3 phase

[Fencing]

Any one recommend a good single to 3 phase converter. running a 4hp motor

[agrimog]

depends on the use, speed control required = VFD, newton tesla, check there site on ebay, no speed control, a plain static convertor, same source, both types are expensive when your talking 4hp(3Kw)

[twmarriott]

we had a transwave it was very good until we out grew it.

[eldon]

I have a digiphase that powers a lathe and a metal saw. Think mine max's about 3hp but they do bigger ones. The company link is here and I have no connection other than being a satisfied customer;

 

Digi-Phase

 

They are very helpful and will freely advise.

[flames]

'drives direct', see on ebay, an inverter is by far the best way to go!

[eldon]

Have to disagree - an inverter is not the best option!

A rotary convertor is by far a more time proven long lived repairable item.

 

With an inverter you get the bonus of variable speed control. This sounds great but unfortunately this has an inverse connection to the torque value in an ideal world; high speed high torque, low speed low torque. What good is that?

Edited June 21, 2014 by eldon

[mixedangased]

Any one recommend a good single to 3 phase converter. running a 4hp motor

 

swap the motor for single phase might be cheaper.

[flames]

Have to disagree - an inverter is not the best option!

A rotary convertor is by far a more time proven long lived repairable item.

 

With an inverter you get the bonus of variable speed control. This sounds great but unfortunately this has an inverse connection to the torque value in an ideal world; high speed high torque, low speed low torque. What good is that?

 

It is true that a rotary phase converter might be more servicable, but they are very costly to run, as its convertor motor has to run continuously which wastes energy, I would imagine the the energy cost would go a good way to paying for a replacement inverter over say a 10 year life span.

 

Having said that I have been running a 4kW TECO inverter, (stand-by power 20W) for over 8 years without fault, and it has stopped me burning out my machines motors several times (wireless overload protection). Also don't overlook an inverter is very compact (mine's about the size of a toaster), and typically have a whole host of other advantageous functions too.

 

Sorry of I've miss understood your statement about "inverse connection to the torque value" but I think what you've said is wrong, - (simplistically) a VFC induction motor will give you constant torque up to the rated speed, and then constant power above the rated speed. This is what you would want in most mechanical applications.

 

Some good examples here:

Drives Direct - Digital Phase Converters - Home Page

 

-and google...