VFD Variable frequency drives

NEL957

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Need help
I am looking to buy a VFD and I need your help on a good one and not a dud. Anyone that has experience and maybe a good supplier would be very helpful.
What I wast to do is run a 3 phase mill on single phase power.
Thanks for all the help
Nelson
 
My only experience is with a new 3 HP Chinese rated VFD bought off eBay for $109 and shipped free from China. The instructions are difficult to understand well, but I was not doing anything too arcane in hooking it up to my surface grinder, just an external on/off spindle switch, and an external potentiometer to control the frequency/motor rpm. The import VFD's are known for less than robust keypads so I just bypassed it for the controls I use regularly. It works just fine, no issues with buying it or with hooking it up. The import VFD's are a LOT cheaper than anything built in the USA, especially if you get it from AliExpress, direct from China, instead of through eBay, like it did. You take a chance on the imports, but you can also save a LOT of money... I have friends with import VFD's and have personally heard no stories of getting a "dud."
 
Another forum will tell you in no uncertain terms that your shop will burn to the ground the second UPS drops off your new Chinese VFD. With that sort of strong recommendation, I ordered a 2.2Kw Huanyang off of eBay. Very likely the same unit Bob has, The instructions are average chinglish. There is enough info readily available on the net to set one up without ever opening the manual.
 
That is exactly the one. Yes.


I've found that heavy or bulky items do not do well off Ali* in small quantities. The shipping amortizes much better when spread across a container load. Tis why many of my purchases originate in City of Industry, Ca.
 
So a number of different views on these Chinese eBay VFDs. I have heard of at least two other individuals that had DOA units, the vendor did take care of them, but do not expect any warranty or installation support. I have had enough issues with the HY VFDs and there are even cheaper clones sold on eBay, that I usually suggest paying a little more and getting one that comes with a warranty and some installation support. There are some cases, where you just can't beat the price of the HY VFDs for the application, such as a 5-10Hp VFD with a single phase input. So my major problem with the standard HY VFDs is they do not have sensorless vector control, they do not have the braking circuity for an external resistor built in (even though the terminals are there), they do not autotune the VFD to the motor. Sensorless vector control gives you significantly better low end motor control and higher short term overload. There is less of a need of an external braking resistor on a mill, but I have heard of people tripping the VFD when turning down the speed rapidly. I have also had issues with the terminals being too small for the rated current and crimps size So you pretty much get what you pay for, they all will work, if you are looking at rock bottom price then get the HY (there are some US shipping vendors on eBay, although there support is not to good). Otherwise if you want a bit better performance and support then look at something like a Teco L510 or N3, Hitachi, WEG or Auotomation Direct VFDs . I have worked and done the programming with most of these units, on a mill it is very basic.

There are several US vendors that I have purchased VFDs from, the ones I recommend are:
http://dealerselectric.com/230V-single-phase-input.asp
https://www.driveswarehouse.com/index
 
I want to thank each and everyone for your comments. I've read almost everything I could find and kind of hesitate, but that seems like the way to go. Just one thing about Teco / Westinghouse is a China manufacturing.
Again thanks
Nelson
 
I have heard of at least two other individuals that had DOA units
Hearsay not accepted.
I have had enough issues with the HY VFDs and there are even cheaper clones sold on eBay, that I usually suggest paying a little more
"A little more" starts at about double the cost, and does not include free shipping.

I assume that the units you posted are all made in China. I know you have LOTS more experience with these things than I do, and I respect your opinions. You also do this stuff professionally, which colors what things are most important to you. I am just a frugal pensioner...
 
Hi Nelson,
Just about everything these days seems to be made in China, or has parts from there. I think the problem arises is that everything is built to a price point, so it is not as much where it is made but how it is made and the QC. I have become a little more jaded on buying some things direct from China through eBay, as it is impossible to return (due to the shipping cost) and essentially no technical support should you have a problem. The Teco VFDs are very good, I have heard of one individual that had some problems with an L510 not working well with his mill motor, the Teco N3 has been around for a long time and is very similar to the Automation Direct G3, both which are very good. Many of us have used the Hitachi VFDs (WJ200), I have not heard of a problem or failure. The programing on many of these VFDs can be a bit daunting, but not so hard once you get started. If you don't know or have question just ask and I am sure we can help. I understand the cost issues, so if the budget is limited, then the HY is hard to beat, especially if the money is tight. It is a learning process of knowing the different features and just buyer beware. I think a VFD adds a lot of features and controls, and at fairly reasonable cost at the 3Hp and smaller size.

Drive Warehouse has free shipping on their VFDs, I have purchased quite a few from them and they tend to have the lowest pricing. They also extend the manufactures warranties to a total of 3 years for drives, although I have yet to see a major brand VFD fail in this time frame.
Mark
 
My prefered vendor is Automation Direct. Good, readable documentation and U.S.A based tech support. Not the least expensive, but a good value.
 
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