which motor for this variable speed inverter (VFD)

SHOKR

SHOKR

Well-Known Member
i finally purchased a NWG, cost me about 8months salary (here salaries suck!) anyway i didnt buy the motor, but i did get this 2HP IP65, Taian, model: N2-202-M Inverter with Variable Speed.
img1047k (1).jpg

Clip.jpg
will buy the motor locally and i'm REALLY new at this:34:, need help deciding on motor specs, and sooner or later the connectivity :8:

thanks
 
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Hopefully your VFD is dust proof if niot it will need to be put in a proper enclosure. If metal grindings get into the VFD it may short out and ruin it. You will need a 3 phase motor that is TEFC (totally enclosed fan cooled) again the keep the metal grindings out. If the VFD can be set to run at double speed get an inverter rated TEFC 1800 rpm 2 hp motor and set the VFD to 2X. An 1800 rpm motor is a better motor and is designed to cool better at the slower speeds.
 
i really cant say i'm any less confused if not more!! i guess i need to get at this from another approach

locally motor rpms available are 900, 1400 and 3000, i was going to go for the 3000, or you think the 1400 would be better(incase the VFD can be set to 2x?)

will look into it

thanks Wayne
 
Maganinooo,

I've got a similar VFD set-up on my grinder and here's what I did -

instead of using the VFD to compensate for using a lower RPM motor I compensated for this with the pulleys I chose.

For example- If using a 3450 RPM motor then motor pulley to driveshaft pulley is a 1 to 1 ratio (or the same size, say 3" and 3" pulleys) to make the driveshaft spin at 3450 RPM

I'm using a 1725 RPM motor so I've got a 3" motor pulley and a 1 1/2" driveshaft pulley which also makes the driveshaft spin at 3450 RPM.


I don't remember the exact size pulleys I actually used but It works out that I'm actually spinning my driveshaft at more like 3600 RPM or just a touch faster than it would be with a 3450 RPM motor and the 1 to 1 ratio.

Hope this doesn't confuse you further. In simplest terms- use pulley sizes to compensate for a lower RPM motor. I'd go with the 1400 RPM out of those options.

Here's a link to a calculator to compare pulley sizes to help figure out which pulleys to get-
http://www.csgnetwork.com/pulleybeltcalc.html

With a 1400 RPM motor a 4.5" motor pulley and a 1.75" driveshaft pulley you would have 3599.4 RPM at the driveshaft which should be ideal.

Josh
 
Here's a pic of my homemade enclosure like Wayne mentioned-

Box built from scrap wood and two automotive air filters. Total cost $20

stagwipshop006.jpg


Josh
 
I would go with the 1400 rpm motor if it is rated to run at higher speeds. Check with the manufacturer.
Josh. Good Idea, the main thing is air volume, movement and filtering. Might need a fan to accomplish the air movement.
 
Josh Dabney said:
Maganinooo,

I've got a similar VFD set-up on my grinder and here's what I did -

instead of using the VFD to compensate for using a lower RPM motor I compensated for this with the pulleys I chose.

For example- If using a 3450 RPM motor then motor pulley to driveshaft pulley is a 1 to 1 ratio (or the same size, say 3" and 3" pulleys) to make the driveshaft spin at 3450 RPM

I'm using a 1725 RPM motor so I've got a 3" motor pulley and a 1 1/2" driveshaft pulley which also makes the driveshaft spin at 3450 RPM.


I don't remember the exact size pulleys I actually used but It works out that I'm actually spinning my driveshaft at more like 3600 RPM or just a touch faster than it would be with a 3450 RPM motor and the 1 to 1 ratio.

Hope this doesn't confuse you further. In simplest terms- use pulley sizes to compensate for a lower RPM motor. I'd go with the 1400 RPM out of those options.

Here's a link to a calculator to compare pulley sizes to help figure out which pulleys to get-
http://www.csgnetwork.com/pulleybeltcalc.html

With a 1400 RPM motor a 4.5" motor pulley and a 1.75" driveshaft pulley you would have 3599.4 RPM at the driveshaft which should be ideal.

Josh
Click to expand...

the pulley issue i understand and is easy really, its the electrical stuff that gives me googley eyes! so the 3000rpm motor generally wont have better quality over the 1400 ? like withstand heat, work better, etc. ?

also the more pressing question, the specs of the motor, i figured 3phase, 2hp, 1.5kw, anything else? (beside internal fan and self cooling?)
 
very cool enclosure, but that doesnt bother u when changing speed and such? like walking over to it, opening , etc. ?!
 
Wayne Coe said:
I would go with the 1400 rpm motor if it is rated to run at higher speeds. Check with the manufacturer.
Josh. Good Idea, the main thing is air volume, movement and filtering. Might need a fan to accomplish the air movement.
Click to expand...

that would be hard to check here, all i know there are like 3 motors in the market, chinese, italian, and bulgarian!! most sellers would say its the rpm is the fixed and MAX speed. be that true or not, difference between 1400 and 3000 is not that big, the 3000 is like $190 or so and the 1400 would be around $140

hope u dont mind guys why do u choose the 1400 specifically over the 3000?
 
