to change 2 pool pump motors running on 3 phase to single phase. they are 240/380 volt running at 2850 rpm. I know it can be done using 2 capacitors, but how do you calculate the size of the capacitors?






RE: 3 Phase Motors running on single phase
RE: 3 Phase Motors running on single phase
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If we learn from our mistakes I'm getting a great education!
RE: 3 Phase Motors running on single phase
RE: 3 Phase Motors running on single phase
Is there a difference?
Gunnar Englund
www.gke.org
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100 % recycled posting: Electrons, ideas, finger-tips have been used over and over again...
RE: 3 Phase Motors running on single phase
An inverter is a component of a VFD.
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RE: 3 Phase Motors running on single phase
There may be some dispute about that. I am sure Scotty meant a complete VFD. Free-standing inverters for motors are not very common or practical. Nor are they dirt cheap.
Gunnar Englund
www.gke.org
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100 % recycled posting: Electrons, ideas, finger-tips have been used over and over again...
RE: 3 Phase Motors running on single phase
About the only answer you will get on this site is to use a Variable Frequency Drive suitable for a single phase input.
It is possible to run three phase motors on single phase with capacitors. If your pumps are closely matched to your motor sizes you may have problems getting full output from the motors. If the currents are not balanced, the motor will generate more heat. This extra heat from unbalance will limit the maximum load that the motor can pull.
If you are determined to use three phase motors on single phase, try the Do It Yourself forums and/or hobby forums. There you will find people with hands on experience with running three phase motors on single phase with capacitors.
Bill
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"Why not the best?"
Jimmy Carter
RE: 3 Phase Motors running on single phase
Example:
http://ww
Keith Cress
Flamin Systems, Inc.- http://www.flaminsystems.com
RE: 3 Phase Motors running on single phase
I didn't realize just how cheap VFDs were getting.
Thanks
Bill
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"Why not the best?"
Jimmy Carter
RE: 3 Phase Motors running on single phase
Yes, you know what I mean.
Stevenal,
You are right too. The two terms are (incorrectly) used pretty much interchangeably in colloquial discussion among people who use / install / repair them. I would be more careful in a written specification. Is it different in the US?
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If we learn from our mistakes I'm getting a great education!
RE: 3 Phase Motors running on single phase
RE: 3 Phase Motors running on single phase
'Twas careless on my part - I will pay more attention in future.
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If we learn from our mistakes I'm getting a great education!
RE: 3 Phase Motors running on single phase
Keith Cress
Flamin Systems, Inc.- http://www.flaminsystems.com
RE: 3 Phase Motors running on single phase
Inverters came first as a general technology in the mid '60s, AC Drives that used inverters in them came much later. Here in the US, one of the first commercially available PWM drives was the "Parajust", made by Parametrics and they actually copyrighted the term Adjustable Frequency Drive (AFD). Subsequent competitors used the term Variable Frequency Drives (VFDs) from the outset because of our penchant for TLAs. Later when the Japanese (Yaskawa, Toshiba, Mitsubishi) entered the VFD market big time in the mid '80s, they had marketing departments who translated their Japanese marketing materials directly to English rather than hire US marketing professionals. Because of the language differences, TLAs meant nothing to them so they put out marketing campaigns that called them "Inverter Drives" (as opposed to mechanical drives I suppose) since that is what their Japanese terminology translated to best. Since they became dominant very quickly and are largely responsible for the explosion in use and acceptance, the terminology stuck with us as an industry, but we (being largely a linguistically lazy lot) just shortened it to "Inverters".
I gave up correcting people years ago though. I was accused of being pedantic and really, we all know what we are talking about by context anyway don't we?
RE: 3 Phase Motors running on single phase
Gunnar Englund
www.gke.org
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100 % recycled posting: Electrons, ideas, finger-tips have been used over and over again...
RE: 3 Phase Motors running on single phase
Many thanks
Ernest
RE: 3 Phase Motors running on single phase
Keith Cress
Flamin Systems, Inc.- http://www.flaminsystems.com
RE: 3 Phase Motors running on single phase
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If we learn from our mistakes I'm getting a great education!