Looking for input on VFD.s

mksj said:
Lenze/AC Tech are well built VFD's and have been around for years, they are available in NEMA4X so would be a good alternative to the KB sealed VFD's in a dusty or wet environment, or used w/o an enclosure. They are good as a stand alone unit, but they have a limited number inputs and programming options, they also are a bit more expensive then comparable VFD with more features. Models under 40Hp do not have a dynamic brake transistor built in so would not support an external braking resistor. So a bit limited and dated design, I feel there are better VFD options at the same or less price range.
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The Lenze 3hp I bought a couple of years ago can, and does support an external braking resistor option.
 
It requires a braking module according to their spec sheet, the module has the braking resistor with additional connections, but they are expensive. Might also be model specific, as I haven't installed these, it may be different as to how I read the instructions. I did install some KB models where they required use of their external braking module and it was as expensive as the VFD.

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mksj said:
It requires a braking module according to their spec sheet, the module has the braking resistor with additional connections, but they are expensive. Might also be model specific, as I haven't installed these, it may be different as to how I read the instructions. I did install some KB models where they required use of their external braking module and it was as expensive as the VFD.

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Correct Mark, it did require a "dynamic braking module", not just a simple resistor. While somewhat expensive( about $120 when I bought it ) was/is very effective. I'm a pretty careful ebay shopper and scored the "new open box" drive unit for $275. So, for under $400 got a really good quality "Made in USA" externally braked drive. Very happy with it. I think this current model drive retails at around $500 nowadays, and the braking module is $150.
 
I have not tried the Vevor VFD's. It looks like many of the MIC VFD's.

I have one old Schneider VFD no issues at all. I had one MIC VFD looks similar to the Vevor fail with very little use. Hopefully their VFD's are better quality then their drill dispenser cabinet, they are okay but definitely not a Huot.
 
I would be very hesitant to buy an electrical component like a VFD from Vevor, Amazon or eBay if it isn't clearly marked as a specific brand I could research.

I would stick to something you can find on Wolf Automation or Automation Direct....if you have problems they will help. If you go with Vevor or Amazon you're really going it alone. I have read posts on other forums that claim the cheap import VFDs are often the rejects from bigger brands and have high failure rates....no idea if it's true, but I wouldn't risk it.
 
The reason I was thinking about Lenze is that a few years back I saw a government auction of several Standard Modern lathes in Virginia and they
all had blue Lenze drives on them. Seems the government liked them- probably had to buy US made stuff in the contract
Anyhow if you got one as a package deal it would be nice, but I probably wouldn't buy one new for the reasons Mark mentioned
 
I have 4 VFDs. Have always bought the cheapest I could find and never have had a bit of trouble with any of them (except for poor manuals).The youngest one has been going for 2 years now, the oldest for 7.
Just my 2 cents ;)
Aaron
 
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