Help with 2x72 build

bigsig11010 said:
https://www.dropbox.com/scl/fi/2f34...ey=widu3axdcnrmopbqz0tn630ft&st=xsb9rkb3&dl=0 is this it? Could you explain a little more why this one won’t work.
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12345678910 said:
Motor looks good.

220v three phase is the normal.

Your vfd shows 400v three phase on the front
lets see the data plate and a link to the exact manual.

The vfd you want should be 220vac single phase input and 220 vac three phase output
this is for USA,

What country are you in ? UK, Australia where you all have 400 vac service at home ?
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p.jpeg

p.jpeg

That's the photo we needed to see.
I made that mistake once too, bought a good deal that no worky worky.

So to repeat
The vfd you want should be:
220 vac single phase input to match your wiring at home.
220 vac three phase output to match that motor

of course 220 could also be 240 same thing.

If you go with the ebay vfd, you will need a 240 volt outlet in your workshop
If you go with the KB model, you can plug into a normal 120 vac 15 or 20 amp outlet
Cost savings on electrical work install can be used on the KB vfd and allow you to plug into anywhere.
 
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"Will this one work" - Yes, it will work. It states single phase input and three phase output. However, it is for a max size 1HP motor. It won't run your 2HP motor.

"Still trying to understand why this vfd won’t work. Need to understand that to know what to look for in another one". - Yes you do. read on.

Ok, here is a basic explanation of how a VFD works:
A VFD is a Variable Frequency Device.
The VFD takes an input power and converts it to a variable frequency output. The input can be single-phase or three-phase. The device is input-output specific, and must be matched to the input and output voltage and phase of the supply line and the motor/device being controlled.
The output power is usually the same power level as the input voltage, but the output frequency can be varied from 1% of the input frequency to 400% of the input frequency. The output is three-phase.

You live in the USA where your frequency is 60 hertz. Your home power voltage is (nominal*) 115VAC and 230VAC. The home power is single-phase.

The VFD you have is 400V three-phase input and 400V three-phase variable frequency output. It will not run on 230VAC single phase.
You need a 230V single phase input and 230 three-phase output VFD. Some VFDs will run on 115VAC or 230VAC input. You have to make internal jumper changes to switch. If using a VFD on 115VAC the output maximum horsepower motor that it will run is reduced. AS 2HP motor will deliver around 1.5HP on a 115VAC input VFD. This is why you really want to run your VFD on 230VAC

For our knifemaking grinders, the gold standard VFD is the KBAC-27. It is 115/230VAC single phase input and 230VAC three phase output It is in a NEMA4 enclosure that keeps dust and moisture out. In a grinding shop, those are the main VFD killers. Cheaper VFDs often have open ventilation, no heat sink, that allow dust and moisture in, and less filtering then the KBAC unites. We set the parameters to 1-200% of the input frequency, which makes the grinder run from dead slow to twice as fast as the motor speed rating.

*footnote:
People use various numbers for their powerline voltage, Most are just the common terms used locally and not the exact voltage. 110/115/120 are all used synonymously to denote the standard US home voltage. 220/230/240 are all used to denote the upper voltage. Electrical devices will all operable within the range listed. If a device says 230V it runs on any voltage in the 220-240 range.
 
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edit: Looks like Stacy was posting while I was typing. He's got good info.
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NW Alabama? That's home - around Red Bay and Vina? Russellville?

Take a look at my post above, on your VFD it says "the front panel it requires 3 ph, 380 to 480VAC input voltage" Do you have 3ph power at your place? What power do you have at your place to drive the grinder with - 1ph 120 or 240 vac is normally what's available in homes.

Your motor is just fine, and your VFD will power your motor just fine, "IF" you have 3 ph, 460 vac power available. "IF" you have 3ph 460vac power available it will drive your motor just fine with NO VFD, except it will be single speed motor only.

For the VFD needed, the KBAC referenced above is a fine unit, unless you're on a budget (like me) in which case the Chinese VFD listed above, do an ebay search for item number "126272221162"
 
Moulton, Alabama. I know I have a 220 outlet but honestly I have no idea about 1 phase or 3 phase. I’m guessing I would have had to add something very extra for 3 phase and I don’t remember ever doing that. Built the house 20 plus years ago.
 
When I try to add a pic all I can get to work is adding the link why can’t I just add the pic like someone did above?
 
On your Dropbox page, right click the image and click Copy Image Link. On the BladeForums reply pane, click Insert Image. Paste the link in the window that pops up. It has to be a link directly to the image. The link has to be to the actual image file, not a dropbox/imgur/imageshack page that has the image on it. You can verify this by pasting the link in your browser window, and you should see just the image with nothing around it.
 
My computer skills are obviously lacking. It says “image can not be loaded from passed file.” I’m on an iPad so I don’t have a right click. I’ll try from desk top tomorrow if I get a break. Thanks again to everyone for the help
 
Moulton, Alabama? is that Jake's dragstrip around there? If so, been there many times back during the late mid 70s.

Yes, that last VFD should work, it's got the 1 ph 240vac input which is what you'll have at home. It puts out the required 3 ph 240 vac the motor requires. Looks like it's in 31 carts, is that ebay? Do you have an item number so we can look at the actual VFD specs? Do a google search on the ebay item number 126272221162 and you'll see a decent Chinese VFD for $73 shipped that will work and has a knob for speed control already installed.
 
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