Phase Converter

[halcyon0]

Hello All.

I picked up a Stenhoj Hydraulic Press that is a 3 phase unit.
I need to get a phase converter for it. I have heard that a static one will work just fine for it, but then I have also heard that a static will put strain on the motor and could cause the motor to fail.

Should I be looking at a rotary phase converter? Which are some of the better quality brands? I have see Temco (PowerWave) for a decent price, but have heard that the American Rotary units are better? Anyone have either?

Cheers!

 

[2mJps]

You can build one easy. What is the hp of pump? Can you replace motor/ pump?

 

[halcyon0]

I believe that it is a 2HP pump. I can't really replace the motor.

I would rather purchase a ready made unit than source parts and build one. The Power Wave is $295 and the American Roatary is approx $410. I am not sure that I could source quality parts for much less than that.

 

[930dreamer]

Go with a rotary phase converter, I can't help with a brand. Post some pics when you receive it.

 

[Ascinder]

The static converter usually pumps out less HP than a rotary. You can usually find pretty cheap 3 phase motors on craigslist. With a static converter, they can be wired up into a rotary converter. The motor you use for the rotary must be larger HP than the one you're going to run. Go to phase-a-matics website under static converter and view the brochure- it lays out how it all works.

 

[Tscott]

I'm no expert, so take it for what it is, but as long as the phase converter puts out a true sine wave with a frequency of 60Hz then it shouldn't matter what kind it is (i.e. Static or rotary). The motor you are trying to run doesn't know what type of converter is running it, all it knows is the power quality it receives.

I've never worked with one of these, but my guess would be that the cheaper the static unit, the worse the shape of the sign wave coming out of it. I imagine a square wave into an induction motor would cause some undue stress and possibly overheating.

Tom

 

[lametec]

A static phase converter is just a capacitor. It simply "shifts" the power from one phase onto the 3rd phase. Unfortunately, it doesn't do such a good job of it, and as such, you're stuck with only about 2/3 the power output from the 3-phase motor.

A static converter is not good choice for a hydraulic pump imho. The motor is most likely sized to where it needs all of the 2hp to create the design pressure.

 

[halcyon0]

Thanks for all the input guys!
I decided to go with the American Rotary 7.5HP rotary phase converter.
That should do the trick I hope.

 

[APEowner]

I have an American Rotary 5hp and I'm very happy with it. Quality construction, good documentation, excellent support and I hooked it up, it worked and I haven't had to do anything with it since.

 

[halcyon0]

That's what I hear and why I decided to go with them.
I should get in in a few days. Can't wait to wire it up and get my press going.

 

[padronanniversary]

how loud are the phase converters ?

 

[Alchymist]

Should have looked into the VFDs. Go here and poke in your requirements:

http://www.wolfautomation.com/Configure3.aspx?ProductID=23167&x=29&y=4

$225 for a 230v single phase input with 2 hp 3 phase output......Just because the frequency (thus speed) can be varied, doesn't mean you cant set it at one fixed speed.

 

[ZTFab]

You won't be disappointed with the American Rotary unit.

I've had a 20hp RPC from them for 3 years. The quality is excellent and the customer service is even better.

 

[Cookannapurna]

I would look into a VFD for anything 3 hp or smaller.