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dodge at4
27th Nov 2017, 03:55 PM
hi all , after buying and using a couple of hangyang VFDs on some of my workshop machinery , i needed another for a gmf senior grinder as i needed to polish some alloy car wheels.
i like the hangyangs with the speed controller knob , so while looking on aliexpress came across these VFDs called a xinshuang-yuan.
price was a round $106au shipped and it has a speed control knob so i thought i would give them a go.
the gmf grinder is a 1-1/2hp so i brought a 2hp VFD, converted the grinder to delta, fitted new bearings and a coat of paint.
VFD was very easy to fit up , easier to set the parameters than the huanyang, less to set as well, good instructions and diagrams.
even comes with extra cable and a little box to remote mount the speed control ,led thingo.
have been using the VFD for a couple of months now and i am very happy with it so far and have polished the car wheels no problems.
i did not know what to expect for $106, but i think i will get another one for my lathe to save changing belts
thought i would post my experience with the vfd as others might be interested in one

cheers all

BobL
27th Nov 2017, 06:29 PM
The xinshuang-yuan looks like an HY clone which is a non-vector drive VFD which means but for a lathe you will still need to change belts.
To further reduce belt changes I would recommend getting a Vector Drive VFD.
Some of the cheaper ones do claim to be vector drive but it turns out they are not.

Recently I have purchased and been playing around with Powtran VFDs which are a true Vector drive unit.
Single VFDs can be purchased direct from the factory and they are built like a brick outhouse compared to the cheaper units.
They have many more useful features and don't cost much more than the cheap VFDs
For a basic review of some features - see here VFD install summaries (http://www.woodworkforums.com/f271/vfd-install-summaries-213878#post2023935)

dodge at4
27th Nov 2017, 08:27 PM
hi bob
why do you say this vdf would be unsuitable for a lathe, low speed torque, please keep it simple for me:doh:

BobL
27th Nov 2017, 09:08 PM
OK.

A non-Vector drive VFD has full power between 50Hz and about 100Hz, above that frequency the power slowly starts to drop off.

Below 50 Hz the power is proportional to frequency, so at 25Hz it has 1/2 the power it had a 50Hz, and at 12.5Hz it has 1/4 of the power at 50Hz etc.

It depends on the motor and the VFD but for a 50Hz rated motor you don't really want to be using you VFD above 125Hz. Some folks run there stuff at 150Hz but long term I worry about bearings at these speeds.

In practice I found I had enough power when the VFD ran between 25Hz up to 125Hz (or a working a 5:1 speed range) without changing belts.
I call this, "the standard setup"

To get a wider speed range I doubled the power of the motor and also used a Vector drive VFD both of which approximately double the available output power
This gives me the same power range as the "standard setup" from about 6Hz up to 125Hz or 20:1 speed range.
In practice a Vector drive generates more than double the torque below 10Hz compared to a non vector drive so its even better than this.
On my WW lathe the non-vector drive HY won't even turn over at under about 8Hz.

Now I found I rarely need to change the belt except for the very slowest speed activities.

dodge at4
27th Nov 2017, 09:24 PM
ok thanks i dont want to stall the thing drilling a large hole at low speed
do you have a link to one you would recommend for 2hp thank you

BobL
27th Nov 2017, 10:19 PM
do you have a link to one you would recommend for 2hp thank you

Unless you go through Alibaba there's no web link where you can buy .
However you can buy direct from the factory.
Just email the Powtran factory for a quote and cost of shipping and payment details.
The contact email is [email protected] and the contact name is Nicole Chan.
You have to be precise in telling them what you want but they do know their product and can provide good info if you need it.
Payment can be done via PayPal.

