VFD questions

Over-rating is over-rated...;-)

RTFM...

First, take a photo of your motor plate. It lists things like amps or watts running and volts as well as a few other items.

For the surface grinder, you need a few features, just 3 phase output, variable speed good, and vector control not needed.

Next shop for your VFD, when you find what you like, download the manual. If a manual can not be downloaded, PASS.

In the first pages of the manual there should be a compatibility chart showing different motor sizes supported with single and 3 phase input.

The ratings will be in both HP and amps or watts, the terms from your data plate.

This chart should have the suggested model for your motor rating with single phase input, buy that one.

Read the rest of the manual to confirm it will meet your needs and you understand how to install and setup.

Sent from my SM-G781V using Tapatalk
 
Over-rating is over-rated...;-)

RTFM...

First, take a photo of your motor plate. It lists things like amps or watts running and volts as well as a few other items.

For the surface grinder, you need a few features, just 3 phase output, variable speed good, and vector control not needed.

Next shop for your VFD, when you find what you like, download the manual. If a manual can not be downloaded, PASS.

In the first pages of the manual there should be a compatibility chart showing different motor sizes supported with single and 3 phase input.

The ratings will be in both HP and amps or watts, the terms from your data plate.

This chart should have the suggested model for your motor rating with single phase input, buy that one.

Read the rest of the manual to confirm it will meet your needs and you understand how to install and setup.

Sent from my SM-G781V using Tapatalk
Awesome, will do, Thanks
 
A 1.5kW vfd would be sufficient to run a 1hp surface grinder
I have tested very inexpensive vfd’s for many different purposes.
I have not experienced any failures with inexpensive vfd’s in real life operations on lathes, milling machines, packaging equipment and food processing equipment.

Have a look at a Huanyang 1.5kW single phase input 3 phase output
The manual is chinglish but easy enough to use
Programming is relatively simple
I ran my Boyar Shultz on it for a couple weeks before I upgraded electrical distribution

Good luck, whichever way you go
 
After setting up two VFDs, the quality of the instructions is probably at the top of the “important features” list. If you’re shopping where there are reviews, look at them (with your BS filter turned on). Filter out bad reviews that read like the writer was clueless but if you see the same complaints over and over they’re probably legit. I set up an Automation Direct first with no help other than the instructions. The second one was a Chinese brand with instructions that were very difficult for me to understand and I got a lot of help from people here.

One feature that I really like is the soft start. It doesn’t have to be super slow; even a 1 to 1.5 second spin up time is more pleasant than full power instantly. As far as oversizing, Automation Direct told me there was no need with their VFDs and I’ve had no problems with a 1 hp VFD on a 1 hp milling machine. Keep in mind that 1 hp = .75 kw so even a 1 kw rating is oversized and 1.5 kw is 2 hp.

Another feature that I like is the ability to use the factory original control switches. It takes some configuration but isn’t difficult with good instructions. That ability is pretty much universal with all VFDs.
 
I strongly suggest you get a VFD that comes with a dustproof enclosure. I built an enclosure, and it works, but it was a hassle.
 
What about digital phase converter? They have none of the control functions of most vfds have, they only make 3 phase out of single and are way less expensive. I have no experience with them but I looked into them when I acquired a 3 phase motor equipped bandsaw and I have only single phase in my shop.
 
The so called digital phase converter DPS (Digital Phase Shifter) sold on Amazon and eBay are not true 3 phase converters, they are a static converter with a few start capacitors that are digitally switched in when the motor starts. There is no generated voltage on the wild leg until you hookup the motor to it. Phase Perfect sells true three phase digital converters that generates the third leg and passes through the other 240VAC legs similar to a RPC. It allows across the line motor starts and full 3 phase power from a single phase power source. The caveat like an RPC, is a neutral connection cannot be used for the 3 phase output w/o a delta to Y transformer. The smallest Phase Perfect is rated at 5 Hp motors, and about 5X the cost of a 2 Hp VFD. If your bandsaw is 3 Hp or less your would probably be better off with using a VFD, use 3 wire control and use a momentary stop and start button. If larger Hp, then a RPC or Phase Perfect may be more suitable as a plug and play option.

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Hello all, Here to ask a couple questions about a VFD. I am ready to pull the trigger on a VFD purchase for my Harig 618 surface grinder and I’m stuck,lol. Comes down to the Fuji or the hitachi wj200 however I’m not sure even which one to order. There’s so many. Was hoping for a little guidance. Thanks

I have both. I would choose the Fuji. The WJ200 is an excellent VFD with capabilities FAR beyond anything you will ever need for your surface grinder and is MUCH more complex to program than my more basic Fuji. My Fuji is about 15 years old and I have not had any problems with it.
 
I have the Huanyang 5 hp on one of my lathes with a 2hp motor and it works fine. I also have the Fugi Mini on my McClane mill with 3 hp motor. Both work well for me being I am a hobbyist The Huanyang is more in the price range of a hobby shop. But the Fugi is more on an industrial range and expect to pay double for it. The Pot went bad on the Huanyang but I just added a remote Pot and it fixed the problem for around $10. Just be careful with the Huanyang there are several copy-cat versions of it on the market. If you have never used a VFD they are not Plug and Play devices. They need programing and the instructions are usually in Chinglish. After 2 years of trying to learn how to set the peramaters of my Huanyang I finally watched this video. It is not in English but has subtitles and I read the subtitles and got mine to work .

 
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you want a VFD bigger than your HP. When I was looking, the VFD vendor told me to up it do not go for the rated HP. I listened.

The only VFD I've had go bad was a brand name mid price unit that was a close rating to the motor. Since then I've used china brand ones that are at lest 1hp over rated motor power and have had no issues.

The branded one (matched motor HP) made it about 2 years , the oldest off brand china one (over HP rated) I have is about 6 years old.

Mileage may vary , and all that :)

Stu
 
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