# Need Help VFD-Variable Frequency Drive



## nel2lar (May 1, 2017)

I am in the market for a VFD and would like a little help on just where to buy and reputation of the manufacture from some with experience in this area. I have a Millrite MVN powered by a Dayton 3 Phase, 2 hp, 3450 rpm on 208-220/440 volt power. But I have single phase service and have read how the VFD might just be what I need, help me out if you can.
Thanks
Nelson


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## GLCarlson (May 1, 2017)

VFD is pretty much the answer for low HP 3ph powered by 1ph service. 2 hp sizes usually want 220 single phase in. Take a look at Teco or WEG VFD's from Dealers Electric. There are others, but Teco has a good rep. Various choices, figure about 175-300 bucks for 2+hp. Dealers used to be best price around, haven't comparison shopped lately, so check that.


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## gld (May 1, 2017)

I've had one one these: https://www.driveswarehouse.com/wj200-015lf-2532 , for about 9 years. Would not be with out it now. Using it on the original motor that came on my Grizzly mill.


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## ninefinger (May 1, 2017)

I've bought twice from  http://dealerselectric.com/, first for my mill and second for my lathe.
The first was a GE / Fuji brand and works fine - even has bells and whistles like Modbus serial remote control capability.  The second was a very basic Teco model that does the job on the lathe.  I am satisfied with both.
You will need 220/240 single phase in as all the models I can find in 115 in only go up to 1hp.  
No need to oversize the drive though, get a 2HP and you'll be set.
Mike


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## Wizard69 (May 1, 2017)

At work we use all sorts of VFD's.  Frankly most of them are pretty good these days.   Personally I've been impressed with the Automation Direct line as being very good.     They seem to take all sorts of abuse including having the enclosure filled with 400 watts of RF energy when an RF cable burnt off.   Mind you this a rather hot machine cabinet in normal operation.


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## kvom (May 2, 2017)

I also have a VFD from Automation Direct powering my Bridgeport.  The fact that the company is only a couple of miles from my house is convenient.


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## nel2lar (May 2, 2017)

I want to thank all that have had a comment, good or bad. That was what I was looking for and I got it thanks to all of you. I made the purchased yesterday and now wait till it get here. I bought a 2.2KW 220V VARIABLE FREQUENCY DRIVE INVERTER VFD 3HP 10A,  220 volts single phase in and 208/240 three phase out. This is the unit I chose: http://www.ebay.com/itm/2-2KW-220V-VARIABLE-FREQUENCY-DRIVE-INVERTER-VFD-3HP-10A-/262955366802? Almost time to play.
Again thanks to all who helped.
Nelson


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## kvom (May 3, 2017)

A few thoughts.  First, you should use the start/stop buttons on the VFD panel to power the motor on/off.  Using the machine's switch can damage the drive.  On my machine I removed the switch and rewired.

Second, I remoted the switch panel via a cable.  The VFD lives in its own wall-mounted box safe from dust and swarf, while the panel is attached to the mill.

My panel has a rotary switch to control speed.  Not sure how yours works.


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## Niels Abildgaard (May 3, 2017)

kvom said:


> A few thoughts.  First, you should use the start/stop buttons on the VFD panel to power the motor on/off.  Using the machine's switch can damage the drive.  On my machine I removed the switch and rewired.
> 
> Second, I remoted the switch panel via a cable.  The VFD lives in its own wall-mounted box safe from dust and swarf, while the panel is attached to the mill.
> 
> My panel has a rotary switch to control speed.  Not sure how yours works.



Can You forward/reverse from the remoted panel without entering programing mode?


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## ninefinger (May 3, 2017)

I would say for the vast majorityof VFD's yes - you can reverse without programming.  You don't even need to remote the panel as long as you don't need to see the digital display for speed.
The VFD has input terminals for low voltage signals to control Forward / Reverse and variable speed.  
On my lathe I repurposed the original FWD/OFF/REVERSE switch to control those inputs and I can dial in the speed with the panel mounted pot.
On my CNC mill I've connected to these terminals from the PC (through a break out board) and the CNC program can control the spindle.  Before I got that going I had remote mounted a pot and switch to do as the lathe does.