There are two 2HP ranges to choose from.
The PI9130 series are pro level units
There is also a smaller "budget" level series PI160 - it does not have the dual line display or speed sensitive knob but does have Vector control

The website is so-so but you can see the specs for the PI9130 series @ PI9130 High-performance universal vector control inverte,Products,POWTRAN, VECTOR CONTROL INVERTER,AC DRIVES,SOFT STARTER,SERVO ,DALIAN Powtran technology co.,ltd. (http://www.powtran.com/en/productpage38.html)

The last quote I had for the PI9301R5G1 was US$115 and shipping was US$40.
The won't do slow boat postage from China.
I ordered mine on a Thursday night and got it delivered on the following Sunday (3 days)

The PI160 (PI160 2R2G1) quoteI got a couple of months back was US$85 and shipping was also US$40.

If you want the high speed brake circuitry included in the VFD add a Z to the end on either model
i.e. PI91301R51Z and this adds and other US$5 to the price.

The ClearVue dust extractors that are imported in Oz are mostly using these Powtran units and they are proving very reliable.

dodge at4
27th Nov 2017, 10:25 PM
ok thanks for your detailed post and time , there quite cheap so i will get on to them for a christmas pressy cheers :2tsup:

j3dprints
3rd Dec 2017, 08:40 PM
Bob if I buy a 2.2kw 3 phase motor does that mean a PowTran 2.2kw VFD will do the job or do I have to uprate it?

I'd like to get either a 2.2kw or 1.5kw motor (not sure if my 10 amp outlet can handle 1.5kw with other stuff on it), I'm also not sure whether to go 2800rpm 2 pole or 4 pole and Up the Hertz on the VFD. Going to go on a single pulley system milling machine.

Thanks.

BobL
3rd Dec 2017, 10:04 PM
Bob if I buy a 2.2kw 3 phase motor does that mean a PowTran 2.2kw VFD will do the job or do I have to uprate it?

I'd like to get either a 2.2kw or 1.5kw motor (not sure if my 10 amp outlet can handle 1.5kw with other stuff on it), I'm also not sure whether to go 2800rpm 2 pole or 4 pole and Up the Hertz on the VFD. Going to go on a single pulley system milling machine.

Thanks.

On a lathe or milling machine you are much better off going with a 4 pole (1440 rpm) motor as this gives you a wider frequency range.

A 4 pole (1440 rpm) motor can be easily spun up to 125Hz (3600 rpm) and retain at least 1/2 the original motor power

On the low frequency side the half power frequency is 25 Hz so this is 720 RPM.

If you change the motor to one with double the power then you will have full original motor power from 720 - 4300 RPM

As I said in my post above this gives a full power speed range of 5:1
Then add a vector drive VFD and that will give you 10:1 at full original motor power
It depends what you do, but in practice I find I can generally perform most lathe functions with half power so that gives a speed range of around 20:1

Using a 2 pole (2880 rpm) motor, spinning that at 150Hz (that's 8640) is asking for bearing failure.
To stay conservative I don't spin 2 pole motors above about 75Hz (4300 rpm) which reduces the speed range significantly compared to a 4 pole motor.

What other stuff have you got running at full power at the same time as your millon your 10A line.

I have 4 , 1.5kW VFDs on one 10A line (MW lathe, WW lathe, DP and Grinder) they are often all turned on but of course not running at full power at the same time.

I have 2 machines running VFD on 2 pole motors, My WW Band saw and 150mm x 1m long linisher. They are set for max frequency of 75Hz.

There's no need to over rate the Powtran VFDs - that are designed to run machines like pumps at full power 24/7.

j3dprints
3rd Dec 2017, 10:15 PM
Bob, you are a legend, thanks I have been trying to find this info out for a while. I will grab a 4 pole motor.

At the same time as the mill is going I would anticipate having mainly the 3 drives for each axis on the milling machine going, as I intend to CNC it. If I go with servos these would be 400w,400w,750w, obviously not all running at max power at the same time. I guess I could plug these in to another line if there was benefit.

Your recommendation for Powtran seems solid, I will pick one up I think, if you have motor recommendations I'd be interested too. So far I'm just going off ebay. I will enquire as to whether each motor can be delta/star wound (whichever is low voltage).