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The Artful Bodger
10-18-2013, 02:20 AM
I have received a ruling that provided I keep all my domestic chores up to date and performed to satisfaction I may convert my mill to 3 phase and VFD operation.:)

So I am shopping around for a suitable VFD, I have been offered a CFW 10 and a 2 hp 3 phase motor. I need 1 phase in (230V).

http://www.weg.net/us/Products-Services/Drives/Variable-Speed-Drives/Variable-Speed-Drive-CFW10-0.25hp-5hp


Is this what I need?

P.S. I am sure there are a lot of alternatives out there, cheaper, better, prettier to look at etc, but if I go ahead with this project it will be with the device offered to me here in my home town in New Zealand unless there is some compelling reason why it would be a really bad idea.

Thanks

dian
10-18-2013, 03:06 AM
i would make sure it has vector drive and capability to run a single phase motor (you might want to overdrive your drill press or something).

SGW
10-18-2013, 08:01 AM
It looks reasonable to me, although approx. $550 is more than you need to pay for a VFD. This one http://dealerselectric.com/item.asp?PID=4554&cID=0&scID=165 for example is $144, though it undoubtedly has fewer features than the one you are looking at. But that's up to you. I suspect almost any VFD of the proper size will suit your purpose, so go for it!

lakeside53
10-18-2013, 11:41 AM
He didn't say he was paying $550.... in NZ. Even in the USA that's just a fictional "list price".

The Weg's shown are just typical basic vfds. Sure it will work. But... look into the braking options. I didn't see any mention in their specs of a internal braking chopper to drive an external braking resistor. Having it built into the vfd is lot cheaper then buying and external dynamic braking unit.

rklopp
10-18-2013, 11:43 AM
i would make sure it has vector drive and capability to run a single phase motor (you might want to overdrive your drill press or something).
Say what? You don't need "vector" or "sensorless vector." Plain old "V/Hz" will do fine for home shop equipment. You don't need the capability to run a single phase motor, but likely you do need the ability to run from a single phase supply. In fact, I am aware of only one VFD that will run single phase motors, and it is very special, not available in the US except via special import from the UK.

The Artful Bodger
10-18-2013, 02:06 PM
Thanks for the comments.

It has connections for an external braking resistor, it would be considerably cheaper than US$550 and I would not want to spend US$100++ to get anything sent from the US.

John

MaxHeadRoom
10-18-2013, 03:35 PM
For CNC or equivalent I would certainly get a sensorless vector VFD.
Keep in mind that the typical commercial CNC induction spindle motor controller which is just a fancy version of the simple VFD have sensor feedback from motor shaft to drive, this enhances full control down to low RPM.
Sensorless vector is the next best thing, this is why you pay a little more for this version.
In the WEG line this would be the CFW-09, they make a nice VFD, I have used these in the past.
Max.

RWO
10-18-2013, 06:23 PM
Sensorless vector is a must. The cost is small but the performance increase is high at low freq. when you are slinging that big fly cutter or face mill. It minimizes the need to change belt position on a cone pulley mill to virtually never.

RWO

Mike Burch
10-18-2013, 08:23 PM
John, the specs for this VFD show a 230v 3-phase output, but 3-phase supplies in NZ are 415 volts. What voltage does the motor want, 230 or 415?
Cheers,
Mike.

The Artful Bodger
10-18-2013, 11:33 PM
Hi Mike, good point, I will make sure the motor can run 230V.

J Tiers
10-19-2013, 09:21 AM
Say what? You don't need "vector" or "sensorless vector." Plain old "V/Hz" will do fine for home shop equipment. You don't need the capability to run a single phase motor, but likely you do need the ability to run from a single phase supply.

Quite true..... but vector can be handy, even if you don't "need" it. You shouldn't expect to do all your speed change via VFD... belts are still useful.

And NO VFD will run a standard split phase motor unless the VFD is drastically over-sized for the power. They WILL run shaded-pole and motors with a single start-run capacitor and no centrifugal start switch("PFC" motors).



In fact, I am aware of only one VFD that will run single phase motors, and it is very special, not available in the US except via special import from the UK.

ABSOLUTELY NOT TRUE IN US. But the OP is in NZ.........

VFDs from Invertek, which is indeed a UK manufacturer, include several single phase output models. Invertek has active US distribution, and the single phase units are quite popular. (I know the guy who runs Invertek USA).

A number of US distributors sell Invertek.

I don't know about NZ, but as a country historically associated with the UK, I'd be surprised if UK products were unknown there.

Invertek is also widely sold by the folks who sell drives at a discount in the US.

Then also, MANY brands of drive are "bought-in" and not actually made by the seller, and Invertek is very active in manufacturing drives for other companies. I won't mention the names, but if you know what Invertek units look like, you can recognize them, despite different housing color, etc..

MaxHeadRoom
10-19-2013, 11:57 AM
In fact, I am aware of only one VFD that will run single phase motors, and it is very special, not available in the US except via special import from the UK.

One problem traditionally with running even cap run 1ph motors from VFD is the fact the phase angle for the split phase drops considerably as the frequency drops, often causing the motor to drop out of run at low RPM's, especially on load.
Max.

dian
10-19-2013, 01:44 PM
i have a "starvert" iC5 (SV008iC5-1F) made by LS Idustrial Systems Korea. it happyly runs the (one phase) drill press and grinder at doule speed. yes, it loses torque, but if you have a 2 mm drill, who cares? its also correct, you dont get any usefull low rpms out if it (using a big drill). i dont see, why they would not be distributred in the u.s?

