# This Should Be Way Easier Than I Am Making It- Furnas L-143 To Craftsman 115v Single Phase Wiring.



## ChattyMatty (Nov 2, 2015)

The more I look around the net, the more confused I get. What I've got : 
1955 Craftsman Single phase 1/2hp motor.





with red, green, and tucked in there is a dark blue in addition to the two yellow leads from the capacitor. This was a model with a power switch, which I've eliminated, but no biggie, just the tow power leads down underneath now.

And this NOS Furnas L-143 reversing switch:




with red, black, brown and white leads.

But I tell you what, every diagram I look at, seems to want to tell me something different. My gut tells two of the leads (prolly the black and the red) would just go to the power leads) and the the other two... dunno some diagrams seem to tell me to run another lead back to the switch other just seem to want a jumper at the motor.

Anyone been here before?


----------



## GaryLa (Nov 2, 2015)

I just re-wired one of those yesterday!

Although someone before me had already messed with the wiring and reduced it to two wires. (I added back earth ground).

I don't know why it has four leads, but I will tell you that the wiring's insulation is likely in really bad shape. Under the nameplate band in the "rear" at the mount the wires leave the motor and bend around the sheet metal of the plate. Mine were very frayed and would've been fine if I hadn't touched them at all. But having to add a cord, I moved them around a bit and could see they were going to fray and short out. The insulation on mine was so dried out that it practically fell off.

Your switch is more complicated than mine. I would imagine yours is for the sake of reversing. Try ohm-ing out the leads. You can ID which pairs are which by ringing them out. I had only the 1 pair which was reading at 1.6 Ohms.


----------



## mzayd3 (Nov 2, 2015)

Well, pictures of the motor and switch are nice. But it would helpful if you took pictures of the wiring diagrams that are on the motor and switch.  If you had those, we could certainly give more direct help.


----------



## ChattyMatty (Nov 2, 2015)

Therein lies the rub- nothing more on the mother than "reverse the yellow wires to reverse direction" and noting in or on the switch. I was assuming this would be the one- but looking at the motor it leads (pardon the pun) me to believe that doing ti this way all I will have managed to do is connect the capacitor to leads 1 and 3? I suppose it could really be that simple, but my gut wants me to leave the capacitor connected to the windings independent of which way the motor is being powered, and the switch (1 and 3) to either the red, green or blue leads or to the terminal board... or something. But maybe it is just 'run the capacitor through the switch?"


----------



## Bill C. (Nov 2, 2015)

When you get it figured out use some colored electric tape and mark what each lead does.  Good luck


----------



## ChattyMatty (Nov 2, 2015)

Yeah, getting there. It functions when wired as per that diagram- the switch breaks down to:
1-brown
2-red
3-white
4-black
but function is a loose description. Only operates one direction, is OFF in either FOR or REV positions and removing the handle to allow for rotating past the stop on top allows for operation just past FOR (so technically would be a fourth position on the switch) but rotates the same direction as before. I suppose I should keep rotating it to see it it ever reverses I guess.


----------



## middle.road (Nov 3, 2015)

I have a similar motor on my Logan. I'll check and see if there's anything on it that might help.

Here's the parts list, no wiring diagram though. Don't it figure?
http://vintagemachinery.org/pubs/222/3331.pdf

Love the style of the Furnas Switch. Going to have to find one of those. 
My Father worked for Furnas for years and I never saw one like that.


----------



## ChattyMatty (Nov 3, 2015)

Yeah, when I saw the switch I had to have it... the 'correct' one for the 618 is rather clunkly on that giant cast iron arm, and even the 'normal' one for the 10/12 didn't look as easily as adaptable. This has been a long slow build (I thought my bicycles were expensive lol) but the long and the short of it is the Atlas legs I picked up just don't put it at a comfortable work height for me, so I'm going to eventually pick up a set of 10" feet, set those on the legs on one maple shelf and add a second tier for my 6"... essentially as if someone unbolted the lays from their 42" 10F, left the feet on the plank, and bolted the plank and 618 lathe on top of them. I figure that'll give me about 4" more height, and to get to an actual relevant point, I'll inset the switch into the bottom of the left foot where it's easy to access but low enough that the gear door will swing open. There is another with the same part number I saw with a flat base and a nut welded on, but I don't know if that was a shop mod. This one still had the original price tag 




Looks like it's just time to borrow the voltage tester from dad and see which connections are actually being made inside the switch. Lazy me wanted plug and play after 60+ years ha!

