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Posted By: Raymfl 3 phase inverter/ frequency drive - 09/30/07 02:34 PM
Need a 3 phase converter for a 1-1/2hp motor. Was considering using a capacitor or rotary converter when someone here suggested a inverter fequency drive. Checked some on the net and the price looks real good. I don't have any experience with these an would like some input.

Ray
Posted By: JValdes Re: 3 phase inverter/ frequency drive - 09/30/07 04:37 PM
Ray, Yes the inverter is your best best. Economical and reliable. You will need 240 volt single phase. They do make 120 volt inverters with 3 phase output, but not for motors over 1hp. Check (www.KB_Controls.com) for 120 volt.
You will most likely not to have to derate. Most inverter manufacturer's require no derate in the smaller HP ranges.
You also eliminate stop/start and overload relay.
Your best price may be at www.automationdirect.com.

If your situation is just to run the motor at full speed then you will only have to program for the quick start.
Basic installation and neccessary program settings.

Make sure you connect it for single phase. Some require a jumper for the spare terminal. Read the manual!
Posted By: wire_twister Re: 3 phase inverter/ frequency drive - 09/30/07 06:22 PM
I have installed several units from automation direct, they are good units, come with good instructions and are reasonably compact. Programing is a breeze if you read the manual, best to go thru and decide on all the parameters first, then get into programing. The drives I installed are the GS2 series, I liked them the customer loves them.
Posted By: Raymfl Re: 3 phase inverter/ frequency drive - 09/30/07 07:02 PM
Are the ones on automationdirect Hitachi? Can't beat the application and price with anything else for small motors. They are similar in operation to my PWM speed controllers I use for my electric rc airplane motors.

Thanks for the info. Will definately order one.

Ray
Posted By: wire_twister Re: 3 phase inverter/ frequency drive - 09/30/07 10:31 PM
not shure who makes them, just have automation direct on them.
Posted By: JValdes Re: 3 phase inverter/ frequency drive - 10/01/07 03:03 PM
Automation direct name brands the low cost drive so I am not sure who makes them either.
I can usually tell by looking at one, which I will do today.

Great prices aren't they. For your application would it matter that much who built the control?

All of them are similar, with the exception of programming. Some are real easy and some are so detailed (AB) youwould need help.

Yes, they are "pulse width modulation" based
Posted By: JValdes Re: 3 phase inverter/ frequency drive - 10/01/07 03:23 PM
Just checked the web site. Still not sure who built it.
You will have to go to the 2HP. 1.5 not available.


Is your motor new? Be careful if you have an older motor. It may not last long with the drive.
The new motors "most" have special magnet wire for inverter duty. They also have better bearings and sometimes insulated bearings.
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