| Author |
Message |
Ken O
Guest
|
 Posted:
Thu Oct 27, 2005 7:21 pm Post subject:
3 phase motor? |
|
|
Hello,
Just like to know if it was possible to convert from 1 phase to three phase
AC ?
See I have a motor that will run on 3 phase, and at hone I have only 1
phase. I would like to build a unit that will take three 1 phase, retard the
third and last phase 120 degree so it can turn my engine. Any comment will
be greatly appreciate
thank you
Ken O
|
|
| Back to top |
|
 |
Ken O
Guest
|
| Posted:
Thu Oct 27, 2005 8:27 pm Post subject:
Re: 3 phase motor? |
|
|
"Ignoramus21002" <ignoramus21002@NOSPAM.21002.invalid> wrote in message
news:56b8f.3816$Ty.2609@fe79.usenetserver.com...
| Quote: | On Thu, 27 Oct 2005 20:38:12 GMT, Roger Hamlett
rogerspamignored@ttelmah.demon.co.uk> wrote:
It is possible, but doing it with good power factor correction, and
safely, is hard work, and will involve a lot of time. Even on commercial
units, there are two basically different types. The type needed will
depend on the actual layout of the motor.
It is not at all difficult, I did it basically in two evenings (I was
interrupted by family and had to ask questions on newsgroup).
The simpler/cheaper type, does it in solid state, and is dependant on a
motor that has star windings, not delta windings. The second form
includes
transformer coupling, or a rotary converter, and is more expensive. Units
are made by companies like LG, Toshiba, Westinghouse, Hyundai etc.. Look
at:
http://www.3-phaseconverter.com/Inverter.html
Generally the better units, also offer you the option of operating the
motor at different speeds, and ramping acceleration/deceleration as well,
giving more flexibility, and less droop on the incoming supply when
starting. You could not even buy the parts to build such a unit, for the
prices they sell for, especially on places like Ebay.
My 10 HP rotary phase converter cost me $45 in parts. Granted, I am
pretty good at getting stuff cheaply. For a more regular person, who
would buy a used 3 phase motor for about $5 per HP at a local scrap
company, and caps on ebay, the cost would be about $80 or so, plus
electric wiring costs -- all those cables, circuit breakers etc, that
you have to buy regardless of whether your RPC is homemade or store
bought.
http://igor.chudov.com/projects/Phase-Converter/
This is a perfect home project where not many things can go wrong that
are not easily corrected.
|
Thanks for the tips. I will look into that.
I also omitted that I need 550 volts to tun this baby.
ken O |
|
| Back to top |
|
|
Ignoramus21002
Guest
|
| Posted:
Fri Oct 28, 2005 12:35 am Post subject:
Re: 3 phase motor? |
|
|
On Thu, 27 Oct 2005 16:21:42 +0200, Ken O <lerameur@ya.com> wrote:
| Quote: | Hello,
Just like to know if it was possible to convert from 1 phase to three phase
AC ?
|
Yes, it is called a phase converter. Converts single phase to three
phase.
There are two kinds, electronic converters (which often are just there
to help start 3 phase motors and then switch them to single phase AC),
and rotary phase converters (RPC).
Rotary phase converters rely on the fact that
1) a 3 phase motor, if spun up, would continue spinning on single
phase only
2) Such a motor, while spinning, generates magnetic fields that
produce phase shifted voltage in the third leg.
I built a homemade RPC for just $45 in used parts, see the story,
reference information etc
http://igor.chudov.com/projects/Phase-Converter/
| Quote: | See I have a motor that will run on 3 phase, and at hone I have only 1
phase. I would like to build a unit that will take three 1 phase, retard the
third and last phase 120 degree so it can turn my engine. Any comment will
be greatly appreciate
|
It's really a one evening project once you have all the parts.
You would later find that buying all necessary wires and cables,
disconnects, etc to both supply power to the RPC, as well as to
deliver power to 3 phase devices, would be much more costly and time
consuming. But, proper wiring is a must! (and you would do the same
with commercial phase converters that you buy)
I use my phase converter a lot. Having a decent RPC allows you to buy
high quality, used industrial machinery for very low prices compared
to single phase stuff.
For example, my 3 phase TIG welder cost me only $9.99:
http://igor.chudov.com/projects/Welding/00-Hobart-CyberTig-Welder/
i
|
|
| Back to top |
|
|
Roger Hamlett
Guest
|
| Posted:
Fri Oct 28, 2005 12:35 am Post subject:
Re: 3 phase motor? |
|
|
"Ken O" <lerameur@ya.com> wrote in message
news:SEa8f.10806$Nj3.1002173@news20.bellglobal.com...
| Quote: | Hello,
Just like to know if it was possible to convert from 1 phase to three
phase AC ?
