Author Topic: VFD sizing  (Read 1210 times)

Carpenter84

Re: VFD sizing
« Reply #15 on: December 21, 2023, 01:41:01 PM »
Yes, you can upsize. If the price is reasonable, sure why not. Just don't go smaller. It'll run, it'll likely constantly throw overload alarms, and if you try to resistive brake, they tend to fail in a pretty spectacular way (ask me how I know...)

Also yes, wiring the external switches is extremely easy.
If you choose to buy one, I can help you through the process if necessary. Like I said, I have many, in many different configurations.
Shawn

jpigg55

Re: VFD sizing
« Reply #16 on: December 21, 2023, 02:09:14 PM »
I just found it odd that I see "other recommendations" on the page when looking at a VFD that is both cheaper and higher capacity. Just doesn't make sense beyond possibly a different seller and/or manufacturer.
I'm shopping around trying to compare different ones. Is there any particular brands anyone would recommend staying away from ?
Logan 6560H, SB 9A, Clausing 8520, Sanford MG 612

Carpenter84

Re: VFD sizing
« Reply #17 on: December 21, 2023, 05:44:49 PM »
In my experience the Chinese ones are all the same model just different colour/name. they all work fine. And if you buy it from Amazon or eBay, the sellers will usually exchange the unit if you blow it up.
But frankly, unless you're going with a brand name (the price difference is eye watering) the Chinese ones pretty much all work the same.
Shawn

jpigg55

Re: VFD sizing
« Reply #18 on: December 22, 2023, 12:40:14 PM »
In my experience the Chinese ones are all the same model just different colour/name. they all work fine. And if you buy it from Amazon or eBay, the sellers will usually exchange the unit if you blow it up.
But frankly, unless you're going with a brand name (the price difference is eye watering) the Chinese ones pretty much all work the same.
I see what you mean about price difference.
As for the exchange comment, I've been reading through a lot of reviews on Amazon. Some got decent support or returns, but others didn't. Prime sellers seemed to get the best results, but not always. The biggest bad satisfaction comment I found dealt with people who waited before installing and testing the VFD. Something I hadn't considered myself in that it will probably be spring before I will be having the new shop set up and ready to run wiring. I was also surprised that almost none of the Chinese VFD ratings were in the 90% plus range.
My first thought was to start acquiring the equipment/materials, which some things I will still do, but will probably wait until I'm ready to hook up the VFD to the lathe and test it within a reasonable time of purchase.

I would highly recommend Clough42's YouTube channel videos on VFD's: https://www.youtube.com/@Clough42
Go to his Playlists and find the "Lathe Variable Speed Upgrade" videos.
« Last Edit: December 22, 2023, 12:44:25 PM by jpigg55 »
Logan 6560H, SB 9A, Clausing 8520, Sanford MG 612

4GSR

Re: VFD sizing
« Reply #19 on: December 22, 2023, 05:49:06 PM »
Teco is the last one's I've bought and installed.  I have a Delta brand one on my mill.  It's been running for 18 years now. Also have one made by ABB, fixing to put on a grinder I a while back. So far so good.  The one brand I will not buy is the one that starts with Huy....  Like Shawn said, they are all made in China, some are just a label change, some are manufacture specific.
Ken

jpigg55

Re: VFD sizing
« Reply #20 on: January 20, 2024, 09:54:39 AM »
I was planning on waiting until spring to buy a VFD for the lathe, but recent reports of conflict affecting shipping and shipping costs, I started looking again.
Aside from the obvious ratings like KW/HP and Amps, are there any other ratings/specs I should pay attention to ?
Logan 6560H, SB 9A, Clausing 8520, Sanford MG 612

ddickey

Re: VFD sizing
« Reply #21 on: January 20, 2024, 11:33:39 AM »
They are not all made in China.
My Weg is made in Brazil, KB is made in the USA, Yaskawa made in Japan.
Lenze has models that are made in the USA, i'm sure there are many others.

