Grinder Motor and VFD

[Big Smitty]

I am close to buying a KMG and need some direction on the motor. Here are my set up requirements:

110V power supply
2 HP motor
Variable speed

I have access to motors from a local shop that rebuilds and sells them and also has new motors to buy. I do not have much experience in setting up motors, so I need some help. I would like input from the experts here prior to talking to the guys at the motor shop so I have an idea of what I need.

I want to know how to get the best set up from a cost and performance standpoint. Should I do an AC or DC motor and what do I need to control the set up.

 

[Jack O'Neill]

the motor shop that set me up years ago ( I knew them well ) .Did so with a DC motor 1 1/2 hp . But that was 15 yrs. ago , things change .

 

[Big Smitty]

Yep from the reading I have done I thought a DC motor might be the way to go. I just don't know the terms and exactly what I need.

 

[silver_pilate]

I'm in the process of researching this myself, but I don't know that you'll find many 2hp motors to run on 110. The max I've seen was 1.5hp on 110.

--nathan

 

[Steven Penner]

DC Motor controller info
Dc does have more torque than VFD on AC and perhaps 1.5 Hp is enough in DC


Stacy has experience with the DC motor/controller setup

KBPC-240D
will do 1.5 or 2 hp with proper setup

Needs 220V input

http://www.kbelectronics.com/catalog_nema_4x.htm

http://www.kbelectronics.com/data_sheets/kbpc_240d.pdf

http://www.kbelectronics.com/manuals/kbpc_240d.pdf

 

[pso]

When running at rated speed (100% rpm), an AC motor and a DC motor with the same rated hp and torque would have the same torque output. The torque avaliable from the DC motor will fall as the speed is reduced. With the AC motor, 100% of the rated torque is available over the whole speed range, from zero speed (0 rpm). This has to do with the physics of how the two types of motors work, not the make, model or place of manufacture.

Your 15A 110V service will give you up to 1650 Watts of power before you trip the breaker. This translates to 2.2 Electrical Horsepower. This is how much power you can have going into your AC or DC drive. The circuitry of the input stage of most small drives do not allow you to draw that much power, only about 80% of that. You then have to subtract the losses in the drive to account for the (in)efficiency of the drive. You then have to account for the (in)effeciency of the motor. You are then left with about 1.5 Mechanical Horsepower at your motor shaft.

Make the effort to wire your shop for 220V since it allows you to go to 3 Horsepower, and beyond. Of the AC drives (VFD's) that will run from single phase, very few are designed to run from 110V and they tend to be for motors less than 1 Horsepower. The 220V models probably won't blow up if connected to 110V. They will likely just display an "undervoltage" alarm and never allow you to start.

 

[medannyboyy]

Do the smart thing and get your motor from rob fink at beaumont metal works his v.s vfd motors and controlls are top of the line there ac and will last a lifetime and hes has everything you need there on his sight if your getting a kmg get the motor and controls from there too, you wont be dissapointed!