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Rotary vs Static

Rotary vs Static

Rotary vs Static

(OP)
I came across a 3 phase air compressor really cheap. Only 1 problem. I was curious about the pros and cons of static vs rotary converters. I know that static will reduce hp by about 1/3. Rotary converters however are 3 fold the price. I am not interested in wiring a ghost phase for fear of ruining my motor. A 10 hp in single phase is just as expensive as a rotary converter. There seems to be no economical way around this delimma. Please advise.

RE: Rotary vs Static

I would stay with rotary..simple, rugged and little maintenance copared to electronic stuff which have short useful life and availabilty of parts stops usually after 5-7 years.

Also try persuading utiltiy co. to provide you a 3 phase service.

RE: Rotary vs Static

What rbulsara said.
Stay with what can be fixed easily with simple parts and meters.

RE: Rotary vs Static

Suggestion: The power electronics is constantly progressing. It will be around for time to come. I worked on electric rail cars that were overhauled, with SCR controls at that time. The electronics did a good job and parts were available.
The computer technology works, and it is fairly reliable. My old retired computer from early 90ties still works and runs the old software pretty fast. It is also on and off pretty quick in comparison to current windows, e.g. XP Pro.
I would look at some static converters offered on web, e.g.
http://www.thomasregister.com
and type Converters: Phase under Product or Service, which will return 62 companies to approach to

RE: Rotary vs Static

I consider all alternatives viable but should be chosen based on site conditions and how the equipment is to be used.

Recently we helped one of our small machining vendors with exactly same problem.  Purchased machine with 10 hp 3 phase motor but they only have 1 phase.  Best method that time was VFD.  Decision was based on ease of purchase and installation, requirements of the machine, and space available to mount equipment.

In your case however a single phase motor might be better as long as the cost of operation is not a big deal.  If you start and run a single phase motor heavily 24/7 then not a good idea.

PUMPDESIGNER

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