Switch wiring - Jet 8 X 18 mill

[yellow_cad]

Re: Capacitor questions

Yellow_cad Do you have one or 2 capicators on each motor or 1? Is the motor rated for 50Hz or 60Hz? The can type is not important though the can is a better Capicator construction shouldn't make a difference now. Simply put the capicator creates a phase change. I'm sure you have seen the typical sine wave similar to a backwards s on it side. That is the Voltage plotted to time. To shift the phase means that for any given interval in time the voltage is different, this diffrence is measured in degrees. So if I were to plot two same voltages that were 180 degress shifted it with look similar to an S and the backward S written in the same space and look like an 8 sideways. When a single phase motor is started it has no idea which way to spin so it usually don't. Spinning causes a counter emf (electro motive force) that's opposit to the input voltage and loweres the current. So if the motor doesn't rotate the winding will eventually burn up. To get the motor to start rotating a start winding is required because the coils get the change in voltage though oposite at exactly the same time the rotor does not know which was to turn. If you now plot the start voltage it would look like the sideways 8 with the side ways s starting in the middle of the o of the side ways 8. This shift will cause the rotor to move as it will be at max. when the others are at 0. In shaded pole motors a capicator is not required. In the capicator start motor a capicator is used to created the necessary phase change needed to get the motor to start, to change the direction the capitator is connected to the other side of the line. Though 115VAC motors use a Neutral the motor sees it as a power source and electically the two inputs are 180 degrees out of phase with each other the Capicators will cause a 90 degree shift in the start winding so that the motor will begin to rotate. In a single capicator motor the Capicator is switched off. Understand?
To understand your motor I need more info. Can you post a connection diagram? Where the motor is made is not important unless it's 50Hz as many other countries use 50Hz not 60Hz. You can't compare a 1/4 Hp motor to a 1Hp 2 speed motor. When you say work at low speed, will it try to start at high. Have you tried to start it with any belts removed? Have you tried getting the motor spinning at low and switch to high fast while it's still spinning?
Frank

Each motor has one capacitor and both motor plates state 60 Hz. I have a PDF file of a short document that contains the wiring diagram and the connection diagram for the motors, switch, capacitors, and power. The thing is, I'm not sure how to get that on a post. I have looked all over the site and don't see a way to do it.

 

[yellow_cad]

Re: Capacitor questions

Each motor has one capacitor and both motor plates state 60 Hz. I have a PDF file of a short document that contains the wiring diagram and the connection diagram for the motors, switch, capacitors, and power. The thing is, I'm not sure how to get that on a post. I have looked all over the site and don't see a way to do it.

MODEL 818 BENCH LATHE.pdf (1.43 MB)

Not sure, but maybe I got it uploaded. It's pages 18 and 19 of the document.

 

[yellow_cad]

Re: Capacitor questions

Was able to open the attached file. I see the motor connection, it's a connection diagram so I'll have to redraw it. What's the function of the switches? I assume the red button is not connected to a switch but re-sets all the others. I assume it's the "Off or Stop". There is 2 black buttons and a long black button plus a white button. Looks like the white button controls the mill motor. I'm thinking one small black button is high speed , the other low and the long black button is lathe motor "On or Start". Am I correct?
Frank

Did you see both diagrams (pages 18 and 19)? Page 18 is a wiring diagram and page 19 is a connection diagram. The basics are that the red button turns both motors off. The white turns the mill on and the two single blacks turn the lathe on either in forward or reverse. Past that, I am only guessing since there were no instructions on switch operation. It looks like you push a single black whether you want to go in forward or reverse while at the same time pushing the long (double) black button. The switch will work this way but I don't get the desired results so maybe that is not how the switch is supposed to work. I was hoping that someone would know how the switch was supposed to work (for two speed operation) by seeing the diagrams. By pushing the forward or reverse single black button, the lathe is going correctly in the low speed mode. My problem is getting the lathe to operate in the high speed mode. When I push one single (f or r) while pushing the long black button, the lathe goes at about half of slow speed and the lathe motor soon starts to smoke. Jim

 

[yellow_cad]

Re: Capacitor questions

So I can understand exactly what you are saying, please give me your suggested procedure for pressing buttons to:

go forward low speed

go reverse low speed

go forward high speed

go reverse high speed

In the order above, I believe the procedure would be:

small black button

other small black button

small black button and large black button together

other small black button and large black button together

This is not to say that I am correct as it doesn't work but I can't think of any other combination to get the sequence.