See I have a motor that will run on 3 phase, and at hone I have only 1
phase. I would like to build a unit that will take three 1 phase, retard
the third and last phase 120 degree so it can turn my engine. Any
comment will be greatly appreciate
thank you
Ken O
Buy one. |
It is possible, but doing it with good power factor correction, and
safely, is hard work, and will involve a lot of time. Even on commercial
units, there are two basically different types. The type needed will
depend on the actual layout of the motor.
The simpler/cheaper type, does it in solid state, and is dependant on a
motor that has star windings, not delta windings. The second form includes
transformer coupling, or a rotary converter, and is more expensive. Units
are made by companies like LG, Toshiba, Westinghouse, Hyundai etc.. Look
at:
http://www.3-phaseconverter.com/Inverter.html
Generally the better units, also offer you the option of operating the
motor at different speeds, and ramping acceleration/deceleration as well,
giving more flexibility, and less droop on the incoming supply when
starting. You could not even buy the parts to build such a unit, for the
prices they sell for, especially on places like Ebay.
Best Wishes |
|
| Back to top |
|
|
Ignoramus21002
Guest
|
| Posted:
Fri Oct 28, 2005 12:35 am Post subject:
Re: 3 phase motor? |
|
|
On Thu, 27 Oct 2005 20:38:12 GMT, Roger Hamlett <rogerspamignored@ttelmah.demon.co.uk> wrote:
| Quote: | It is possible, but doing it with good power factor correction, and
safely, is hard work, and will involve a lot of time. Even on commercial
units, there are two basically different types. The type needed will
depend on the actual layout of the motor.
|
It is not at all difficult, I did it basically in two evenings (I was
interrupted by family and had to ask questions on newsgroup).
| Quote: | The simpler/cheaper type, does it in solid state, and is dependant on a
motor that has star windings, not delta windings. The second form includes
transformer coupling, or a rotary converter, and is more expensive. Units
are made by companies like LG, Toshiba, Westinghouse, Hyundai etc.. Look
at:
http://www.3-phaseconverter.com/Inverter.html
Generally the better units, also offer you the option of operating the
motor at different speeds, and ramping acceleration/deceleration as well,
giving more flexibility, and less droop on the incoming supply when
starting. You could not even buy the parts to build such a unit, for the
prices they sell for, especially on places like Ebay.
|
My 10 HP rotary phase converter cost me $45 in parts. Granted, I am
pretty good at getting stuff cheaply. For a more regular person, who
would buy a used 3 phase motor for about $5 per HP at a local scrap
company, and caps on ebay, the cost would be about $80 or so, plus
electric wiring costs -- all those cables, circuit breakers etc, that
you have to buy regardless of whether your RPC is homemade or store
bought.
http://igor.chudov.com/projects/Phase-Converter/
This is a perfect home project where not many things can go wrong that
are not easily corrected.
i |
|
| Back to top |
|
|
Don Lancaster
Guest
|
| Posted:
Fri Oct 28, 2005 12:35 am Post subject:
Re: 3 phase motor? |
|
|
Ken O wrote:
| Quote: | Hello,
Just like to know if it was possible to convert from 1 phase to three phase
AC ?
See I have a motor that will run on 3 phase, and at hone I have only 1
phase. I would like to build a unit that will take three 1 phase, retard the
third and last phase 120 degree so it can turn my engine. Any comment will
be greatly appreciate
thank you
Ken O
|
These days, it is simplest and best to buy a three phase variable
frequency drive that is single phase powered.
A typical three horsepower 220 volt unit now only costs around $300 and
is ridiculously smaller and lighter than building up your own.
We have smaller units in stock at bargain prices.
http://cgi.ebay.com/AB-160-SSC-Speed-Controller-3-ph-converter_W0QQitemZ2594231112QQcategoryZ4660QQssPageNameZWDVWQQrdZ1QQcmdZViewItem
--
Many thanks,
Don Lancaster voice phone: (928)428-4073
Synergetics 3860 West First Street Box 809 Thatcher, AZ 85552
rss: http://www.tinaja.com/whtnu.xml email: don@tinaja.com
Please visit my GURU's LAIR web site at http://www.tinaja.com |
|
| Back to top |
|
|
Ignoramus21002
Guest
|
| Posted:
Fri Oct 28, 2005 12:35 am Post subject:
Re: 3 phase motor? |
|
|
On Thu, 27 Oct 2005 17:27:25 +0200, Ken O <lerameur@ya.com> wrote:
| Quote: |
"Ignoramus21002" <ignoramus21002@NOSPAM.21002.invalid> wrote in message
news:56b8f.3816$Ty.2609@fe79.usenetserver.com...
