NEED motor advice I TOOK THE PLUNGE

H

hellgap

Joined
Dec 17, 2008
Messages
1,189
I bought a grinder today and need to know what type of motor I should get. I only have 110 and will up grade the panel to a 20 amp fuse so i can get up to a 1.5 hp with a 15 amp draw . I need to know what phase i need for in the future i want to get a variable speed control. Will a 1hp be enough ill be running a 3 step pulley.I will try to show the grinder i bought.
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I use a 1.5 HP 115 VAC TEFC Leeson farm duty motor. It is single phase and is rated to pull 17 amps on start up, but I do not think it pulls that much due to the fact that there is not much strain on the motor in a typical grinder set up like yours. This motor can be changed to 220 VAC single phase. Remember you will want a reversible or CCW (counter clockwise) motor.

I am using a 4 step pully and it runs great. I personally see no need for a 2 HP motor.
 
When the panel is upgraded ask to make sure you only have 110 capability. Almost all panels have 220 at the panel and it is a mater of breaker positioning and wiring to have a 220v outlet. To run variable speed you need a 3 ph motor. (or a DC motor and controller) Many VFDs convert regular 1 ph into 3 phase. But a 1 phase motor can not be used for varible spped. I have a VFD that converts 110v to 220 3ph, but, it will only run 1 hp. My 2 hp VFDs take 220v 1p input to make enough 3ph output to run a 2 hp motor.
 
Ok so what your saying is a single phase motor like what im looking at can not be used in conjunction with a variable speed controller. Only a 3 phase motor can be hooked up to a variable speedcontroler. I dont want to put 220 in my house when i wire my garage i will put in 220 every where . To run the single phase motor 110 ill just need a larger breaker. Then ill have to go buy another 1.5 3 phase and the dc variable speed controller. I have been told BALDOR is the best . One more thing will it yell me on the Tag that its Counter clock wise or do i wire it that way. Why do i need reverse rotation??
 
Will your grinder be in the same room as the Electrical Panel? Because if it is, having a 220 line wired is really a simple thing for even an apprentice electrician.

Patrice
 
Patrice I guess its not that big of a deal im 15 ft away from the fuse panel box im sure i have room for the 220 but would have to remove it when i wire the garage i only have 6 open spots and the 220 will take 2 spots correct. Ok guys give me both senario 220 and 110 what should i have if i go either way. It does make more sence to just wire in the 220.
 
If space in your panel is a problem they make what is called a Tandem breaker. And they make those in double pole also. All it means is that you can run two circuits in the same breaker as you would for one, or it is two breakers in one. If you can set it up to use the 220 volt you will be allot better off.
 
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This is a picture of a single pole tandem breaker. The picture explains it allot better than I did. These also come in douple pole which is what you would want for your grinder. Good luck with getting it set up.
 
Correct that you need a 3 ph motor for a VFD. Wade is also correct on the tandem breaker as a way to free up some extra slots in your panel. 2 tandems would give you 2 more free slots to put in a 220 breaker. You can get a good 3 ph TECF motor from http://grizzly.com/outlet/Motor-2-HP-3-Phase-3600-RPM-TEFC-230V-460V/G6243
For $110 plus shipping. A VFD for a 220v 1ph Input to run a 2hp 3ph motor for $177 from
http://dealerselectric.com/item.asp?cID=&PID=394.
This VFD isn't sealed. So you need to remote mount it and use a switch and a 10K ohm pot to control the speed and the direction. It isn't that hard to wire or program. I have 2 of them. If you want you can enclose it in a clear (so you can see the readout) plastic box with a couple places cut out and covered with filters for cooling air. I have all mine mounted up high on the wall, so I can see the frequency and have a 5 turn 10k pot and a dpdt sw in a small box by my machines. The sw turns on the motor and selects the direction of turn. The pot controls the speed. For the wires to the sw and the pot I use 6 conductor communication wire as it is low voltage and current. Then I have a piece of 4 conductor 16 gauge running from the motor to the VFD to power the motor. You can run a 2hp 3ph on 16 gauge as the amps are lower per leg of wire than a single phase which needs 20. Total cost around $500, with breakers, wire, motor, VFD, shipping, pot and switches. Subtract from that the cost of setting up your 1ph motor and that is what it would cost you to have variable speed. I like variably speed enough I have both my grinders (they share a VFD by a switch) and my milling machine set up with it. I have been running my disk grinder on a 1hp variable and am now setting it up as a combination grinder/buffer. It is the cats meow to go from barely moving to flying with the turn of a knob. Step pulleys are ok, Variable is GREAT.
 
I used a breaker like Wade posted. Just be careful though. The master electrician that came to check the setup told me that I had a good quality panel and that the tandem breakers were ok but that he would not recommend them with some of the lower end panels. Also, mine is wired externally, the wire being clipped to the wall, not inside it. It would be easier when you want to remove it later.

Patrice
 
I purchased 3 x 1 hp 90 Volt DC motors from Ebay a couple years ago. I ordered the dc controllers from BEEL.ca. Complete setup cost was less then $300.00 for 1 hp dc motor and reversible / variable controllers.

Dennis
 
Thanks guys i really dont know much about elecrical stuff. Ive never really wanted to do it cuzz getting electricuted scares the hell out of me. I de rather cut myself or hit my thumb with a hammer lol . I will get the 3 phase 220 reversable 1760 does anyone know what the model # is for the BALDOR motor. I have been told they are the best is there any others as good .I know Baldor is real expensive like 300 bucks here in canada. The Marathon is 179.oo at princess auto but i have to drive 50 miles to get it. So if i set it up with pulleys i want 1725 rpm ????? or 3450 ? ive heard the 3450 is way to fast. Ok so i guess im shopping for a 3 phase 1.5 hp DC with counter clock wise rotation is that it ??????
 
Who the heck is making that grinder? It looks like a super clean KMG clone. How's it put together, I don't see any bolts or welds?

Looks like a nice machine!

I think Rob is quickly becoming the Loveless of grinder builders. He came up with a good, solid design, and now everybody's copying it. :)
 
Nick this machine is being sold by the hundreds in france. The guy mills everything no welding zero its sand blasted anodized and powder coat painted. All the pieces are bolted together from underneath. It comes with a 1, 2 and 3 inch wheels 10 inch smooth contact wheel, glass backing platen , small wheel attachment. I had alot of help from alot of people and decided not to build my own and to find the best i could for a good price. very competative to say the least. kellyw
 
ANOTHER QUESTION what does RECONN mean for rotation thats what they say on the motors. kellyw
 
I think any 3ph motor will reverse. Just swap any two of the 3 inputs. With a VFD you can add a switch that will reverse the motor. The motor will also say high and low voltage on the wiring diagram. 220 is low voltage and 440 high. For most 220 3ph, you connect 4,5,6 together with no input, 1-7 together with an input, 2, 8 with an input and 3,9 with an input. If you get a 3ph motor you will need to get either a phase converter or a VFD as it will not run on household voltage as is. Don't spend money on a converter and step pulleys. By the time you do you will have spent as much as the VFD I pointed you to. I saw on the new customer sign up were you can put in providence and postal code instead of state and zip code so I think they do. With a VFD you can add a switch that will reverse the motor.
 
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Does this guy have a website and what do you mean by competitive? That's not a KMG clone, except for the bolting that's an exact replica.

Patrice
 
The best price you will find on motors is Princess Auto. Look for a farm duty motor. All the connection information for 110 and 220 are on the plate on the motor.

George
 
Hellgap,
What is your source for the grinder you chose? I am very interested in that grinder. Thanks for your help.
 
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