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HELP: 115v Motor Wiring to Switch & Cord

holtzapffelFan

Aluminum
Joined
Dec 31, 2015
Gentlemen...Please help, so my husband doesn't want to tie me up with my power cord... (haha..)

The motor has 4 wire colors on the R/M Motor. It is 115v 2.1 amp 1/8 HP Single Phase, 1625 RPM.
Green / Yellow and this is assumed to be the ground wire - this seems pretty self explanatory - connect it under screw terminal to the motor.
Then a single Yellow, Red and Blue Wire. I want to attach the motor to the on/off switch.

I purchased an appliance power cord at Lowe's - something similar to this. I want to attach the cord to the switch.
https://www.lowes.com/pd/Southwire-9ft-16-3-SJTW-Power-Supply-Cord/5001797431

It has green, white and black wires. I *think* the black wire is hot. The green wire is the ground, the white wire is neutral.


I have not purchased a drum switch - so looking for recommendation if this is the only option. I would like to use an ordinary on/off power switch.... mounted in a silver box on top of my lathe's board. I have multiple ordinary household switches... I did buy a Leviton Switch, but the 2 screw construction is the same as an ordinary US household on/off switch. I don't know if I will find a drum switch without ordering from Amazon, MSC or McMaster Carr...

Referencing the motor label Does the Yellow "Line" on the motor label get connected to the Black? If the Black wire on the power cord is hot, then I need the switch to interrupt the power for the hot wires.
Why do I have red and blue wires? Is this to reverse the direction of the motor?

AND WHY ISN'T WIRE COLORS UNIVERSAL For all 115 v motors???? <Geez!>
I also have a 115v Dayton Motor... but same problem with 4 wires. I know this motor is reversible.

And which color wires do I connect the motor to an ordinary 2 screw(s) power switch. I bought Audel's Small electric Motors book by Rex Miller, the book does have electronic symbols in the appendix, but none of the symbols match this Robbins & Meyers label for instruction purposes.

I'm trying to 'do over" a piece of 1/8" steel for my bow drill from Rivett608 2021 class. Thanks in advance for your help.

Thanks - Tamra
 

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  • RM 115v motor label.jpg
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Why do I have red and blue wires? Is this to reverse the direction of the motor?

AND WHY ISN'T WIRE COLORS UNIVERSAL For all 115 v motors???? <Geez!>
I also have a 115v Dayton Motor... but same problem with 4 wires. I know this motor is reversible.

And which color wires do I connect the motor to an ordinary 2 screw(s) power switch. I bought Audel's Small electric Motors book by Rex Miller, the book does have electronic symbols in the appendix, but none of the symbols match this Robbins & Meyers label for instruction purposes.

I'm trying to 'do over" a piece of 1/8" steel for my bow drill from Rivett608 2021 class. Thanks in advance for your help.

Thanks - Tamra

I would assume you can get reverse. Is that desirable? The only time I use reverse is cutting left hand threads.

A global economy and standards all over. And wire colors all over the place. Woo is me.

The symbol for the switch in your picture is a on/off/on switch. Center position is motor off. Right and left is alternate direction.
Connect black to the center pole of the switch and white to yellow. I'm sure you can find a switch, even a cheap Dayton would do.
But try to do better than a Chinese copy.
 
Does this switch work? 3 screws on each side of the switch.

Assuming 3 screws for the motor side? and 3 screws for the power cord side?

And what do I do with the red and blue wires? I think all the electricians in the area are building a new building for Pfizer.


Thanks - Tamra
 

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  • Leviton Motor Switch.jpg
    Leviton Motor Switch.jpg
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Do you need to reverse the motor? If not a single pole switch with only 2 screw terminals will work. Green to ground on motor case. White to yellow on motor. Black to switch and black from other side of switch to motor for either forward or reverse. A light switch will do. A drum switch if you need to reverse motor. 1/8 hp motor seems weak for a lathe motor.
 
Thank you Rons and Deltap for the help... I like the ordinary household switch and will work on this ASAP and since my motor didn't come with a plug, I don't even know yet if it turns on. Yes it is a small HP motor, because it is a small benchtop Lathe. I found a fabulous SB Lathe on FB Marketplace, but Dear Husband shut me down because it was going to take more floorspace in the shop...


Samra
 
There is no way to get direction reversing with an ordinary 2-screw light switch. If that's OK, hook the Line to Red and the capacitor between Red and Blue; or for the other rotation direction, instead hook line to Blue, the capacitor not moving.

If you want reversing as well (I would for sure), there are two options:

Use two light switches, one 2-screw, the other 3-screw. The 2-screw controls power to the motor through the 3-screw switch. The 3-screw switch connects line to either Red or Blue. The capacitor is connected between Red and Blue, as before.

Go to an electronics store and buy a heavy (MIL-Spec looking) toggle On-Off-On 3-screw switch and wire according to the diagram on the motor. (This would be my choice.) Because you are controlling a motor, don't use a "3-amp" switch - not nearly heavy enough. Use the "Inductive" rating of the switch for motor loads. If no inductive load limit is specified, choose a different switch.