On Thu, 27 Oct 2005 20:38:12 GMT, Roger Hamlett
rogerspamignored@ttelmah.demon.co.uk> wrote:
It is possible, but doing it with good power factor correction, and
safely, is hard work, and will involve a lot of time. Even on commercial
units, there are two basically different types. The type needed will
depend on the actual layout of the motor.
It is not at all difficult, I did it basically in two evenings (I was
interrupted by family and had to ask questions on newsgroup).
The simpler/cheaper type, does it in solid state, and is dependant on a
motor that has star windings, not delta windings. The second form
includes
transformer coupling, or a rotary converter, and is more expensive. Units
are made by companies like LG, Toshiba, Westinghouse, Hyundai etc.. Look
at:
http://www.3-phaseconverter.com/Inverter.html
Generally the better units, also offer you the option of operating the
motor at different speeds, and ramping acceleration/deceleration as well,
giving more flexibility, and less droop on the incoming supply when
starting. You could not even buy the parts to build such a unit, for the
prices they sell for, especially on places like Ebay.
My 10 HP rotary phase converter cost me $45 in parts. Granted, I am
pretty good at getting stuff cheaply. For a more regular person, who
would buy a used 3 phase motor for about $5 per HP at a local scrap
company, and caps on ebay, the cost would be about $80 or so, plus
electric wiring costs -- all those cables, circuit breakers etc, that
you have to buy regardless of whether your RPC is homemade or store
bought.
http://igor.chudov.com/projects/Phase-Converter/
This is a perfect home project where not many things can go wrong that
are not easily corrected.
Thanks for the tips. I will look into that.
I also omitted that I need 550 volts to tun this baby.
|
that makes some difference:)
What is the baby actually -- what is the device that you need to
power, and what power source do you have available at your present
location?
i |
|
| Back to top |
|
|
Spehro Pefhany
Guest
|
| Posted:
Fri Oct 28, 2005 12:35 am Post subject:
Re: 3 phase motor? |
|
|
On Thu, 27 Oct 2005 16:21:42 +0200, the renowned "Ken O"
<lerameur@ya.com> wrote:
| Quote: | Hello,
Just like to know if it was possible to convert from 1 phase to three phase
AC ?
See I have a motor that will run on 3 phase, and at hone I have only 1
phase. I would like to build a unit that will take three 1 phase, retard the
third and last phase 120 degree so it can turn my engine. Any comment will
be greatly appreciate
thank you
Ken O
|
ig has already given you one answer. You might try a google search in
rec.crafts.metalworking-- this question often comes up for motors of a
few HP on "old iron" machines that people want to run in their
basement (or garage for those who must do without).
There are basically three approaches--
Rotary phase converter- an idler motor, often with some added
capacitors, that essentially operates powered off of one phase and
generates the other two. You get most of the available torque,
especially with the proper capacitors. A simple electrical circuit or
a small starting motor is used to get the idler spinning. Line
frequency only. This is a good approach if you don't mind lugging
around some scrap iron as you can often get the 3-phase idler motor
basically for free (it has to be rather larger in HP than the largest
motor you wish to run). I bought a 10HP/240V one for $150 delivered,
but that was for a brand new Baldor- a bit of a bargain because it was
nameplated at 50Hz.
Static phase converter- uses phase shifting (passive components) to
create the other phases. Gives only partial torque. Line frequency
only. Not really recommended.
VFD - the incoming single phase power is rectified and filtered, and
three-phase power is generated from the DC rail using three
half-bridges. You get to set the frequency over a range so you can
vary the speed of your motor, plus a nice digital display etc. It's a
bit harder on the motor insulation than just running it from the line,
but well-designed motors should be okay.
Best regards,
Spehro Pefhany
--
"it's the network..." "The Journey is the reward"
speff@interlog.com Info for manufacturers: http://www.trexon.com
Embedded software/hardware/analog Info for designers: http://www.speff.com |
|
| Back to top |
|
|
Dave
Guest
|
| Posted:
Fri Oct 28, 2005 12:35 am Post subject:
Re: 3 phase motor? |
|
|
Ken O wrote:
| Quote: | Hello,
Just like to know if it was possible to convert from 1 phase to three phase
AC ?
|
Yes, but most converters have not tended to be very good. I've never
built one, but have heard a lot of problems exist.
You have 4 options
1) Investigate if its possible to get a 3 phase supply to your house.