jpigg55

Re: VFD sizing
« Reply #22 on: January 20, 2024, 12:51:22 PM »
Country of manufacture isn't the only thing that affects shipping. They're already saying crude oil prices will be going up which translates into higher shipping.
Logan 6560H, SB 9A, Clausing 8520, Sanford MG 612

jpigg55

Re: VFD sizing
« Reply #23 on: February 11, 2024, 07:47:03 AM »
I went ahead and bought a VFD since I was ordering other stuff. In preparation of connecting it up, I was re-watching the Clough42 videos and ran into the one on noise: https://www.youtube.com/watch?v=DJfiOqaeFDg&list=PLDlWKv7KIIr_Znhfg8obxwcduFee5Ub5z&index=3
This got me to wondering if anyone has had issues with electrical noise from their VFD affecting other electronics like DRO's,  tach's, etc ?
Logan 6560H, SB 9A, Clausing 8520, Sanford MG 612

Carpenter84

Re: VFD sizing
« Reply #24 on: February 11, 2024, 08:47:29 AM »
I went ahead and bought a VFD since I was ordering other stuff. In preparation of connecting it up, I was re-watching the Clough42 videos and ran into the one on noise: https://www.youtube.com/watch?v=DJfiOqaeFDg&list=PLDlWKv7KIIr_Znhfg8obxwcduFee5Ub5z&index=3
This got me to wondering if anyone has had issues with electrical noise from their VFD affecting other electronics like DRO's,  tach's, etc ?

Nope. I had several vfds in the old shop, and several in the new shop. All of which were/are near computes, cnc machines, tv flat screens, etc. never noticed any interference.
I dont know if the power source matters. I always ran my vfds at 220v with dedicated circuits from the panel.
Shawn

jpigg55

Re: VFD sizing
« Reply #25 on: February 11, 2024, 10:24:36 AM »
Thanks for the info Shawn.
I wondered if his noise issue was due to the 110v supply vs 220 and/or multiple loads on the same circuit.
I just figured I'd ask and anticipate having an issue if multiple people had experienced noise issues.
I might have to change my wiring plan a bit. In my current shop, I ran 220v to all my machines, but ran a 4-wire lead, using one as a neutral, and split off for 110v plug-in outlets to power lights and DRO.
Logan 6560H, SB 9A, Clausing 8520, Sanford MG 612

Carpenter84

Re: VFD sizing
« Reply #26 on: February 11, 2024, 02:16:52 PM »
I would avoid using the same circuit for VFD and anything tho. I know they kick off some gnarly interference, I have seen the flicker in led lights, but have not experienced issues with electronics. Could be distance or shielding, or that I have isolated circuits.
Bring a former electrician i do not hesitate to scramble together another circuit with whatever I have lying around. And always have wire handy.
Shawn

chips and more

Re: VFD sizing
« Reply #27 on: February 11, 2024, 04:19:04 PM »
The internet is FULL of noise/interference! I would not believe everything you read on the internet (except on Machinist Gazette).

Carpenter84

Re: VFD sizing
« Reply #28 on: February 11, 2024, 04:46:56 PM »
The internet is FULL of noise/interference!.

Jeez, ain't that the truth...

But yes, vfd's do create a lot of noise. It's in their functional nature. That'll be the difference between the brand name expensive units and the cheap units - the cheap units lack the extra features like good filtering circuitry/capabilities, the ability to electrically brake, English written instructions, etc... that said, the price difference doesn't make those features worth it to me.
I have blown up 3 or 4 vfd's by pushing the DC braking features (where you'd have a brake resistor on a good unit). The DC injection resistors explode.
But I had this conversation a week ago because I blew up the VFD on the band saw because I had "emergency braking" programmed.
But for the $129 per VFD that I *might* have the chance of blowing up once every 3 years, I think the Chinese vfd's are well worth the price. And it was delivered, installed, and back in service the very next day.  The extra features or durability for me isn't worth spending over $1000 on an Allan Bradly or whatever. If I had a facility where the down time was worth more, then maybe... But not yet.
« Last Edit: February 11, 2024, 04:50:39 PM by Carpenter84 »
Shawn