I may have access to a free lift but it is a 3 phase system. I have done enough research on phase converters to be dangerous, but not fully educated. Aside from the hp of the motor what information do I need about the lift to determine if a static or rotary converter is needed?
3 phase lift on single phase
- Thread starter Bojans
- Start date
Bojans,
In a nutshell:
Static phase converters are basically a box full of balancing capacitors. They are "static" because they don't require an idler motor. However, they only allow the motor to develop 2/3rds rated power. This can be problematic for a hydraulic pump installation. One static converter is required for each motor.
Rotary phase converters add a motor to the box of capacitors and provide true three-phase power. You can use the power they provide just as if it was a 3-phase service and run multiple machines. They can be simply a motor, or a motor with a box of balancing capacitors. Properly balanced, they can provide power just as good as what the power company supplies. They're easy to build and plans are readily available.
A third option is the relatively recent invention of "digital phase converters". These use electronic methods to convert 1-phase AC to DC, then chop it up into 3-phase AC. The power they supply is actually more stable than what comes in off the lines and like with a rotary converter, you can use it as a 3-phase service. They're expensive though.
Finally, there's the VFD. This is like a digital phase converter, but with the added ability to change the frequency of the output. However, these must DIRECTLY control the motor, with no switches between the VFD and the motor. This means the control circuitry of your lift would need to be re-wired to put the VFD in direct control instead of the motor starter.
I would build a simple rotary phase converter to operate that lift.
In a nutshell:
Static phase converters are basically a box full of balancing capacitors. They are "static" because they don't require an idler motor. However, they only allow the motor to develop 2/3rds rated power. This can be problematic for a hydraulic pump installation. One static converter is required for each motor.
Rotary phase converters add a motor to the box of capacitors and provide true three-phase power. You can use the power they provide just as if it was a 3-phase service and run multiple machines. They can be simply a motor, or a motor with a box of balancing capacitors. Properly balanced, they can provide power just as good as what the power company supplies. They're easy to build and plans are readily available.
A third option is the relatively recent invention of "digital phase converters". These use electronic methods to convert 1-phase AC to DC, then chop it up into 3-phase AC. The power they supply is actually more stable than what comes in off the lines and like with a rotary converter, you can use it as a 3-phase service. They're expensive though.
Finally, there's the VFD. This is like a digital phase converter, but with the added ability to change the frequency of the output. However, these must DIRECTLY control the motor, with no switches between the VFD and the motor. This means the control circuitry of your lift would need to be re-wired to put the VFD in direct control instead of the motor starter.
I would build a simple rotary phase converter to operate that lift.
Torque1st
MEMBER EMERITUS
Remember a hydraulic pump is considered a very hard start application for a rotary phase converter. You may need at least double the HP of the lift motor for your idler motor. Call several of the rotary converter companies and talk to their application engineers.
Gary S
Well-known member
I'd look into the possiblity of simply replacing the 3 phase motor with a similar single phase motor. If it is a standard motor frame, that might be the cheapest option.
Mohawk uses a 2.5 hp motor on their 10,000 lb lift
babzog
Well-known member
Likely the cheapest and almost certainly the simplest solution. If you're only looking at a 2.5 to 3hp motor, heck, you can get those cheap at TSC or cheaper at an auction (if you can wait a little while before installation).
BTW... free lift? Dude... you truly ****!
BillK
Well-known member
Bo,
You can buy the entire hydraulic unit for pretty cheap from Northern and othe places. Probably as much as you will spend on a good phase converter. http://www.northerntool.com/webapp/wcs/stores/servlet/category_6970_96+1502
You can buy the entire hydraulic unit for pretty cheap from Northern and othe places. Probably as much as you will spend on a good phase converter. http://www.northerntool.com/webapp/wcs/stores/servlet/category_6970_96+1502
Thanks for all the info guys.
The lifts are out of a shop my grandpa used to own, when he sold the building and my uncle heard it was going to be torn down he went and pulled the lifts prior to closing. He started with 3 of them and traded one for an alignment machine, is keeping the only single phase for himself (who can blame him) and I believe still has the third available. My new garage has a ceiling that ranges from 14-15'. I have had a number of people ask if I was going to put a lift in and those inquiries actually stopped me from doing it, worried friends and relatives would come over to change a ball joint and leave their car on the lift for a week. However knowing I have a potentially free lift at my disposal I am thinking I would be stupid not to take it. Still need to figure out if it will fit in the area I am hoping it to and get the specifics of the lift to understand the install, etc but the chance for a free lift probably only comes up once...