99% of houses in the UK have single phase, but mine has 3 phase, which
was installed due to the power requirments of "economy 7" electrical
storage heaters. There is no extra standing charge for having a 3 phase
meter. You may well find it can be installed for zero cost. Admittidly
its not likely, but I would investigate.
I don't have any 3 phase consumer unit, but if you want to run 3 phase
kit, you will find those are not cheap like normal domestic ones.
2) Build/buy a converter.
3) Replace the motor with single phase. This is often the most
economical solution. If the motor is too big to run from single phase,
then I suggest you take route 1 and get a real 3 phase supply. |
|
| Back to top |
|
|
Ignoramus21002
Guest
|
| Posted:
Fri Oct 28, 2005 12:35 am Post subject:
Re: 3 phase motor? |
|
|
On Thu, 27 Oct 2005 23:44:22 +0100, Dave <nospam@nowhere.com> wrote:
| Quote: | Ken O wrote:
Hello,
Just like to know if it was possible to convert from 1 phase to three phase
AC ?
Yes, but most converters have not tended to be very good. I've never
built one, but have heard a lot of problems exist.
|
Well, I have built one, and it works just fine, within the limits of
its rated power.
| Quote: | 3) Replace the motor with single phase. This is often the most
economical solution. If the motor is too big to run from single phase,
then I suggest you take route 1 and get a real 3 phase supply.
|
Building a 10 HP phase converter is cheaper than buying a 5 HP single
phase motor. I built the former and resold the latter, that's how Iknow.
i |
|
| Back to top |
|
|
Roger Hamlett
Guest
|
| Posted:
Fri Oct 28, 2005 1:52 pm Post subject:
Re: 3 phase motor? |
|
|
"Ignoramus21002" <ignoramus21002@NOSPAM.21002.invalid> wrote in message
news:56b8f.3816$Ty.2609@fe79.usenetserver.com...
| Quote: | On Thu, 27 Oct 2005 20:38:12 GMT, Roger Hamlett
rogerspamignored@ttelmah.demon.co.uk> wrote:
It is possible, but doing it with good power factor correction, and
safely, is hard work, and will involve a lot of time. Even on
commercial
units, there are two basically different types. The type needed will
depend on the actual layout of the motor.
It is not at all difficult, I did it basically in two evenings (I was
interrupted by family and had to ask questions on newsgroup).
Yes. Yours is a rotary converter, which is really easier to do 'safely', |
than a solid state unit. For most likely motors, depending on the
competence of the poster, this could well be an 'option'.
| Quote: | The simpler/cheaper type, does it in solid state, and is dependant on a
motor that has star windings, not delta windings. The second form
includes
transformer coupling, or a rotary converter, and is more expensive.
Units
are made by companies like LG, Toshiba, Westinghouse, Hyundai etc..
Look
at:
http://www.3-phaseconverter.com/Inverter.html
Generally the better units, also offer you the option of operating the
motor at different speeds, and ramping acceleration/deceleration as
well,
giving more flexibility, and less droop on the incoming supply when
starting. You could not even buy the parts to build such a unit, for
the
prices they sell for, especially on places like Ebay.
My 10 HP rotary phase converter cost me $45 in parts. Granted, I am
pretty good at getting stuff cheaply. For a more regular person, who
would buy a used 3 phase motor for about $5 per HP at a local scrap
company, and caps on ebay, the cost would be about $80 or so, plus
electric wiring costs -- all those cables, circuit breakers etc, that
you have to buy regardless of whether your RPC is homemade or store
bought.
http://igor.chudov.com/projects/Phase-Converter/
This is a perfect home project where not many things can go wrong that
are not easily corrected.
Your buying skills are obviously pretty good. :-) |
Best Wishes |
|
| Back to top |
|
|
Ignoramus6607
Guest
|
| Posted:
Fri Oct 28, 2005 4:21 pm Post subject:
Re: 3 phase motor? |
|
|
On Fri, 28 Oct 2005 08:52:55 GMT, Roger Hamlett <rogerspamignored@ttelmah.demon.co.uk> wrote:
| Quote: |
"Ignoramus21002" <ignoramus21002@NOSPAM.21002.invalid> wrote in message
news:56b8f.3816$Ty.2609@fe79.usenetserver.com...
On Thu, 27 Oct 2005 20:38:12 GMT, Roger Hamlett
rogerspamignored@ttelmah.demon.co.uk> wrote:
It is possible, but doing it with good power factor correction, and
safely, is hard work, and will involve a lot of time. Even on
commercial
units, there are two basically different types. The type needed will
depend on the actual layout of the motor.