Wayne Coe said:
Hopefully your VFD is dust proof if niot it will need to be put in a proper enclosure.
If metal grindings get into the VFD it may short out and ruin it.
Click to expand...

maganinooo states that his VFD is IP65
This is the metric equivalent of NEMA 4, Sealed against dust and liquid spray.
http://en.wikipedia.org/wiki/IP_Code

No need for homemade enclosures like on the TECO50 Nema 1.

For the motor I would look for
2 hp
3 phase
240 volt (220 )
Get an enclosure with a baseplate you can bolt down
Make sure that the shaft size matches the pulley that you can buy.

a 56 frame has a 5/8" shaft
a 143 frame has a 7/8" shaft

If you get your motor and pulley locally, you will have metric standards that I don' know about.
Do you research on what is available and buy the pulleys first

TENV Totally Enclosed Non Ventilated is the best type of motor "Inverter Duty"
It is made to handle the heat without the fan ventilation.

It gives better torque at low speed.
As you run a fan cooled motor, it gets less air at low speed and may overheat

(Source: Page 12 of the manuals for the KBAC-27D controller that Wayne sells
http://www.kbelectronics.com/manuals/kbac_manual.pdf)


They are not common and are more expensive when buying new.
If you can find one on ebay, It may be cheaper because people are searching for TEFC
...and I now just screwed myself out of any ebay motor deals on these....

TEFC is the most common and cheaper it will work fine because we are not putting a high torque load on the motor.

If you are building the NWG you have to use a pulleys anyway, buy the 1400 rpm moter and put the 3 step pulleys on it.
It will allow you to run the motor in the higher speed range (with better motor cooling and better torque) and step the speed down at the pulley.
 
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maganinooo,

Here's a shot of my grinding bench. The flexable conduit that comes from the right side of the VFD box goes to a small black box to the left of the KMG and houses the On/OFF/Reverse switch mounted on the top of the black box and the external potentiometer which is mounted on the front (verticle surface) of the black box. The digital readout on the VFD reads 0 to 60 (hertz) so You just turn the dial on the potentiometer till the VFD reads the desired setting and your good to go.

When grinding I don't need to move at all to access these controls. The VFD box stays closed all the time.

Wayne- It wouldn't be hard at all to add an internal fan to the VFD box. The VFD will shut itself down to protect from damage if it overheats so I figured if this happens I'll add a fan. It's commonly over 100 degrees in the shop during summer months and no problems with it yet even running full tilt hogging on a big stock removal Bowie.

I originally hard wired the VFD directly to the breaker box but decided to add a dryer outlet so I could power multiple grinders with one VFD. You can see I already added a disk grinder and hope to someday also get a horizontal to be mounted on the left side of the bench.

stagwipshop007.jpg


Josh
 
12345678910 said:
maganinooo states that his VFD is IP65
This is the metric equivalent of NEMA 4, Sealed against dust and liquid spray.
http://en.wikipedia.org/wiki/IP_Code

No need for homemade enclosures like on the TECO50 Nema 1.

For the motor I would look for
2 hp
3 phase
240 volt (220 )
Get an enclosure with a baseplate you can bolt down
Make sure that the shaft size matches the pulley that you can buy.

a 56 frame has a 5/8" shaft
a 143 frame has a 7/8" shaft

If you get your motor and pulley locally, you will have metric standards that I don' know about.
Do you research on what is available and buy the pulleys first

TENV Totally Enclosed Non Ventilated is the best type of motor "Inverter Duty"
It is made to handle the heat without the fan ventilation.

It gives better torque at low speed.
As you run a fan cooled motor, it gets less air at low speed and may overheat

(Source: Page 12 of the manuals for the KBAC-27D controller that Wayne sells
http://www.kbelectronics.com/manuals/kbac_manual.pdf)


They are not common and are more expensive when buying new.
If you can find one on ebay, It may be cheaper because people are searching for TEFC
...and I now just screwed myself out of any ebay motor deals on these....

TEFC is the most common and cheaper it will work fine because we are not putting a high torque load on the motor.

If you are building the NWG you have to use a pulleys anyway, buy the 1400 rpm moter and put the 3 step pulleys on it.
It will allow you to run the motor in the higher speed range (with better motor cooling and better torque) and step the speed down at the pulley.
Click to expand...

lol thanks, but ebay is not really an option, i could've gotten motor from the seller, but shipping would've killed me, so i'll check local market first

i already got the single step pulleys with the grinder, the reason i got the inverter is i wouldnt need the 3 step pulleys, but if its worth it i guess i'll buy them

but again no one is telling me why suggest the 1400rpm and not the 3000rpm? is it cost? power save? over heating? no NEED for it?

thanks 012345678910, as always right to the point :)
 
Josh Dabney said:
maganinooo,

Here's a shot of my grinding bench. The flexable conduit that comes from the right side of the VFD box goes to a small black box to the left of the KMG and houses the On/OFF/Reverse switch mounted on the top of the black box and the external potentiometer which is mounted on the front (verticle surface) of the black box. The digital readout on the VFD reads 0 to 60 (hertz) so You just turn the dial on the potentiometer till the VFD reads the desired setting and your good to go.

