[TheForge] 15Ton Press

[Ed Fasula]

Hi Steve,

I think it kinda cool that if I start out with an 1800 rpm 3hp motor and 
use the VFD to double the speed to 3600, the motor's output torque will 
meet or exceed a 5hp 3600 rpm motor to satisfy the demand of the pump.  (I 
only need 2.5hp to run at 1800 so 5hp will handle double the hp of the pump 
at 1800.)  The local motor repair place does it often.  I can get a 5hp VFD 
factory refurbished for the same price as a new 3hp VFD (about $360).  So 
I'll start with one of the 3hp motors I got and if that's not kosher for 
whatever reason I'll scrounge or buy a used 5hp for $80.

The other option would be to make a phase converter and run a 3hp motor I 
have.  Say $80 for the extra motor plus $70 for the phase converter 
electronics (I think - correct me if I'm wrong).  So I'm paying $210 for 
the ability to run the wood splitter and tune-in the speed of my press.  I 
also have thoughts about wiring a switch in that would allow me to use the 
VFD to run the power hammer motor.  I've always wanted to play with the rpm 
of that thing.

All in all, I don't know if it's wise or not, but it seems worth the 
experience and possible benefits.  If I don't have to do anything exotic 
with my cylinder porting I'm getting off pretty cheap on this press so the 
extra $210 doesn't make me whine to much.

Ed


>If you double the speed, you also double the HP required out of the motor. 
>I don't
>know if this is a wise idea.
>
>Steve
>
>Ed Fasula wrote:
>
> > Hi Steve,
> > I'm thinking that I'd like the variable speed so that I can double speed
> > the motor for splitting wood or if I want to go quicker.  Thanks tho.
> >
> > Ed


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