It is not at all difficult, I did it basically in two evenings (I was
interrupted by family and had to ask questions on newsgroup).
Yes. Yours is a rotary converter, which is really easier to do 'safely',
than a solid state unit. For most likely motors, depending on the
competence of the poster, this could well be an 'option'.
|
And note that it produces an almost perfect sinewave in the third leg
(perfection dependent mostly on current draw vs. idler horsepower),
and not some weird waveform.
| Quote: | The simpler/cheaper type, does it in solid state, and is dependant on a
motor that has star windings, not delta windings. The second form
includes
transformer coupling, or a rotary converter, and is more expensive.
Units
are made by companies like LG, Toshiba, Westinghouse, Hyundai etc..
Look
at:
http://www.3-phaseconverter.com/Inverter.html
Generally the better units, also offer you the option of operating the
motor at different speeds, and ramping acceleration/deceleration as
well,
giving more flexibility, and less droop on the incoming supply when
starting. You could not even buy the parts to build such a unit, for
the
prices they sell for, especially on places like Ebay.
My 10 HP rotary phase converter cost me $45 in parts. Granted, I am
pretty good at getting stuff cheaply. For a more regular person, who
would buy a used 3 phase motor for about $5 per HP at a local scrap
company, and caps on ebay, the cost would be about $80 or so, plus
electric wiring costs -- all those cables, circuit breakers etc, that
you have to buy regardless of whether your RPC is homemade or store
bought.
http://igor.chudov.com/projects/Phase-Converter/
This is a perfect home project where not many things can go wrong that
are not easily corrected.
Your buying skills are obviously pretty good. :-)
|
Even with not so good buying skills, a homemade RPC is an obvious
winner.
i |
|
| Back to top |
|
|
Rich Grise
Guest
|
| Posted:
Fri Oct 28, 2005 10:37 pm Post subject:
Re: 3 phase motor? |
|
|
On Thu, 27 Oct 2005 17:27:25 +0200, Ken O wrote:
| Quote: | "Ignoramus21002" <ignoramus21002@NOSPAM.21002.invalid> wrote in message
On Thu, 27 Oct 2005 20:38:12 GMT, Roger Hamlett
It is possible, but doing it with good power factor correction, and
safely, is hard work, and will involve a lot of time. Even on commercial
units, there are two basically different types. The type needed will
depend on the actual layout of the motor.
....
at:
http://www.3-phaseconverter.com/Inverter.html
....
http://igor.chudov.com/projects/Phase-Converter/
This is a perfect home project where not many things can go wrong that
are not easily corrected.
Thanks for the tips. I will look into that.
I also omitted that I need 550 volts to tun this baby.
|
It might be cheaper in the long run to have the power company run
a new 3-phase feed. :-)
Cheers!
Rich |
|
| Back to top |
|
|
Jasen Betts
Guest
|
| Posted:
Sat Oct 29, 2005 2:25 pm Post subject:
Re: 3 phase motor? |
|
|
["Followup-To:" header set to sci.electronics.design.]
On 2005-10-27, Ken O <lerameur@ya.com> wrote:
| Quote: | Hello,
Just like to know if it was possible to convert from 1 phase to three phase
AC ?
|
call the electricty supply company and say "I'd like to convert to 3 phase
elecricity" have your cheque book handy.
| Quote: | See I have a motor that will run on 3 phase, and at hone I have only 1
phase. I would like to build a unit that will take three 1 phase, retard the
third and last phase 120 degree so it can turn my engine. Any comment will
be greatly appreciate
|
It'd probably be easier to replace the motor with a single phase motor.
Bye.
Jasen |
|
| Back to top |
|
|
John Fields
Guest
|
| Posted:
Sat Oct 29, 2005 4:35 pm Post subject:
Re: 3 phase motor? |
|
|
On Thu, 27 Oct 2005 16:21:42 +0200, "Ken O" <lerameur@ya.com> wrote:
| Quote: | Hello,
Just like to know if it was possible to convert from 1 phase to three phase
AC ?
See I have a motor that will run on 3 phase, and at hone I have only 1
phase. I would like to build a unit that will take three 1 phase, retard the
third and last phase 120 degree so it can turn my engine. Any comment will
be greatly appreciate
|
---
http://www.google.com/search?sourceid=navclient&ie=UTF-8&rls=GGLD,GGLD:2004-42,GGLD:en&q=3%2Dphase+converter
--
John Fields
Professional Circuit Designer |
|
| Back to top |
|
|
|
|
|
|
FAQ
Memberlist
Register
Profile
Log in to check your private messages
Log in