When grinding I don't need to move at all to access these controls. The VFD box stays closed all the time.

Wayne- It wouldn't be hard at all to add an internal fan to the VFD box. The VFD will shut itself down to protect from damage if it overheats so I figured if this happens I'll add a fan. It's commonly over 100 degrees in the shop during summer months and no problems with it yet even running full tilt hogging on a big stock removal Bowie.

I originally hard wired the VFD directly to the breaker box but decided to add a dryer outlet so I could power multiple grinders with one VFD. You can see I already added a disk grinder and hope to someday also get a horizontal to be mounted on the left side of the bench.

stagwipshop007.jpg


Josh
Click to expand...

o thats a very cool set up! specially like that u can use inverter for more than one motor! that should come in very handy in the future!

thanks Josh, will look for motor first thing in market and see what i'll do next

another question tho, how do u get it to reverse, and is that possible with any motor, and whats the usage really for that?
 
The switch is a 3 position switch. Push towards the wall = forward Center = OFF Pull towards user = reverse

I have used reverse with the belt grinder a couple times but could certainly live without that feateure for the BELT grinder as I've rarely had the need or desire for reverse.

The disc grinder is another story though. In using the disc to get bevels really FLAT it's a huge plus to have reverse so you can grind both sides of the blade edge up while the disc is turning towards the floor and throwing the dust towards the floor.

One side of the blade gets ground on the right side of the disc in forward
The other side gets ground on the left side of the disc in reverse.

If you didn't have reverse you would have to do all the grinding on one side of the disc and do one side of the blade edge down. Possible but NOT something I wanna do. If you tried to grind off the opposite side of the disc without reverse it would be throwing sparks and dust in your face.

It takes 3 wires to run 220 volt. Two 110 volt hot wires and a ground. Switching which terminal 2 of the 3 wires are connected to will reverse the motors rotation so it's a simple matter of wiring one side of the switch with the hot wires in one position and the other side of the switch with the hot wires reversed.

I figure even if I never used reverse it's not hurting anything wiring it this way so why not.

Any 220volt motors will work this way. 110volt motors will not unless they are DC motors which is a whole different subject, LOL.

Here's a link to how the wiring for the switch is done. Scroll down to "The Double Pole Double Throw switch" at the bottom of the page for an explanation.
http://www.1728.com/project2.htm

-Josh
 
thanks Josh, u sure do have lots of links about this :D

and u did actually answer all my questions! thanks!! for the time being i dont think i'll need reverse, but as u said wont hurt to have, and will make some of the work much easier or more comfy!!

PS: love the wire work in ur avatar, been looking for good wire work tutorial but never found any :|

on another note, whats good power for disc grinder motor? its luxury i cant afford now, but since it came up

thanks again Josh
 
Here's another link to some links for silver wire inlay tutorials, LOL
http://knifedogs.com/showthread.php?2980-Silver-wire-inlay-tutorial&highlight=silver+wire+tutorial

I got a 1 1/2 HP motor for my disc but only because it was deeply discounted from Grizzly tools. I'm pretty sure this is overkill for a disc motor and probably anything over 1/2 HP should be sufficient I would think.

spending money on tools is a seemingly endless proposition, LOL. No sooner than you get your newest addition up and running you realize the next tool you just gotta have, LOL.

Just thought I'd forwarn you

I got a drill press and demel then though ... if I only had a grinder
Then... if I only had a bandsaw
Then... if I only had a HT oven
Then... if I only had a bench vise and a "real" workbench
Then... If I had a disc grinder
Then anvil
then forge
and
and
and you get the idea.

Glad I could help. I did AOLT of research before making my grinder and motor VFD decisions and several others helped me out alot in figuring out a few things so happy I can at least pass along why I made the choices I did.

Let us know how you build turns out ! Josh
Then
 
thanks for the link

and yeah i know exactly what u mean, i started with small bench grinder and drill, now i want the belt grinder, and the drill press (or mini mill still cant decide) and i do have the long plan roughly laid, all depends on my performance and finances :D

thanks for the help! i do vouch ur paying some of ur education debts now lol

i'm actually buying used one, or bought... it should be on my way to meeeee :D
 
12345678910 said:
I say get the fast motor, you can always turn it down slower if you need to.
Click to expand...

yeah that was the plan! but everybody keeps telling me to get the med speed one, so i am bit confused now, i'm pro 3000rpm really, unless there is major set back to that or advantage to the 1400rpm
 
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