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Sparks fly from my finger
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It is as easy as this: buy a proper sized single phase input inverter for the motor you have, remove the starter from the control cabinet, put the inverter in its place, put the wire that went to the forward coil on the forward input on the inverter, put the wire that went to the reverse coil to the reverse input of the inverter, program inverter.

If it is a small enough inverter you might even be able to power it with 120 volt.

What is the horsepower, amps and rpm of the motor?
 

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It is as easy as this: buy a proper sized single phase input inverter for the motor you have, remove the starter from the control cabinet, put the inverter in its place, put the wire that went to the forward coil on the forward input on the inverter, put the wire that went to the reverse coil to the reverse input of the inverter, program inverter.
What about the OL's ?

Buzzkill, Is there schematic you can post ?
 

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I had to do this in a wood shop and I just used a phase converter
 
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http://www.kbelectronics.com/Variable_Speed_AC_Drives_Inverters/AC_Drives_Chassis.html

The small chassis mount might just fit in place of the contactor. If its an IEC contactor it most likely will not fit and you will need to make some room or buy the enclosure model and mount it to the outside of the existing enclosure.

Note: The VFD can only operate the motor. You will need to control the VFD. So get the schematic from the web site and make your drawing to work from.
 

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Thanks for the help fellow sparks!
Any the decision yet ?

My only concern with using a VFD would be that dreaded phone call down the road that it failed ! I don't know the reliability for the application vs using a phase convertor .

3 HP convertor for $345.00
3 HP Single phase input drive $368.
 

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Discussion Starter #34 (Edited)
Any the decision yet ?

My only concern with using a VFD would be that dreaded phone call down the road that it failed ! I don't know the reliability for the application vs using a phase convertor .

3 HP convertor for $345.00
3 HP Single phase input drive $368.
Sorry I missed this Dronai.
I'm getting a phase inverter; $345 for a 3HP model and $95 shipping. Mount it and the motor by the panel and run some conduit 30 feet to the showroom so he can show off his new shredder to customers. I haven't done the estimate yet, doing that over the week end. Prob a $1650ish job.
 

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Also if he disconnects the forward and reverse starters to use for his VFD, there may be aux contacts that close when the starters close, that need to work. Some controls are also wired into the control circuit for safety devices like the access doors. That's why I said to look at the schematic first.
 

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Sparks fly from my finger
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If you use a static phase converter the motor gets de rated by 1/3. So basically a 3hp motor becomes a 2hp motor. This may be a problem if the machine sees a heavy load. Vfd's are pretty cheap now days and most of the ones I've used, you can input single phase or three phase. Overloads are built into the vfd. Just program and go. I've done this on several occasions. Works very well.


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