In the following, get the datasheet, and look at the SPDT options. If you choose screw terminals, you will need to attach terminals to stranded wire for reliable connection. What I usually use is blade terminals, or soldering.

https://www.mouser.com/ProductDetail/NKK-Switches/S303T?qs=U8XisqOR0Wd9kYb%2Bz%2BhY5w==
 
Thank you Rons and Deltap for the help... I like the ordinary household switch and will work on this ASAP and since my motor didn't come with a plug, I don't even know yet if it turns on. Yes it is a small HP motor, because it is a small benchtop Lathe. I found a fabulous SB Lathe on FB Marketplace, but Dear Husband shut me down because it was going to take more floorspace in the shop...


Samra

I would use a double bench approach. Bring the lathe into the house and rig up a system that enables the bench to be rigged for the lathe.
After using the lathe it is lowered into a cabinet (on rollers). The top of the cabinet now can have a sewing machine or whatever else you want.
 
I am working on a workbench for me; we cut down a really large trunk maple tree and I saved the bottom portion of the trunk and one branch. If I can find someone with a portable saw mill... I have green wood now.... will put a string on the tree soon, so I can talk.

I bought the Fine Woodworking workbench books...
I make my screws with dies while work is held in headstock by collets, but I don't ever use tap & die under power. Most of my work is by hand when it comes to using tap & die,

I have a 2nd lathe with ELS, and I just got it out to use it but it seems to want to be on vacation right now.


Tamra
 
QT: [It is 115v 2.1 amp 1/8 HP Single Phase,] * It should be fine with a simple household switch for one direction on/off.

Larger motors are best with a higher amp switch.

For larger motor devices like an air compressor, one should use the machine's on-off switch..not pulling the plug because doing that burns off the ground of the 3-plug and in time makes the machine unsafe.

It is not a bad idea to use a three-wire so to have an extra ground..even a single/extra wire going to a ground makes a safer machine.
 
Referencing the motor label Does the Yellow "Line" on the motor label get connected to the Black? If the Black wire on the power cord is hot, then I need the switch to interrupt the power for the hot wires.
Why do I have red and blue wires? Is this to reverse the direction of the motor?

This is a capacitor run motor. The yellow wire goes to the white (neutral) wire on your cord. The black wire goes to either the red or the blue wire, and the capacitor goes between the red and blue wires per the diagram. Moving the black wire from the red to the blue will reverse the motor direction. Your power switch interrupts the black wire.
 
For larger motor devices like an air compressor, one should use the machine's on-off switch..not pulling the plug because doing that burns off the ground of the 3-plug and in time makes the machine unsafe.

If you are getting an big arc off the green ground, something may be very wrong. Any idea how much current the green ground is carrying?

 
OP wants a mini Holtzapffel lathe. But not too many around.

I would love to buy any size Holtzapffel lathe, or the MADE Lathe...I don't have a spare $80k...If I could figure out the engineering - it is the ultimate machining project, but admit I would rather create a benchtop Holtzapffel with CNC Lathe and CNC Mill... terrible isn't it? But I think I have a better chance of making that lathe with a CNC then manually - but probably not enough experience.... it is always good to have lofty goals. I'll join the Plumier foundation....

I bought a little tester plug... to check the wiring... going to go play with some wires...

<edited> oops... the base price is $89k for the MADE Lathe - but of course you need all the accessories! I didn't even want to use Rivett608' Bergeon Tap & die in class, <deer in headlights> can't imagine standing in front of a Holtzapffel lathe and actually using it... I bought my own 0.8mm taps and dies from Germany, were delivered yesterday... if I break something tomorrow, I'm not breaking anything that can't be replaced.

Tamra
 
Does this switch work? 3 screws on each side of the switch.

Assuming 3 screws for the motor side? and 3 screws for the power cord side?

And what do I do with the red and blue wires? I think all the electricians in the area are building a new building for Pfizer.


Thanks - Tamra
that switch looks like a 3 pole single throw on off like for a 3 ph. circuit that's a lot of switch for that that circuit . but i do agree with rons being it only shows one rpm more then likely its cw and ccw and it looks like you have a run cap and if your only running it one way then lose the spdt on off on switch and go with a spst switch
 
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This is a capacitor run motor. The yellow wire goes to the white (neutral) wire on your cord. The black wire goes to either the red or the blue wire, and the capacitor goes between the red and blue wires per the diagram. Moving the black wire from the red to the blue will reverse the motor direction. Your power switch interrupts the black wire.

I don't think there is capacitor mounted on this motor. I've looked at all the motors in our shop and capacitors are very visible, but even my Jet Mini wood lathe doesn't have a capacitor on its motor and the bed on that one is x2 larger then this lathe. Our 12" antique delta disc sander (excellent piece of equipment) has a capacitor on it.

Looking at the shaft, clockwise or counter clockwise, whichever wire is, as an example Red = CW, and Blue is CCW, (it is one or the other) then the last wire is left with a wirecap in the electrical box?


Happy Labor Day to all...

Tamra

Screenshot 2021-09-06 104535.jpg
 
Read the label you posted. It's supposed to have a 25 mfd run capacitor between the red and blue wires. That's the thing
(poorly drawn diagram...) in the circle, two parallel plates.

Between the red and blue wires.
 
that switch looks like a 3 pole single throw on off like for a 3 ph. circuit that's a lot of switch for that that circuit . but i do agree with rons being it only shows one rpm more then likely its cw and ccw and it looks like you have a run cap and if your only running it one way then lose the spdt on off on switch and go with a spst switch

yup there's a run cap . this is child's play all the info is there just test wire it up on a bench with a cap and cord and a few wire nuts as mike hadeck would say it ain't no big deal
 








 
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