Doozer
10-19-2013, 09:12 PM
I have received a ruling that provided I keep all my domestic chores up to date and performed to satisfaction I may convert my mill to 3 phase and VFD operation.:)



Grow some stones and rule your castle.
That is all.


--Doozer

J Tiers
10-19-2013, 10:38 PM
Grow some stones and rule your castle.
That is all.
--Doozer

These things are not a one-way street. Those who learn that are much happier in the long run.

Doozer
10-19-2013, 11:14 PM
I pity all you fools who have indentured your servitude to a woman.
All for what? Offspring? Or are you in it for the act?

--D

doctor demo
10-19-2013, 11:20 PM
Grow some stones and rule your castle.
That is all.


--Doozer

Maybe it is Her castle and He only has accommodations there in trade for "domestic chores" !

Steve

The Artful Bodger
10-20-2013, 12:10 AM
Dont fret yourselves boys I get more than I could have imagined in my wildest dreams from this arrangement!

https://encrypted-tbn2.gstatic.com/images?q=tbn:ANd9GcQfkWEoHLfzCq_zMQr0JQy011aL4KWXM 4hibBFBdNLBCOQVzE0jZw

JRouche
10-20-2013, 12:12 AM
I pity all you fools who have indentured your servitude to a woman.
All for what? Offspring? Or are you in it for the act?

--D

And I pity all "you fools" that haven't realized the woman in your life is prolly the best thing that HAS happened in your life :) Most friends I have talked to agree, our wives were a major reason for our success. And I'm successful. Ill never cut my wife out of that.

Now back to OP? I think that CFW10 unit will be just fine. It will do exactly what you want. But... You didnt say what wattage unit you scored? They have a few diff power supplies under that CFW10. For the 2HP 3Ph motor you should have the 5HP box. The 2200 watt box (5HP) will drive that 2hp motor just fine. JR

lakeside53
10-20-2013, 12:18 AM
For the 2HP 3Ph motor you should have the 5HP box. The 2200 watt box (5HP) will drive that 2hp motor just fine. JR


???? So.. what's wrong with a 2hp vfd for a 2hp motor?

J Tiers
10-20-2013, 12:23 AM
???? So.. what's wrong with a 2hp vfd for a 2hp motor?

Single phase input, presumably....

macona
10-20-2013, 12:54 AM
If the vfd is rated for single phase input, like most under 5hp are now, you dont need to derate.

The Artful Bodger
10-20-2013, 01:16 AM
I dont really know about 2hp or 5hp VFD but I will take the advice of the supplier as I will (if I go ahead with this project) buy the motor and VFD from the same supplier and compatibility will be a condition of purchase. The offered motor is a WEGT4000150B5.

J Tiers
10-20-2013, 09:45 AM
If the vfd is rated for single phase input, like most under 5hp are now, you dont need to derate.

Except for the ones that are not...............

lakeside53
10-20-2013, 11:29 AM
The original WEG link listed the relevant hp VFDS as single phase input with no derating.

J Tiers
10-20-2013, 01:40 PM
The original WEG link listed the relevant hp VFDS as single phase input with no derating.

Well, in that case no issue, eh?

But that is not necessarily a "general" or "blanket" situation for others who are not the OP and do not have the exact same unit.

JRouche
10-20-2013, 06:32 PM
Im solly, my bust. I assumed it was like the older units that needed to be derated for 1ph input. There I go steppin on my self again :) JR

PStechPaul
10-21-2013, 10:21 PM
I have a 2HP 230V Fuji/GE VFD that I bought new several years ago on eBay for about $65 and it has worked very well for several motors, and it will run on 220-240 VAC single phase. It also runs on 200-400 VDC which can come from a battery pack or an automotive inverter, in which case you could run your three phase machine shop on battery power and not worry about power outages. You can also maintain a pack of, say, 20 x 100 Ah Lead-Acid batteries for 240 VDC nominal and have 20 kWh of emergency three phase electrical power (which can be configured as 208/120 by providing a neutral).

I bought a 12V to 220VAC 1000W (probably a true 400W continuous) inverter for about $40 and it will power my VFD and a 2 HP motor (but I haven't pulled full power yet). I bought another which is rated 24 VDC in and 220 VAC out at 1500W, for $50, but it is probably about 800W continuous. I modified them to extract the internal 270 or 240 VDC which is used to create the "modified sine wave".

Here is a thread showing how I did it:
http://www.diyelectriccar.com/forums/showthread.php/modifying-automotive-inverter-dc-output-89691.html

Here is a video of the 12V inverter running the 2HP motor on my tractor project:


http://www.youtube.com/watch?v=kTsHYm5Y78U

And here is a video of me taking a ride on the contraption using a 24V to 300V DC-DC converter I designed and built myself (but it had some fatal flaws):

http://www.youtube.com/watch?v=j5TyhdY-cHQ

(can't embed more than 1 video)

JRouche
10-22-2013, 01:47 AM
Here is a thread showing how I did it:

Hey Paul. Love the vids and what you do for fun. Yup, even with the breaker tripping. You will get it figured out. Its your type of mind we need a lil more of here in the States. Its almost like we forgot to be inventors and tinkers like our predecessors were.

I do see some great ideas coming out of Australia and the inventors and tinkers there.

Keep working on it and posting. Im not the only one that enjoyed the two vids. JR