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Change rotation on dual speed 115v motor

6K views 27 replies 10 participants last post by  carmusic 
#1 ·
Got sent here from electriciantalk.com. This is my first post here and I'm hoping someone can help me out...
I came across an add on CL for 2 pool pumps. Went and looked at them and they both worked pretty good and I got them for $20 each. All I wanted was the motors from them because I can always use the motors for some other purpose. I have a cheap HF drill press so first idea was to swap out the 1/3 hp motor it came with for the smaller of the two that has 1-1/8hp
. I took it all apart, bolted the motor on and wired it all in only to find out it spins in the wrong direction.
I've spent the last day looking over wiring diagrams and reading post after post on different forums but none of them seem to cover a dual speed setup like this.
So my question is, what wires do I need to swap to reverse the direction of this motor? Its a Franklin Electric motor 115v, dual speed, single phase. I tried to take it into the local motor shop but they are closed until monday out on a "service call". So I came home and took the motor apart because I'm impatient with this type of thing. It actually came apart pretty easily and it doesn't seem to be in bad shape at all for a motor of unknown age. Both the bearings are good and the wires are still flexible and no corrosion.
Thought about just flipping the motor upside down and held it up there to see how it could be done but, I honestly thought it looked real hokey and didn't like it. Plus it would make it real top heavy.
It doesn't say anywhere on the tags that it is reversible and it has no open leads on the inside. Also without any labels on the wires, I do not know which ones are 5 & 8 to try that which I have read on many different forums. Thats why I'm trying to find someone on here that can look at the pics and tell me what wires to swap. Only markings that I can find are where the power cord connections go and they are "line 1" "High line" "low line".
Spent about a 1/2 hour looking at the franklin electric website yesterday with little results and searching the model # on the site only gets me this:
"Your search - 4105030400 - did not match any documents.
No pages were found containing "4105030400"
I have found other Franklin diagrams but non match my motor exactly as far as wire color and setup.
Here is some pics







And no, I'm not buying all new LH bits...
 
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#2 ·
I suspect your SOL.

Single phase motors run in one direction only unless it's wired for fwd/rev operation. The name plate will usually show it.

And, no, swapping the hot and neut will not change the direction.
 
#7 ·
Yep.

That will change the phase relationship between the start and run windings, and it'll turn the opposite direction.

The run windings on a single phase motor are bi-directional; they don't care which way the rotor turns. The sole purpose of the start winding is to provide a phase shift in one direction or the other. Without the start winding, the rotor doesn't know which way to begin turning.

So if you change the location of the ends of the start winding relative to the run winding, the rotor will turn in the opposite direction. And since the white (or gray....) and blue are the ends of the start winding, swapping them will make it turn the other direction.

Rob
 
#10 ·
OK I just realized this is a two speed motor. There should be three windings, high run, lo run and start. You need to identify the start winding and reverse the leads on it. The start winding will be the one connected to the centrifugal switch that disconnects when up to speed.
The start switch is the bits where the two orange wires are connected.
 
#11 ·
As noted, there are 3 windings in this motor. We need to find the start winding, the other two are run windings.

It's obvious that blue is not one end of the start winding.

One way to know for sure is to take the capacitor cover off, and disconnect the lead that goes to the stator (winding). When you get the cover off, short the capacitor terminals together with a screwdriver. A capacitor can hold a charge for a long time, and getting blasted with it is not fun!

Connect one lead of a meter set to read continuity (Ω) to the white lead that goes to the stator. Make sure it doesn't touch anything.

Now, find the lead that reads nearly 0 Ohms. Be sure it's disconnected, or you'll read back through the other windings. Check all other wires that you can. They should read open.

I suspect it'll be the black one. Blue is very likely the common of the high and low run windings.

When you find the one that reads continuity to the white lead, swap that lead with the gray one that lands on the terminal board, and re-connect the white lead to the capacitor terminal.

Rob
 
#13 ·
Yes it does matter that yellow and black share the same terminal.

Looking at both endbell pics, it appeared that yellow is on the end terminal (low speed) and black is on the center terminal (high speed).

Since they are on the same terminal, we don't want to change the polarity of the start winding, we want to change the high speed winding.

To do so, we would need to isolate each of the run windings. Since there are 5 wires coming from the stator, this would involve cutting open the string and paper where the orange and brown wires go into the stator, and un-splicing the ends of the high and low speed windings.

I really don't recommend doing this, mainly because it's nearly impossible to not nick the varnish from the winding wire. If it gets nicked, two or more of the coil turns will very likely short together. This will result in more current than the winding wire can handle, and it'll eventually burn up even with no load at the shaft.

A motor shop would be able to do this, because they can bake new varnish onto the windings, but it'll cost more than the motor is worth.

Rob

P.S. We did indeed change the polarity of the start winding by swapping the gray with blue, but since it is in parallel with the low speed winding, the net result was a fight between the high and low windings. High wanted to go one way, low the other. Hence the loud hum.......
 
#16 ·
The only way I can see would be to try to reverse install the commutator. Swap the end cap with the commutator 180 degrees.
You would have to mark each wire and extend them to the other end of the motor. the big question is will the windings allow the commutator to be reversed and still spin.
 
#15 ·
Unfortunately, this motor uses the high speed winding and the start winding to start whether it runs high or low.

One of the centrifugal switches cuts out the start winding (the one with the blue wire), and the other energizes the high speed winding during starting, then switches to low speed if that terminal is energized.
 
#17 ·
I might go out and try swapping the ends. I saw a video about doing that so I might as well give it a shot. I have lots of wire and terminals to extend them. But, if that doesn't work I think I'm going to fab up a motor bracket and just flip the motor upside down to be done with this. Thanks for all the help guys!
 
#19 ·
I did that by disconnecting the cap but I really don't want to have to start my drill press by spinning it by hand. I've spend some time today fab'n up a new mount to invert the motor. Depending on how the final outcome is, I may just keep it this way.
 
#23 · (Edited)
Spent a few hours yesterday making a new mount to flip the motor and it was all for nothing. All went well up until the test run when I found out the motors output wasn't very much stronger then the crappy HF motor that came with the drill press. On the test run, the motor stalled out trying to drill into 1/8'' steel with a 3/8'' bit. which was the whole purpose of doing the upgrade in the first place. So it looks like I'm going back to the drawing board for this one.
Thank you guys for all the help. I'm sure I'll be back with a few more questions.
 
#26 ·
Look at the motor nameplate. It lists the FLA as 11.6- 2.5

If you reduce the amperage when you go to low speed, you are reducing the HP. It is no longer producing the 1.125 HP. My guestimate is you were getting something slightly less than 1/3 HP.

Sounds like an above ground pool/spa motor.

Either run the thing at high speed and use intermediate gearing to slow the speed down to your desired rpm, or get another motor.
 
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