VFD On single phase motor

M

MattiBoi

Joined
Jan 21, 2020
Messages
1
Hi Guys,

My name is Matt im from uk and im new on the forum. Im also very fresh to knife making.
I have been using a belt grinder with an 2.2 kw 12 amp single phase motor. Im looking to buy some cheap chinese vfd up 100 gbp. But for the love of god i can not seem to find one . Im looking for 1ph in and 1 ph out vfd. Most of them specify 1ph to 3 ph or they call them universal vfd. Ill be forever greatful for any help tips and tricks.

P.s My apologies to mod if its wrong section to post
 
If you have a single-phase industrial motor, with a starting capacitor, it will not work.

Single-phase VFDs are unusual and are mainly used with fans, which need much less torque at low speeds. They are not at all suitable for constant-torque applications, which are basically anything “we” are likely to want to do with a VFD.

To run variable-speed realistically, you’ll need a single-phase in, 3-phase out VFD and a 3-Phase motor.

The nameplate details on your motor should include the frame size, possibly as part of the model number. In most cases, the motor will be one of the standard frame sizes and you can swap it out for a 3-phase one with no problem.

Most European motors are to IEC frame size standards and you’ll be looking for a number (most likely 80, 90 or 100) and S, M or L for short, medium or long.
 
I do t know if I have ever seen a single phase out VFD. I have seen PWM for single phase but that not high torque allocations.

yeah if you want VFD you need a 3 phase motor. Problem with single phase motors is usually thy are capacitor start which means there is a mechanical switch inside that switches them on and then off when the proper rpm is reached. If you drop the rpm it will engage the capacitor(s) and over heat if it can’t speed up to disengage the caps.
 
Single phase VFDs will usually work with Permanent Split Capacitor motors or Shaded Pole motors, neither of which will have the centrifugal-switched start winding. As said above, applications are somewhat limited and there seems very little chance that using one will offer an easier way of doing anything related to knife making, except perhaps running a forge blower.
 
For vfd, you need three phase, or DC. You might force a single phase motor to work, but it will burn out.
 
As amusing aside.
If we think about it, those are actually two phase motors.
Its ‘second phase’ created within the motor itself. Either by capacitance phaseshift or magnetic phaseshift respetively.
Single phase VFDs will usually work with Permanent Split Capacitor motors or Shaded Pole motors,
Click to expand...
 
You must log in or register to reply here.
Back
Top