Thread: 3ph to 3ph VFD

Originally Posted by cba_melbourne

- I would not recommend these low cost Chinese VFD, no matter how tempting the price seems. Better look on eBay for a "new old stock" VFD from a reputable maker. Or a used VFD that is not too old. Why do I say that? I think that Chinese speed controllers, regardless if DC or VFD, are badly executed using inferior components. Cheap yes, but all things considered, pretty poor value. Yes the Chinese can very well make good speed controllers, but these cost more and bear the "western" brand names of the companies that designed them and provide the critical components.

Hi Chris,

I disagree, I have any number of Huanyang VFD's and they represent excellent value for money, I would recommend them without any problem. Bear in mind that the majority of these are not really being used as VFD's they are more often used in a home workshop environment to provide single phase to three phase conversion. Even if you zap a Huanyang, the IGBT's and all the "consumable" parts are cheap and readily available.

Last count I think I have at least 10 chinese vfd's, I also have Danfoss, Teco, Mitsubishi and PDL.

Ray

I now have 8 cheap Chinese VFDs, 5 on machines, 1 set up as a motor tester and 2 for spares and future projects and am very happy with the way they run. For a very modest investment I get access to most small (and often very well priced) used entry level 3 phase machinery (I only have single phase in my shed), soft starts, improved stopping speeds and modest levels of speed control. More torque at low speeds would be useful but apart from this I cannot think of anything else I need from these devices and I'd say like Ray I have obtained excellent value for money.

WRT "cheap Chinese" VFD's, I agree with Bob and Ray. I can't fault them for my particular use. I now have 3 but in the not too distant future it will be 4.

Simon

I think a bit of horses for course applies with this sort of stuff.

I'm just a hobby level operator with mid level Sherwood drill press and a small Woodfast WW lathe that I purchase new, while my Hercus metal work lathe and Italian linisher cost me nothing. From my perspective and budget spending any more than a couple of hundred on fitting a VFD for each of these machines would be overkill. If I had spent a couple of grand on a quality machine I'd be more likely to match that with an appropriate VFD. The one machine I had some concern about using a cheap VFD on was the Clisby Compressor but all I am using a VFD for on that machine is as a 3Phase soft start supply, and so far it's woking really well.

Yes I also do have some Ozito power tools, an angle grinder I paid $39 for years ago that I cannot seem to kill. A big demo hammer/drill that cost $69 has been fantastic, a ROS that turns my hands/arms to jelly after about 20 minutes us,e and a biscuit cutter that has lost most of the little bits and pieces attached to it.

Michael and Simon, thanks, I'll take your advice and suck it and see with the fan caper.

Originally Posted by PDW

Yep, that's the point I was trying to make in my first post.

The only way to get a torque increase at low Hz is to increase the motor HP in the first place regardless of vector VFD or not. Now it appears the OP's mill has back gearing in which case things are not so bad - he gets that mechanical advantage.

I don't recall what spindle type he has, if he's said, but I do know that I'd be reluctant to attempt a 45mm hole in my B/port even though it goes down to 78 rpm (I think, I'm a long way away ATM). The holding ability of an R8 collet would make me hesitate. If the machine has a more capable taper spindle, 30 or 40 taper or similar, no dramas. MT4, fine. MT3, well, I wouldn't - there's a reason drill bits this size have MT4 shanks.

PDW

G/day PDW, it has a 40 spindle and it weighs 1600kgs, spoze it's not a deal breaker if i have use a few sizes to get a decent size hole, or just use the hercus drill, the test drive will tell me what it will or won't do i spoze. Regardless of that I think it should do most of the things that I might want to do with it.

shed

Originally Posted by RayG

Yep, that's pretty much my approach.. works most of the time.

Nice work getting a vector drive at a bargain price.. you will have to enable that function and look for an autotune function to "tune" the vfd to your motor charactestics.

But....

Having done all that and you'll get full motor torque across the speed range, you still won't get the same as having a gearbox... a gearbox MULTIPLIES the torque, a vector drive just means you don't lose too much.

Still, it will save you lots of gear changes and belt swaps..

Ray

PS Did you ever use that 5hp motor for anything?

G/day Ray, I did a post to you and cyberspace must of ate it? Here goes again.
It looks like I should get 3440rpm if I can get 120hz in the highest ratio, total low ratio will be about 10.75:1 and at 20hz the spindle speed will be about 36rpm.

Ha....the 5hp motor is supposed to drive the linisher that I didn't build yet,
do you want to borrow it back ?

shed

Originally Posted by shedhappens

G/day PDW, it has a 40 spindle and it weighs 1600kgs, spoze it's not a deal breaker if i have use a few sizes to get a decent size hole, or just use the hercus drill, the test drive will tell me what it will or won't do i spoze. Regardless of that I think it should do most of the things that I might want to do with it.

shed

40 taper is fine, no issues there with holding ability.