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## Niels Abildgaard (May 4, 2017)

Thank You Ninefinger

My present set up is on picture.
3ph/3ph.
The control box was made by a deceased electrician and is full of relais.I asume it is to make no volt release .
I want to change to a modern single phase in /3ph out with a more sexy control panel and a flat cable connected remote like shown by Kvom .
If I ad a rev/off/forward switch will no volt release still be there?


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## xpylonracer (May 4, 2017)

Hi Ninefinger 

Can't see any ventilation slots or fan to cool the cabinet, better to keep some cooling air over the vfd, same applies to kvom, if the cabinet is dust tight seems it would also need forced ventilation via a filter.

Marcus


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## kvom (May 4, 2017)

Here's a photo of my setup"






VFD is in NEMA box mounted on the wall.  Control panel is on the arm alongside the DRO.  Note small box next to motor where original motor switch was removed.

This setup was installed in late 2008.  I did replace the control box when the plastic on the start and stop button wore through.


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## nel2lar (May 4, 2017)

Niels Abildgaard said:


> Can You forward/reverse from the remoted panel without entering programing mode?



Niels
I am going to use the 3 phase side to do my reversing, just swap two wires and done. I will be using a regular forward off reverse switch.
Thanks for all you do.
Nelson


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## nel2lar (May 4, 2017)

xpylonracer said:


> Hi Ninefinger
> 
> Can't see any ventilation slots or fan to cool the cabinet, better to keep some cooling air over the vfd, same applies to kvom, if the cabinet is dust tight seems it would also need forced ventilation via a filter.
> 
> Marcus



Marcus
I have thought about that and yes I'm going to have a fan run through the VFD.
Thanks
Nelson


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## Niels Abildgaard (May 4, 2017)

nel2lar said:


> Niels
> I am going to use the 3 phase side to do my reversing, just swap two wires and done. I will be using a regular forward off reverse switch.
> Thanks for all you do.
> Nelson



It is considered very bad taste to start/stop and reverse on the 3 phase side.
My converter (the blue thing ) has built in ventilator that only works when needed.
My main reason for  changing is a more  sexy look (old man buying Ferrari?) 
and earth fault problem connecting 3ph/3ph inverter.
Modern 1ph/3ph hopefully has not


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## MachineTom (May 4, 2017)

You can not flip the wires to reverse direction, with a VFD. In fact you should not turn off input power, until after the motor comes to a rest. Controlling the motor is all done electronically, low volt wiring 22awg size. If at top speed in fwd and you switch to reverse, motor will slow to stop and the accelerate to same speed in reverse. Soft start soft stop. It is selectable, but instant 3 phase start is not in the program.

While mills don't need much braking power,  as the rotating mass is low, lathes do need help slowing down, so there are multiple ways available to assist in run down. Depends on the model VFD etc.

Be sure the VFD is sized for single phase input, there is often a derating when a 2hp unit is run with single as opposed to 3 phase, an undersized unit will live a short life. Electronics like a VFD are not forgiving like contact points in a contactor etc. 

Both my Hitachi VFDs have been great, one now 11 years old the other 8.The SJ model with the detachable panel. They are both used with remote switching and control pots. Remote mounting the display so I can see it.


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## kvom (May 4, 2017)

I don't have a braking resistor on my mill, but if I were to do a lot of power tapping using just the VFD control I would want one.  That said, I do get some power faults using high RPMs (overspeed) when I hit the stop button.  At that point the motor just free spins and I can stop it with the spindle brake/lock lever.


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## ddmckee54 (May 5, 2017)

Kvom:

Check to see if your drive allows DC injection braking.  Drives that allow for external dynamic braking resistors will sometimes have this option.  This will give you some motor braking without the need for an external dynamic brake resistor, it applies a DC current to the motor.  You usually can apply a current of up to the motor's full load amps to help brake the rotating assembly.

Don


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## kvom (May 5, 2017)

I don't need braking in normal use, and if I did a braking resistor is less than $75.  The GS2 drive I use doesn't support the DC injection apparently.  A resistor would eliminate the overloads get occasionally, but when they happen I manually brake the spindle and do a stop/reset.


