Thread: Calling all VFD experts for new Buffer

I currently have a hobby lathe with a VFD fitted it is a Folinn BD600-1R5G-2 with the following Specs Rated Power 1.5 Kw, Rated Input Current 14.0 A, Rated Output Current 7.0 A, Adaptive motor 1.5 Kw. I purchased the VFD and motor together from Conon, so I know they play nicely together.

I have recently purchased a buffing machine for occasional use. It is a 3Hp rated at 4.35 amps 415 V delta wound motor that spins at 2870 RPM. I am not sure of the brand of the machine but the motor is Australia General Electric. I was thinking about getting a second VFD. But then I was wondering, can I put a plug on the output of the VFD and plug either the buffer or lathe into the VFD I have. For the sake of this conversation all electrical connections will be made by a qualified electrician. I will not be using them both at once.

A quick conversion shows the buffer to be 2.2 Kw and the VFD is a 1.5 Kw. I cannot ever see me pushing the buffer to its limits as I have been buffing on a little Ashby and Abbott 6 inch bench grinder.

Is this idea feasible, even in the short term to see how well the buffer works?

Here is a photo from the seller. The plan is a paint job and bearing grease. I will add spindles for mops. It appears they are 1 inch thread so I might need to make some adaptors.
Buffer.JPG
Thanks
Steve

Your VFD is a 240V single phase (SP) input and 240V 3P output.

Your buffer. is 415V 3P delta. Short of a complete motor rewind, this means it needs to be run on 415V 3P - if you try to run it on 240V 3P (the output of your VFD) you will get less than half power and risk damaging both the VFD and the buffer.

It could be made to run on your VFD but you would have to use a very soft start and current limit the VFD to no more than 7A out. I would see this as wasted capacity given a 3HP buffer can polish things in about 1/10th of the time a 3/4HP A&A.

To run it at full power and safely from 240V SP you will need a special (ie relatively rare) 240V SP input to 415V 3P output - I can't recommend any as I have no direct experience with these VFDs but others on this forum have with a brand called Ecogoo.

That buffer looks like it has an old school motor. Efficient high speed buffing really requires 3600+ rpm operation but trying to achieve those rpms on an old motor may not be possible and may produce some interesting noises from both the motor and the VFD. This is because of the magnetic characteristics of old motors. One old motor I tried to speed up started making these noises at just over 50Hz and would not run at a supply frequency above 57Hz.

That motor is likely 40’s vintage.

As Bob says - not many options since it’s 415 delta, but I’d be pretty confident that as long as the motor isn’t stuffed it would run “OK” on one of the Ecogoo 220 1ph to 380 3ph VFDs.

I’ve no experience with running the older motors at other than 50Hz though - so can’t comment on that aspect.

Steve

Thanks for the information so far. As for the variable speed part I am not fussed about that. Most buffers just run at one speed and that will do me. As for loss in efficiency, again this is not that big an issue. Most home buffers are no more than 1Kw so even running at 50% it is above that.

So I guess the short question is this. Is there a way I can run this at home of 240V. I have a 15 amp outlet and can put in a 20 if needed.

Thanks

Steve

Grab one of the Ecogoo 2.2kw 220-380v VFDs. About $150 delivered from AliExpress.
If it won’t run on that, then I’d say that anything other than a Rotary Phase converter or proper 3ph will be an issue.

Steve

The last couple I got were identical to the Ecogoo VFD, but badged NFlixin. Manuals are identical (9100 series), and seemed heaps more listed than Ecogoos on AliExpress. White housings I think signify 240 1ph - 240 3ph, and black enclosures 240 1ph in, 415V 3ph out (at least in the smaller sizes up to ~4hp). DAMHIK....
Cheers
Si

Thanks Simon.
I need to order one shortly -
any recommendation for a particular seller??

Steve

I had a look at NFlixin brand. I could not find the 220 volt single phase input with 380 Volt three phase output in a 2.2Kw. I am sure they are there, I just did not pick up the right rock.

I would also be interested in a supplier that people have had a good track record with for this type of VFD.

Thanks for the advice so far. I was going to order one tonight but I might give it 24 hours.

Steve

Hi Steve
Latest ones I got from
https://nflixin-inverter.aliexpress....56bb5618PBzdFY
in about 7 days (2 in last 2 months)
1 happily spinning up the giant D/E grinder you kindly donated to me!
Having the option by VFD to gradually build up speed on a 14" grinder with used wheels is nice. And dressing at non-resonant speeds good. One of those wheels letting go at full speed would be an experience to be missed!
Cheers
Si

Hi (Reidy41) Steve
This is the listing for the one I got, which I think matches what you are after:
https://www.aliexpress.com/item/1005...1f1b4c4dbVoRcP
Hope that helps you find it.

Delivery has been excellent on these for me (~7 days) - similarly for a colleague who received one over the weekend.
Cheers
Si

Hello Si

Thanks, out of curiosity it appears I can get it from China, Spain or Russian Federation. I am assuming China is the prefered option.

https://www.aliexpress.com/item/1005...56bb56189qB82W

Steve

Hi Steve
I got mine from China, I think that if you select other regions it won't allow delivery to Oz. I think Spain services Europe, not sure about Russia. Have seen this with several other AliExpress sellers.
Cheers
Si

Originally Posted by SiJ

Hi Steve
Latest ones I got from
https://nflixin-inverter.aliexpress....56bb5618PBzdFY
in about 7 days (2 in last 2 months)
1 happily spinning up the giant D/E grinder you kindly donated to me!
Having the option by VFD to gradually build up speed on a 14" grinder with used wheels is nice. And dressing at non-resonant speeds good. One of those wheels letting go at full speed would be an experience to be missed!
Cheers
Si

Thanks Si - and good to hear you’ve got that grinder running (with hopefully no dramas)

Steve

Thanks Si for the lead and thanks for the other advice I have received. I have placed an order so I should have a VFD inbound. I will update once I receive it. Once the Buffer is operating I am sure there will be a couple of questions.

Steve