If I can I usually drill out for the web size then shove through the drill size I want the hole to end up at, but this assumes the machine has the torque, suitable rpm and rigidity. Otherwise step drilling is the sensible approach, though you still need to get the speed down.

I can't see you've a lot to lose by wiring the thing up and having a go. I think that the range of 20-100 Hz is likely to give you the best results, if the vector drive extends that, bonus.

PDW

Originally Posted by shedhappens

G/day Ray, I did a post to you and cyberspace must of ate it? Here goes again.
It looks like I should get 3440rpm if I can get 120hz in the highest ratio, total low ratio will be about 10.75:1 and at 20hz the spindle speed will be about 36rpm.

Ha....the 5hp motor is supposed to drive the linisher that I didn't build yet,
do you want to borrow it back ?

shed

Hi Shed,

High speed limit is a always a bit of suck it and see, some motors seem happy at high frequencies others just don't handle it. The numbers for low speed look fine.

No use here for the 5hp, There's another one here anyway...

Ray

The Powtrans drive are a very good unit and NC Archer has had a fair bit of experience with them over quite a few years. Most of the Clearvue cyclones in Australia are powered by them and in that time we had one failure and that was caused by the installation. Back up service response from the factory if needed is next to immediate and never any longer than a few hours. Powtran chased me to distribute their product line over quite a long time when I was buying them by the box full but I declined and it looks like someone else is having a go though I think the price is a bit steep. Another Aussie retailer having a go at the consumer and I say that having a fair idea of what he would be buying them for.

Originally Posted by NCArcher

You won't be disappointed with the PowTran drives. They are a great drive for the price.
SV control is selected at parameter F00 = 1 and the Auto tune Ray mentioned can be found at parameter b11.
I have a manual here if you need a hand when you get it up and running.
If you punch in the motor nameplate details in parameter group b it should run straight out of the box using the pot and buttons on the control panel.

NCArcher thanks for your post, I thought I would have a crack at it and it helped me join some dots and zero in on the pertinent pages in the manual.
Pity I didn't get it working tho first I was foiled by the plug not being in properly, I found that by turning on the feed motor and it only hummed, I went and pushed the plug a away it went so I then did all the inputs again, still no joy tho......

This is what I did, (maybe I also did something else that shouldn't have? lol...tiz a distinct possibility)

pg 54, sensorless vector control, I keyed in F00 = 1

pg 122, I keyed in the name plate parameters at b08,
b00 frequency = 50.00
b01 motor 1 rated current = 5
b02 motor rated voltage =440
b03 motor 1 pole-pairs =2, and tried = 4 also, dunno about this? It is a 4 pole motor I suppose, so should it be =2 for 2 pairs of poles or =4 for 4 poles?
b04 motor rated speed = 1430

Then I went to b11, pg 123, and selected number 3, inverter rotation measurement, (the inverter automatically start parameter determination) I pushed the fwd button and it went through the CAL's and the spindle started weakly spinning and I guess it got to 150 or 200 rpm and then end.

Looking at the manual now I see I missed this bit "powerConfirmed the inverter power matches to the motor power ,reset the factory value of y00 =5Select"

Anyway..... nothing earth shattering happened, after several times checking the inputs when I pushed the fwd button nothing much happened, a slow turning chuck in the spindle that I could stop with my tongue if I wanted to.

Hopefully someone can hold my hand and guide me in the right direction.

The manual is here (6mb) http://m-and-r-controls.co.uk/data/p...110716E%20.pdf and the VFD model is PI8100.

thanks, shed....

and some pickies of what I was seeing.....

Hi Shed,
b03 should be set to 2 for a 4 pole motor.

Any display that starts with E is an error. EoL is too much load and EoCP is over current.
When running the auto tune the motor must be unloaded. It needs to be uncoupled from the machine.
Set b11 = 3. The display should read RUN. Hit the start(FWD) button and the auto tune should begin. Display will read CAL1..CAL2..CAL4 as it steps through. CAL1 and CAL2 are static measurements so the motor will not turn till it gets to CAL4.
When it says END you can hit the stop button then set b11 = 0.
If you still get errors, try upping b01 to a higher setting. Don't forget to put it back when the auto tune is finished.

Hi Shed,

Just to get it running try turning off the sensorless vector control for a start, then when you're happy that's all good, take your belt off and do the autotune.. ( the motor belt!! that is...)

The switch back to vector control.

Ray

One of the advantages of the Powtran is that a keyboard can be programmed by someone on another drive and then sent to someone if they are having problems to be uploaded into the drive. I also use two keyboards in different parts of the workshop to control mine though others have found two keyboards was not successful.