You cannot get a VFD that outputs single phase as a general rule. So you will need to change your single phase motor for a 3 phase one.

As to which one to get, there simply isn't a realistic answer. They range from cheap and cheerful Chinese ones to very expensive industrial ones with all the bells and whistles. At least the latter have a comprehensive instruction manual.

To reverse the question, how much do you want to spend and what power 3 phase motor are you going to get? Answer that and people will give you a less wide range of answers!!

I tend to buy well known units second hand or even new.

Andrew.

It will give you the motor spindle speed.

I cant now remember which brand VFD they are but some have a multiplication factor that could display your spindle speed…but not if theres a gearbox with more than 1 ratio

It's certainly possible to get a single to single phase VFD, and as I understand it some models can have a scaling factor added to the display, though I'm not sure which ones.
A friend of mine has a 2"x72" belt grinder running off one as an experiment, though I don't know if that model has a programmable display.

It's also possible to run a single phase motor off some single to three phase VFDs, though not all will allow the correct programming. I don't know personally if any of those allow a display to be scaled.

This video is worth a look on how to run single phase motor off a specific ATO three phase output so it might be worth contacting ATO directly.
I guess you could try a single phase motor on it, and swap later to a three phase one, but it looks like they advise an inverter of double the normal rated capacity, so a higher initial expense.
You would have to check the prices yourself, as it may be more cost effective to get a smaller inverter and a new/second hand three phase motor.

,

Personally I'd use a separate tacho running off the main spindle, as the cheap LED ones off ebay work well enough. If you were to make a separate housing for the VFD, then adding one to the box cover would be easy enough.

They do a similar video for their single to single phase converter.

Bill

After looking at the comments of the ATO video, the motor can not be switched into reverse from the VFD. All it can do is control the motor rpm above the speed of the sprung switch for disconnecting the capacitors, even though they are not connected. To run in reverse the wiring of the motor will need to be altered.

So it looks like a single phase to single phase inverter can be used on a motor that has a cap start still enabled or having the cap start disabled. If the cap start is disabled, then instead of the 0.75kw unit, you will need their 1.5 kw unit. As they say that a 2 times the capacity of the plate rated power is required for the start of a singlephase no capacitor start motor.

On my mill drill recently, I did find a use to be inverting my saw blade and to run my motor in reverse. So for me, I will need a replacemant 3phase motor and single to 3 phase VFD unit .I am thinking of getting a 1.5kw motor that can run at the higher 2880 rpm. That way I can double the rpm and still have the same torque as the slower 0.75 kw motor at 1/2 motor RPM. (25hz the motor would be 1440 RPM) . The gear box lowest speed is still slow enough for everything I need, but the top end is really on the slow side, so that is why I am considering the bigger faster motor. They used to may the Mill I have with the 2880 2 speed motor but stopped doing that line of Mill drills. Maybe that could be in another complete thread. With the 3phase motor and controlled braking, I will be able to more easily do tapping of holes as well.

As for buying the VFD, I have bought all of mine off the local motor sellers. They used to sell complete VFD with a motor package, but no do this service. None of the vfd have ever given any trouble. They also sell the 3phase mototrs to suite the application etc.

ATO do make a single phase to 3 phase motor invertor and on their youtube video, do answer a lot of the comments questions about the setting of their drive etc.

Neil

Contact Newton Tesla for advice on which of their packages would be best. Reverse on a mill is very useful for tapping, very slow in/reverse out.

Malcolm – contact Inverter Supermarket and pick their brains, they were very helpful to me when I went down this route, supplied both motor and inverter.

Chris

Your Mill looks like either the old Warco Economy or Major Mill (depending on size, the Major is pretty big.)

Warco should be able to help with the belt type and size if your existing ones aren't marked.