The lifts are out of a shop my grandpa used to own, when he sold the building and my uncle heard it was going to be torn down he went and pulled the lifts prior to closing. He started with 3 of them and traded one for an alignment machine, is keeping the only single phase for himself (who can blame him) and I believe still has the third available. My new garage has a ceiling that ranges from 14-15'. I have had a number of people ask if I was going to put a lift in and those inquiries actually stopped me from doing it, worried friends and relatives would come over to change a ball joint and leave their car on the lift for a week. However knowing I have a potentially free lift at my disposal I am thinking I would be stupid not to take it. Still need to figure out if it will fit in the area I am hoping it to and get the specifics of the lift to understand the install, etc but the chance for a free lift probably only comes up once...
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rsanter
Well-known member
either get a VFD or get a spare 3ph motor and add a static converter to it to make your own rotary phase converter
bob
bob
Get the lift. Find the motor frame number along with the other specs needed.
Order up or get a single phase motor and be done with it. It is a very simple swap.
For the cost of a converter and a slave motor. Its just not worth running that 3 phase motor unless you are going to have more 3 phase equipment.
Order up or get a single phase motor and be done with it. It is a very simple swap.
For the cost of a converter and a slave motor. Its just not worth running that 3 phase motor unless you are going to have more 3 phase equipment.
The problem with swapping to a single-phase motor is the motor design.
Many integrated hydraulic powerpacks use a special tang-drive motor, such as a BD56. They do not have a shaft, so not just any motor will work. You might get lucky, however. Surpluscenter.com does carry some hydraulic powerpack motors in single-phase here:
http://www.surpluscenter.com/item.asp?UID=2009072321355940&item=10-2105&catname=hydraulic
Many integrated hydraulic powerpacks use a special tang-drive motor, such as a BD56. They do not have a shaft, so not just any motor will work. You might get lucky, however. Surpluscenter.com does carry some hydraulic powerpack motors in single-phase here:
http://www.surpluscenter.com/item.asp?UID=2009072321355940&item=10-2105&catname=hydraulic
ultgar
Well-known member
I've sold quite a few Phase Perfect converters to people with 3-phase lifts. Unfortunately, the cheapest one is around $2800 delivered. SD
Aceman
Well-known member
You need to be aware that if you switch the motor to single from 3-phase often times it isn't just that simple. Motor starters may need to be replaced to handle the higher current required for the single phase motor, the wiring may be undersized as well.
If I get the lift I am thinking this may be my best option. May not be the cheapest way to do it, but probably the easiest.
http://www.northerntool.com/webapp/wcs/stores/servlet/product_6970_31157_31157
http://www.northerntool.com/webapp/wcs/stores/servlet/product_6970_31157_31157
kvom
Well-known member
You can get a 2HP VFD for less than $250.
Aaron Franck
Member
For years I was scared of 3 phase machines, because of the whole phase converter thing. BUT, a good electrician friend of mine showed me the way. A 3ph motor will run on 1ph, you just need to get it spinning before applying power. I built a simple stand using a 110v motor to spin a 3ph 208v 5hp that has 1ph 220v power running to it. The set up is direct drive and the 110v continues to spin(minus power to it) the whole time the 3ph motor is idleing. This set up has been powering my shop for 5+ yrs w/no problems. I built the whole thing w/parts I had around the shop. A decent electrician should be able to wire it all up.
Aaron
Aaron
stinkythings.com
Well-known member
In my opinion a VFD is the way to go. They are less expensive than buying a rotary Phase Converter. They are much more efficient. Go to www.dealerselectric.com .
I dealt with HAROLD there, he is very knowledgeable and will gladly answer all of your questions. They are also Ebay sellers with fantastic feedback.
I dealt with HAROLD there, he is very knowledgeable and will gladly answer all of your questions. They are also Ebay sellers with fantastic feedback.