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Doc Nickel
10-22-2008, 07:11 PM
I'm about to put a VFD temporarily on my bandsaw, just to see if the motor works, and/or any bearings squeak, etc.

I'm still very new to 3-phase stuff, and previous times I've been able to go by already-paired wires or copying existing wiring.

Whoever unwired this saw motor, however, left off all the wire nuts, so I have nine loose wires, each with a little metal tag, numbered one through nine.

What's the proper way to pair these up? I have a diagram that someone posted here a while back, but I just want to double-check. It shows a "Wye" and a "Delta" configuration, and since I only have three connections on the VFD, I'm assuming I use the Delta; pairing 1-4-9, 2-5-7 and 3-6-8. Correct?

Doc.

lane
10-22-2008, 07:20 PM
Their should be a tag on the motor showing what wires tie to gether and what goes to line.

rockrat
10-22-2008, 07:48 PM
Had to take this photo 3 times to get it right. The flash kept putting a hot spot on the page. (Used my whiskey glass to difuse the flash a bit)

Click for larger photo.
http://i4.photobucket.com/albums/y128/katiecat222/ref/th_IMG_7271.jpg (http://i4.photobucket.com/albums/y128/katiecat222/ref/IMG_7271.jpg)

cheers!
rock

Crap! Too much whiskey. Made the darn thing go sideways.

kf2qd
10-22-2008, 08:41 PM
A three phase motor has each of its windings done in 2 sections - winding 1A & winding 1B in series is for the higher voltage and 1A & 1B in parallel is for the lower voltage (same way with winding 2A & 2B, 3A & 3B). If it runs the wrong way swap any 2 supply wires.

Swapping between Y & Delta offers a couple more options. but you can't always get at those other connections to change that configuration.

Doc Nickel
10-22-2008, 09:27 PM
Their should be a tag on the motor showing what wires tie to gether and what goes to line.

-No tag. Just a plate that gives the usual HP, speed and temp range. Nothing about wiring.

Rock- that's essentially the diagram I have, but I have to admit I don't yet truly understand it. The motor plate does say it's capable of 220v and 440v, so how does that affect how I wire this thing?

Sorry. What little I know about electricity is limited to knowing which is the bumpy and which is the smooth end of a flashlight battery. :D

Doc.

jmm360
10-22-2008, 09:29 PM
I'm assuming I use the Delta; pairing 1-4-9, 2-5-7 and 3-6-8. Correct?

Doc.

Nooo... You can sure use delta though wye seems much more common, and the picture a couple posts up shows correct hookups, you might print it for future reference.

A typical single speed 3ph has 6 windings and the ends of each winding are numbered, first winding has #'s 1 & 4, second has 2 & 5, etc. So you would never hook 1 to 4 or 2 to 5, that would just bypass that winding, if that helps to visualize it. (10,11,12 are tied internally in a 9 wire).

Regards,
John

wierdscience
10-22-2008, 09:36 PM
From memory mostly-

4,5,6 tie together and insulate.7&1,8&2,9&3 pair up and go to line.This is for 220v operation.

440v 4&7,5&8,6&9 pair off and insulate 1,2 and 3 go to line.

This is for a dual voltage 9 lead wye which will cover 80% of the industrial 3~ motors in NA.

More here-

http://www.firstelectricmotor.com/motor_connections.htm

Holycross
10-23-2008, 12:25 AM
Doc,

Have a look at this document. Shows the wiring options on motors and how to decipher a motor name plate.

http://www.egr.msu.edu/age/extension_outreach/TechNote103.pdf

Mark

Doc Nickel
10-23-2008, 05:40 AM
When in doubt, call an expert! :D

It's embarrasing I have such trouble grasping this sort of thing, but I've always been more mechanically than electrically inclined.

Anyway, a neighbor is a professional electrician, and she was happy to swing over to help out. We used the motor plate off the Master from my Nichols mill, which is a similar 9-wire style. She's familiar with 3~ stuff, so it's old hat to her, and she just had to explain one part of the diagram(s) and things fell into place for me.

Long story short, the Wells works great! The saw itself still needs some heavy TLC and a major cleaning, plus some replacement parts like the counterweighting spring, but we tried it on a chunk of 1-1/2" steel pipe, and it cut just fine and pretty darn straight. It tried to stall (blade in the cut, not the motor) a couple of times, but that's because there's way too much weight on the blade. I was trying to manually control it, but that's a heavy puppy.

Now that I actually understand the wiring a bit more- thanks in large part to to you guys as well as her patience- it'll be easy once I order up another VFD and wire this thing properly. (I've decided that'll be easier than trying to fab up a mount for a single-phase motor.)

Doc.

J Tiers
10-23-2008, 08:15 AM
Good you got it going.

For what it is worth, the wiring diagram is usually put onto the motor one of two places.

Sometimes it is on the actual data plate which is obvious and easy, but may wear off..

Sometimes it is under the cover of the wiring compartment, and may be covered up by a piece of foam or rubber that seals the cover. The rubber piece is generally not glued, so check under it to see if there is a diagram hiding.

Lew Hartswick
10-23-2008, 09:32 AM
When in doubt, call an expert! :D

It's embarrasing I have such trouble grasping this sort of thing, but I've always been more mechanically than electrically inclined.

Doc.
You shouldnt be embarrased at all. Just look at the conflicting info.
above gotten from the so-called "experts" on this board. :-(
...lew...

Doc Nickel
10-24-2008, 04:52 AM
True. But still...

Anyway, new question:

Last year, I parted out a several larger, professional quality treadmills. Two of them had these interesting "115V 3-phase" motors: whole thing (http://www.docsmachine.com/machineshop/tread05.jpg), closeup of nameplate (http://www.docsmachine.com/machineshop/tread06.jpg).

These motors have six input wires, similar to thes other 3-phase motors I've been dealing with (like the big grinder.)

Now, what do you experts think about maybe trying to run one of these- even just for test purposes- off of one of the VFDs I have?

Now, clearly the motor says 115v and the VFD is putting out 220. Probably not good, I'm guessing.

I don't "need" to use either of these motors, really, I'm just curious.

Doc.

ulav8r
10-26-2008, 08:47 PM
Doc, that looks similar to my motor that I am going to use on my heavy 10. The treadmill manufacturer (different than yours) advertises their treadmill as a 5 hp. Emersons spec sheet states that it produces 5 hp at 380V and 200Hz. The treadmill has 115V input and 1 horse VFD, so that is all it actually produces on the treadmill. I have a 240V, 2 horse VFD for mine but have not worked out all the correct settings yet, won't for a while.


True. But still...

Anyway, new question:

Last year, I parted out a several larger, professional quality treadmills. Two of them had these interesting "115V 3-phase" motors: whole thing (http://www.docsmachine.com/machineshop/tread05.jpg), closeup of nameplate (http://www.docsmachine.com/machineshop/tread06.jpg).

These motors have six input wires, similar to thes other 3-phase motors I've been dealing with (like the big grinder.)

Now, what do you experts think about maybe trying to run one of these- even just for test purposes- off of one of the VFDs I have?

Now, clearly the motor says 115v and the VFD is putting out 220. Probably not good, I'm guessing.

I don't "need" to use either of these motors, really, I'm just curious.

Doc.