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crancshafter
05-28-2012, 01:02 PM
Hi all.
I have a little problem(I hope)
I have 1phase 16 amp in my shop.
My new/old mill have a 220v 3phase 3.6amp.2 speed motor. Do you see any problem to use a inverter to drive the mill?
Will the inverter shown in the link below do the job. (I will use: input 220v 1phase and 220v 3phase output.
http://viewitem.eim.ebay.no/HIGH-QUALITY-3HP-22KW-10A-220250V-VARIABLE-FREQUENCY-DRIVE-INVERTER-VFD-NEW-j2/140686149359/item

Best regards

CS

oddball racing
05-28-2012, 01:13 PM
Actually, That vfd is 3 HP, a little overkill. Three of my mills are all using 1 HP vfd's. Over here in US there is definitely a cost saving buying a 1HP over a 3HP. Check to see if they offer smaller units. As to that particular Model, I don't have any Idea on it's history or reputation. perhaps others will chime in.
The Best , Mike

lakeside53
05-28-2012, 01:19 PM
It will work if the vfd actually puts out what is adverstised. Of course, it looks to be about 3X the size of your motor. It is the "bottom of the barrel" no-name Chinese import type. Do you have any other users locally you can talk to about their experiences?

What are the motor currents in both speeds? Typically you would choose the high speed windings and just use the vfd to vary the speed to simulate the lower speed selection. If it's a Dahlanger wound motor, the high speed will be about 2X the HP of the lower. Your current rating indicates it's about 1hp, but is that for both speeds?

Personally... I do not buy the VFD you have shown. For not a lot more money, you can buy a decent name brand (in the USA).

crancshafter
05-28-2012, 01:40 PM
oddball/lakeside
I think I will run the motor on high speed.
I do not know this inverters but they sell for a good price I think.
Ok, I could have buyed from the States but the posting to Norway would have killed me, nearley;-)
Anyone in the UK tryed this Inverters?
Sir John mybe?

CS

lakeside53
05-28-2012, 01:45 PM
Don't be so sure on the postage! There are several USPS flat-rate options. I sent a similarly sized package to Norway last year for about $40. Of couse, you have to find a seller that will ship to you (get a quote before buying)

If you didn't want to spend the money on a Hitachi VFD (like WJ200), my second choice would be a Teco. I've had good experiences with both brands.

J Tiers
05-28-2012, 11:41 PM
That is a chinese inverter, of unknown quality.

You would do better to buy a good inverter. In Norway you should be able to get a better type... for instance Invertek (UK), or Vacon (Finland).

Invertek is very good at the lower power inverters like that. Vacon has them, but is more expensive.

EVguru
05-29-2012, 05:58 AM
I have three of those inverters in use. They work just fine.

The power stage is based on 1200 volt 25 amp IGBTs, so it's got decent margins and the filter caps and power devices are Japanese brands. The soldering is just about OK (seen worse in European, US and Japanese high end scientific instruments!), but they do leave out some features (somewhat at random it seems). The dynamic braking circuit is almost always missing (not been a problem for me) but DC injection braking is available. The RS485 communication chip is often missing and on the latest two I bought the two auxillary outputs were missing their opto-couplers. For once I actually wanted to use one and had to solder in a coupler.

The plastics are cheap, but OK and I wouldn't want to operate it from the membrane keypad (it wouldn't last long), so external switches are the way to go.

The latest version of the manual is reasonable and certainly better that the Eurotherm one! I wouldn't hesitate to buy another one for use on an ordinary lathe or mill.

crancshafter
05-29-2012, 05:05 PM
Hi Paul.
You have a PM.

CS

lakeside53
05-29-2012, 05:36 PM
Another high quality vfd from your part of the world is made by AB.