Trying to find reverse

grannyknot

Aluminum

Joined

Oct 18, 2015

• Nov 6, 2015

• #1

The motor that came with the 9C I just bought has had the data plate removed. The PO said he use to run it on 3 ph but changed to 1 ph years ago. It has no starting coil attached.
So it has 4 wires coming out of the coils, white, black,
green and orange. White/green and orange/black is how it came from PO and is the quietest and fastest starting of all of the combinations.
The combo of black/green with the white 120v wire and
white/orange with the black 120v wire is the only combo that will turn in the reverse direction if I get the shaft spinning in reverse before I apply power but it won't turn in reverse by itself. That combo is also kinda slow to get up to speed and is louder(not a good sound).
Does this sound like a motor that will reverse reliably?

 

K

kitno455

Titanium

Joined

Jul 9, 2010

Location

Virginia, USA

• Nov 6, 2015

• #2

looks like a repulsion start motor- Do the brushes lift off the commutator at speed? Those generally require the location of the brushes to be shifted to reverse- hence why you see that second set of elongated mounting holes in the brush holder.

allan

 

grannyknot

Aluminum

Joined

Oct 18, 2015

• Nov 6, 2015

• #3

Yes,the brushes do lift off once the centrifugal force pushes them away.
So are you saying that this motor will go into reverse but that I will have to physically move the bush holder over?

 

B

Big Gem

Aluminum

Joined

Oct 17, 2015

• Nov 6, 2015

• #4

It looks like that's the case. It's a great motor for high starting torques, but you seldom start a lathe under any load, so its great benefit isn't of much use. I've got a big one, and when I reverse it, the brushes are angled so that they would dig in if there was a rough spot or a piece of swarf in there. I use it on my jointer instead. I like capacitor start motors for lathes.

 

1

10KPete

Hot Rolled

Joined

Dec 21, 2008

Location

Nordland, WA

• Nov 6, 2015

• #5

It's been over 25 years but I believe that you do have to shift the brushes over one contact width. Armature
contact. You should double check me on that.

Pete

 

jim rozen

Diamond

Joined

Feb 26, 2004

Location

peekskill, NY

• Nov 7, 2015

• #6

10KPete said:

It's been over 25 years but I believe that you do have to shift the brushes over one contact width. Armature
contact. You should double check me on that.

Pete

Click to expand...

I think that's shown clearly in the third photo. Two sets of slots, with screws holding the brush holder
in one pair. Remove the screws, slide over the plate with the slots, and re-install the screws in the
other set of slots.

 

grannyknot

Aluminum

Joined

Oct 18, 2015

• Nov 7, 2015

• #7

Ok, so that isn't the best motor for the SB9, I swapped it over for the 1hp Leeson that has been slumming it as my grinder motor.
So this motor has a starter coil and 7 wires, P1 P2 T2 T3 T4 T5 T8
The Furnas drum switch has A 1 2 and B 3 4 in forward and A 1 4 and B 2 3 in reverse.
So going by the diagram on the data plate I have hooked up the wires like this,

Forward and reverse, white 120v wire goes from wall plug straight through to P1
A=P2/T3
1=empty
2=T8
B=T2/T4
3=black 120v
4=T5

T5 and T8 switch back and forth for forward and reverse.
I haven't turned on the power to this to this set up yet as I have never wired a switch like this before, I thought I would run it pass you guys first in case I'm not seeing some glaring error.
Am I ok to plug in?

 

K

kitno455

Titanium

Joined

Jul 9, 2010

Location

Virginia, USA

• Nov 7, 2015

• #8

Your description makes sense to me.

allan

 

grannyknot

Aluminum

Joined

Oct 18, 2015

• Nov 8, 2015

• #9

Got it going today, very smooth.
I haven't tried going straight from forward into reverse yet without letting it come to a stop yet but really I can't think of a situation where I would need that anyway.
Thanks for the help,
Chris

 

K

Ken-Bergen

Cast Iron

Joined

Jun 7, 2012

Location

Chilliwack BC Canada

• Nov 8, 2015

• #10

grannyknot said:

I haven't tried going straight from forward into reverse yet without letting it come to a stop yet but really I can't think of a situation where I would need that anyway.
Thanks for the help,
Chris

Click to expand...

It looks like a capacitor start motor so if you try reversing it at speed it'll keep going in the same direction.

 

F

FTF Engineering

Hot Rolled

Joined

Oct 30, 2003

Location

Philadelphia, PA

• Nov 8, 2015

• #11

Right. And the reason is because the start windings are switched out at speed and won't switch back in until the motor slows down enough to trip the contacts. If you switch from FWD to REV before the motor has slowed down enough to click the start windings back into the circuit, the motor will just happily keep humming along in the same direction. No damage, but no direction change.

Cap start induction motors will start and run either direction. It's the start winding that determines which way it will spin.