Help with 2x72 build

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bigsig11010

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Jan 27, 2017
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I have a 2hp 3phase motor and a Mitsubishi D700 vfd. I need to find a switch with off/on with variable speed dial. Can anyone point me in a direction to find that kind of switch or if that’s not what I need I’m open to any advice.

Thanks.

BigSig
 
Tim, I don't think that will work. Also, we are not supposed to post sales links to non-BF sites.

Welcome bigsig. Fill out your profile so we know where you live and a bit about you.

I assume you want to put a remote speed control at the grinder.
I believe on your Mitsubishi the front panel disconnects and a ribbon cable is used to place it where you need it.
If that isn't the case, search "VFD remote control" on Amazon or Ebay you will find lots of what you want.

You can build one as well. Look at the manual for the VFD and see what the contacts are for connecting one. The parts are simple - a 10K variable resister, and a few switches. There are lots of YouTube videos and such on doing this.

Most manufacturers of VFDs make a plug-and-play remote for their unit. You could contact a supplier and see what they have.
 
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Looking closer at the vfd itself and the wiring instructions my question above is moot. All of the “switch” questions are right on the face of the vfd, ugh. So that gets me to my next issue which is that my motor has what my measuring says is a 1/2 inch arbor but my drive wheel is right at 1inch or the metric equivalent since the others in the set are metric holes. What kind of adapter do I need to mount the drive wheel on this motor. Or should I be looking for another drive wheel? I’m trying to add pics but can’t figure out how.
 
I never heard of a 2HP motor with a 1/2" shaft. What is the frame number/type - 56C? Those are 5/8" shafts, which is the size of most grinder drive wheels.

You will need to get a drive wheel that fits the shaft of the motor. Trying to shim it will likely not work well.
 
bigsig11010 said:
Still trying to add pics. Thought I could add an Imgur link but didn’t work.Pic motor. https://www.dropbox.com/scl/fi/t6aq...ey=a7jfazdwrass9tfn90ykd6rci&st=ylss50g5&dl=0

https://www.dropbox.com/scl/fi/3wpl...ey=t2059uzwi012k4fupc65ze41u&st=0jj94cw3&dl=0
Click to expand...
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
this is for USA,

What country are you in ? UK, Australia where you all have 400 vac service at home ?
 
Motor is 56C. That means a 5/8" shaft. You need a standard 5/8" drive wheel.

I'm afraid that VFD isn't going to work for you.
The VFD is model FR-D740- K, which is 400V3Ph in-out. That won't work unless you have 400VAC three phase power at your home. The Mitsubishi D700 model for 200V single phase in-200V 3ph out is is FR-D720S- K
You want a VFD that is for 240VAC single phase IN and 240VAC 3ph OUT.

Here is the Mitsubishi data sheet for te D700 series:
 
What everyone said above....
You need an accurate way of measuring. Calipers. Tape measure isn't accurate enough.
Metric equivalent isn't enough. If you need a metric bore, you need a metric bore.

If you need Imperial, then you need that.
High speeds will wobble and be off center, untrue. Dangerous.

In USA most people who are using low voltage are running single phase in, Three phase out.

I'm not familiar with that vfd, but find its manual online. You will need it's instructions if you are wanting to change it's parameters settings for remote usage.

Also if you have GFIC outlets, they don't play nice with vfd. Lots of people forget thst
 
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
this is for USA,

What country are you in ? UK, Australia where you all have 400 vac service at home ?
Click to expand...
I am in Alabama USA. I’ll look for data plate. It’s Mitsubishi D700
 
"Where do I go to update my profile here?"

You click on your name at the top right of the page.
Click Account Details.
Change or add the info and hit SAVE
 
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Yes the motor says 56C frame. So 5/8 drive shaft? I’m looking for a new drive wheel. What size drive wheel should I get ? Since it appears there are issues with this vfd do I absolutely have to have a vfd ? Can I just put an on off switch?
 
bigsig11010 said:
Yes the motor says 56C frame. So 5/8 drive shaft? I’m looking for a new drive wheel. What size drive wheel should I get ? Since it appears there are issues with this vfd do I absolutely have to have a vfd ? Can I just put an on off switch?
Click to expand...
You need a vfd to use that motor and I would not buy or build a grinder without variable speed

Get a six in ch dial caliper

91V2ZHk-wLL._AC_SL1500_.jpg
 
The drive wheel size is what determines the speed of the belt. The larger the drive wheel, the faster it goes. With a VFD the speed can be changed, so the drive wheel size is less important. Most folks use a 5" or 6" drive wheel.

The motor you have runs on 3-phase power. That is what the VFD provides. You can run a grinder on regular single phase power, but the motor must be a single phase motor.

To recap all the earlier info:
1) You really want a VFD running your grinder. It provides belt speed adjustment to run fast for hogging and slower speeds for finishing after hardening. The VFD needs to be rated for the power at your shop, which is usually single phase 220VAC.
2) The motor needs to be rated for the power output of the VFD. In your case, that would be 220V 3Ph. The motor and the VFD output must always match. Motor speeds come in (roughly) 1800RPM and 3600RPM. There are some technical reasons for choosing one or the other, but on a grinder with a VFD it does not matter much.
3) Drive wheel must match the motor shaft. Most grinders are run of a 56C frame motor, which has a 5/8" shaft.
4) Drive wheel size controls the belt speed. This is important on a fixed-speed grinder. On a grinder with a VFD, belt speed is variable, so a 5" or 6" drive wheel diameter is good.


Advice:
Unless you have all the knowledge, materials, and skills to build a grinder from scratch, buying a basic setup from a grinder manufacturer is wise. I highly recommend the Reeder Grinder Chassis Package. It runs $795 and has everything but the motor, VFD, and wheels. You should add the wheel kit for an additional $200.
That $975 plus a motor and VFD will set you up with a top notch flat platen grinder. They also sell contact wheels in all sizes. All their wheels are precision balanced.
Greg Reeder makes a great rolling bench that his grinders mount on. As with his grinders, it is all heavy aluminum and the bolts and inserts are hardened steel.
 
The ideal VFD is of course that KBAC even if it is $400 - or close to it anyway. Many of us prefer to use the Chinese VFDs, perhaps like this one listed on ebay - do a search for "126272221162", it's around $73 shipped. I've been using these for almost 15 yrs now and usually get 5 to 8 yrs life when used on grinders, lathes, etc. I do put a filter over the air inlets to reduce the amount of steel dust inside which will kill the VFD.

They are easy to setup and do give good service. The 2.2KW (3hp) gives a nice cushion to not overload the VFD.

Looking back I'm not sure anybody mentioned exactly why your VFD won't work for you. It says on the front panel it requires 3 ph, 380 to 480VAC input voltage. The output is just fine since the output is the same as your VFD with 380 to 480 3ph output. "IF" you happen to have 3 ph at 480vac, then your VFD won't work.

BTW, what part of Alabama are you in? I'm across the bay from Mobile, AL. If you're anywhere near here I'd be happy to help.
 
Thank you. I am in nw Alabama. About as far from mobile as you can get and still be in Alabama. Still trying to understand why this vfd won’t work. Need to understand that to know what to look for in another one. I need to make some notes on motor and get Mitsubishi D700 manual to compare contrast info
 
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