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## nel2lar (May 9, 2017)

Well I bought one from China and I am thrilled with it. The read out on the front panel goes from 0 to 400, Before I started it I dropped it to 50, that was not bad, I need to map it so I know what it is doing. This unit will go from forward to reverse and back. Ramps down then reverses and ramps up, smooth as they come. Now to learn the programming and set it up. attached is a pic of the unit, 3 hp, single phase in and 3 phase out.  I'm happy for now.
Nelson


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## ninefinger (May 10, 2017)

xpylonracer said:


> Hi Ninefinger
> 
> Can't see any ventilation slots or fan to cool the cabinet, better to keep some cooling air over the vfd, same applies to kvom, if the cabinet is dust tight seems it would also need forced ventilation via a filter.
> 
> Marcus



the lathe is operated manually and rarely gets a duty cycle of 20% (i don't work too fast). I've never felt it get hot or even very warm.

The mill, the VFD has a built in cooling fan that starts stops on its own, and I run it with the door open/ajar, its mounted on a wall away from the mill so low risk of chips, and it has a separate disconnect switch for when I'm done for the session.
Mike

edit - I should also mention the climate - both these machines are in my basement and stay within a few degrees of 20C or 68F.  even with the door closed on the mill VFD the steel box has enough cooling surface to cope, with the VFD taking care of its hotest components with the fan.  I could put in cooling vents but propping the door open is much easier.


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## ddmckee54 (May 17, 2017)

Ninefinger:

Keep the enclosure door closed, that or make sure that you periodically blow out the cooling fins on your VFD.  You'd be surprised how fast the crud and corruption builds up on them and then they cool no more.  I work with drives all the time and even in a relatively clean environment they will quickly build up a layer of crud if they don't breath filtered air or aren't cleaned regularly.

Don


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## Wizard69 (May 17, 2017)

ddmckee54 said:


> Ninefinger:
> 
> Keep the enclosure door closed, that or make sure that you periodically blow out the cooling fins on your VFD.  You'd be surprised how fast the crud and corruption builds up on them and then they cool no more.  I work with drives all the time and even in a relatively clean environment they will quickly build up a layer of crud if they don't breath filtered air or aren't cleaned regularly.
> 
> Don




Not to mention metal chips that fly about in a machine shop.  These can easily destroy anything electronic if they fall in the right place.


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## kvom (May 17, 2017)

As I stated previously, my VFD is enclosed in a NEMA box and only the keypad is near the mill.  8+ years with no hiccups.  One other thing I've done is to tape over any open electrical sockets that are close to flying swarf.


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## nel2lar (May 18, 2017)

Don
You can put the degree mark after the number just by holding the "alt" button down and type 248 on the keyboard, let go of "alt" key and wallah, the degree mark.   °
Nelson


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## xpylonracer (May 20, 2017)

Hi Don, doesn't work on my UK set keyboard, are you US based ?

Marcus


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## nel2lar (May 30, 2017)

Yes I an US based but the same system was used to set up the original computers. It is parts of the dos used for writing the old programs and not the computers are smart to use it by itself.
Nelson
Try both ALT keys


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## Cogsy (May 31, 2017)

I'm reasonably sure the 248 (or any of these types of codes) need to be entered on the number pad rather than the number keys along the top of the regular keyboard. It's a real hassle when using a netbook or similar.


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## nel2lar (May 31, 2017)

Yes it is the number key pad to the right side of the keyboard.   °   &#9787;  &#9792;  &#9689;  &#9688;  &#9632; Stuff like that hides under the ALT plus numbers. Some single digit work. &#9786; &#9787; &#9829; &#9830; &#9827; &#9824;  &#9688; &#9675;    1 through 9

Nelson


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## nel2lar (Jun 30, 2017)

Well the mill is up and running. The VFD was just as easy as wiring 110 v to anything. Love the ramp up to speed and ramp down to stop, forward to reverse without stopping first. And the variable speed make me feel like a real machine working. No belt, no wrench nothing to do but push a button. I will start to make plans to add a DC Brake soon.
Good to GO!
Nelson


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