But he's getting there- got his final home all rewired with a dedicated/switched 15a circuit (overkill, but whatever, finding an unused breaker in 60 year old garage wiring? Priceless) with nice LED illumination, some Schwinning inspiration, add another few hundred bucks and he's good to go 



(weak sewing machine motor is going away and I have some nice planking I suspect was salvaged from a bowling alley for the tops... prolly gunna hack out that cabinet too.)


----------



## ChattyMatty (Nov 3, 2015)

Alrighty, Houston, we have liftoff. Turns out the wiring diagram above is correct, it just would have made I little more sense to me I suppose if the purpose of what we are trying to accomplish with the switch were explained... that is what was hanging me up. I was too worried about what the coils were doing. Then that one little tidbit of info that had been staring me in the face the whole time hit me "To reverse the direction, swap the yellow wires." That's really all the switch does here, provides power to the coils no matter what, and simply flips which yellow wire from the condenser is connected either to to the hot lead or the comm lead from the power cord. So, the only thing I needed to make sure was that the contacts were in fact connected 1-2-3/4-5-6 as in the diagram, so off comes the cover-



Just look at those sexy new contacts!




A quick continuity check shows they are clumped together and not criss-crossed for some stupid reason, and if you notice, they even mark one contact as the center of each circuit by making it a little smaller than the adjacent two.




I've removed the power cord for simplicity here, but below 11 and 5 terminals are the condenser wires and 2 and 7 are the coil wires (previously these were the wires which powered the motor):




so basically you just clock the rotor around until the "off" position adjacent to one of the power leads, such that rotating it clockwise connects one circuit to the hot lead and the other to comm, then double check to make sure you have one of each type on each circuit, a condenser wire and a coil wire. Rotate counter clockwise back through "off" and into "on" again and this time the circuits should  grab the other condenser wire but the same coil wire (which one doesn't matter). In my case one of the terminals was a little loose for my taste and I happened to have a silicon o-ring the right size (the electrical tape you see in the last pic was just too stiff) to apply a little spring pressure inward for nice solid contact.

When it's time to re-assemble, flip the whole thing over and paying attention to the two small dimples in the side of the cap and the position of the screws in the base, find a position which allows for "off" to be centered between the two posts and arrange the badge where you want it (outward in my case).




After all this fidgeting, the cardboard insulation which locks the Bakelite part of the switch in place and keeps it from rotating was getting a little polished allowing the switch to turn in the cap rather than move completely into the FOR position, so a little white glue to lock it in place and it's good to go, working in FOR and REV, and more importantly, OFF


----------



## mattthemuppet2 (Nov 5, 2015)

well done! I was planning on chiming in to explain how it works, but you've already fixed it 

Simple principle for all FWD/REV switches - + and - AC wires coming in (A+B), 2 run winding wires going out (1+3) and 2 start winding wires going out (2+4 I'd guess). To reverse, you wait for the centrifugal switch to close and then swap the start winding wires from 1 incoming AC pole to the other one.


----------



## ChattyMatty (Nov 7, 2015)

Yeah, that's where I was also getting confused- kept seeing the references to "start winding" or "start wires" and didn't realize these were synonymous with the condenser wires.  AC of course doesn't care about polarity (otherwise all one would have to do is turn the plug over in the outlet), but as far as the motor is concerned it does care about the polarity of the _condenser _which is what is being flipped by the switch_. _Hence why the motor must be allowed to come to a complete stop before reversing- moving through off and into the other direction with it still spinning resupplies power but the motor continues in the direction of current rotation. As luck would have it, he 50/50 shot of direction of rotation matching the way I wired it (FOR being forward not reverse) even came out right the first time.

Happy camper


----------



## rac1812 (Apr 9, 2018)

Hey it works....... first time....... in the correct rotation......  with out blowing the breaker.........but I am having a ***** of a time closing the switch cover.
Now that I know it works I may have to see if I can squeeze all the 6 wires inside that tiny, very small, little switch cup.....

Thanks  for all the help.

Bob C


----------



## markba633csi (Apr 9, 2018)

A little clarification:  "start winding" or "start wires"  usually means "start leg" which is the start winding, the capacitor, and the centrifugal switch all strung together in series with two leads brought out.
The motor can be reversed by swapping either the start leg or the run winding(s)-  either will reverse the motor
Mark


----------

