Static phase converters vs. vfd's

Given a choice between a static converter and a VFD... If I were not allowed to have a VFD, I'd convert my equipment back to single phase. Static converters product "dirty" power and virtually all modern motor manufacturers will not warranty the product if it fails while on static power. I just purchased 3 new Leeson 3Ph motors and all clearly state "Warranty VOID if used with Static Converters". They are at best 66% efficient and much of the loss is taken-up as heat in the motor because the "phases" are not 120[SUP]o[/SUP] apart and that causes the motor to fight against itself.


EDIT:

Rotary converters: They're pretty good -provided you like having another set of motors to maintain and a couple hundred pounds of additional stuff in your shop. At least they produce good power. They can be made cheaply -if you happen to know someone giving away a 2, 3, 5+ HP 3-phase motor.


VFD: They work perfectly, cost $125-$150 bucks. Only downside is a little learning curve and reading their poorly translated user manuals. A friend of mine owns a food processing company and they must have 100-200 VFD in operation at any given moment. About once a year, one of them fails -usually due to external damage.


Ray
 
Last edited:
Ray C said:
Given a choice between a static converter and a VFD... If I were not allowed to have a VFD, I'd convert my equipment back to single phase. Static converters product "dirty" power and virtually all modern motor manufacturers will not warranty the product if it fails while on static power. I just purchased 3 new Leeson 3Ph motors and all clearly state "Warranty VOID if used with Static Converters". They are at best 66% efficient and much of the loss is taken-up as heat in the motor because the "phases" are not 120[SUP]o[/SUP] apart and that causes the motor to fight against itself.


Ray
Click to expand...

Hello, totally agree,

i stupidly left swapping the motor out for a single phase of my list.:whistle:

whoops.

Stuart
 
I have used VFD and rotary converter (only last week, found one cheap).

I was perfectly happy with VFD on multiple 3/4hp machines, swapping the connection via TwistLock connectors. FANTASTIC to be able to dial the RPM!

I only got the rotary converter to run my horizontal Hardinge TM mill table powerfeed while using my VFD to cut with Rusnok vertical head..

VFD is quieter than my rotary as well I guess. Used Kay Phasemaster 5hp unit.


Bernie
 
Last edited:
I ran a static converter before I got the rotary last year. It worked fine. When running my lathe, I would turn on the mill, letting it function as an idler/rotary converter. I now have a 7.5 hp rotary converter. I hate the continuous whine and it draws a lot of power, even when the machines are off. Seriously thinking about going back to the static.
 
You must log in or register to reply here.
Back
Top