 

[jgedde]

Re: Capacitor questions

Yello_cad Do you have 2 capicators or one? To start a single phase motor needs a start winding. The capicator provides the necessary phase shift so the motor will start in the intended direction. A switch is provided to shut off the start winding when the motor gets up to speed. If you have one capicator it's a start cap. If you have a 2 capicator motor then the smaller of the 2 is the run capicator and usually it's connected across the start speed switch. The theory being that if there is a winding used only for start and nothing while the motor is running why not get a little extra HP from it so they add the run cap. A dual capicator can be used for start and run. (simply put it's 2 capicators in one can) You say you have a dual voltage 2 speed motor, Unusual as most 2 speed motors are single voltage probably because of the number of wires it would require to make a 2 speed motor dual voltage. Not knowing what kind of motor you have makes it hard to determine why your motor will not start at High speed. Most dual speed develope the same torque on High or low speed. HP changes because HP is speed related. The faster the motor speed the more HP you will receive from the torque developed. I suspect your high speed start problem might be due a wiring error. Sorry I can't offer more help now as tomorrow I'm going on vacation!

Thanks Froneck. I've been trying to figure out for a while why some TEFC motors have a second cap. Despite research the answer eluded me.... Until now...

John

 

[yellow_cad]

Re: Capacitor questions

Frank, I do have a volt/ohm meter.

The lathe has specified high and low spindle speeds for each of the gear settings and with only the single black button (forward) pushed, my lathe spindle is traveling at the specified low speed in each gear setting. The motor speeds are 1710 and 3420.

If you try to push down the double black button alone, it will not push down but with pressure on the double black button, it will go down as soon as one of the single black buttons is also pushed. As part of the lathe, a spare switch was included. I can see the notch that the double button sits on until it is released by the single button.

In the connection drawing, the double black button wiring seems to show that low speed wires connect towards the top and high speed connect toward the bottom. My thought is that this might indicate that low speed would take place with the double button up and high speed when the double button is down.

Jim

 

[yellow_cad]

Re: Capacitor questions

I think your right about the button position, Up is Low speed and Down High speed. Does the Red Button do anything to the Large Black Button?
I don't understand the function of the notch preventing the pushing of the large button. On the spare switch when pushing one of the Small Black buttons and the Large Black button will the Large Black button remain down? If so will it reset when the Red button is pushed? You said you can start in Forward and Reverse Low speed by simply pressing one of the Small Black buttons, am I correct? Have you tried pushing the Large Black button when the motor is running in Low speed?
Can you use the Ohm meter and test the function of the Large Black button to see what contacts close when up and down? Try it on the spare switch first. Check to see that on the Small Black push buttons the associated contacts are open and close when pushed. Check the contact arrangement on the switches associated with the Large Black button. Check the motor to see if it a 2 speed 2 winding motor or 2 speed one winding motor.
The prevention of pushing in the Large Black button seems like the arrangement wants to start on Low speed. Something that would indicate 2 speed 1 winding motor. Simply put a 2 speed 2 winding motor is like two motors in one housing. 2 speed 1 winding motor has the switches changing the pole connection from 2 pole (High) to 4 pole (Low)
Frank

Yes, the large black button stays down and the small and large reset when the red is pushed.

Yes, low speed forward or reverse is gotten by pushing one or the other small black button.

On the spare switch, when one of the small black buttons is pushed (so motor would be running forward or reverse in slow speed) and then the large black button is pushed, the small black button that was pushed and is down, then immediately releases and comes up.

To check continuity, I placed the red lead (R) of the ohm meter on the terminal where the red power lead attaches and the black lead of the ohm meter on the terminal where the lathe motor black lead (Z) attaches. My circuit is open. When I push either small black button, my circuit closes. When I push a small black button, my circuit closes but when I push the large black button, the circuit opens as soon as the small black button pops up (which is immediately). But if I push the small black button and the large black button together, I get a closed circuit.

Am I checking the correct circuit?

I am not sure how to tell whether it is a 2 speed 2 winding motor or 2 speed one winding motor.

 

[yellow_cad]

Re: Capacitor questions

So what your saying is that if the motor were running in low speed and I pushed the Large Black Button the motor will stop because the the down Small Black button pops up. Then to attempt to push the Large Black button again you have to push both the Large and a Small button? Do both stay down?

There are too many current paths to check the input. I'm trying to understand the working of the switch. I do not care about the White button, Red has no contacts associated with it. I want to check the spare switch. Each Small Black button has 2 sets of contacts associated with it on each side. Red/Black test leads make no difference now. With the Small Black buttons up, put the test leads across each pair. I'm assuming they are open or no continuity between them, check both sides. Push down a Small Black button and check again. Do this with the other Small Black button. Then proceed to the Large Black button. Test all 4 contacts button UP then DOWN. I'm guessing the slow speed will have closed switches and the High speed switch open when Large Black button is up and they reverse when the Large Black button is pushed down. Is there any way to keep the Large Black button down?

Frank

In checking the small black button contacts, I am checking two pair per side per switch and each pair is side by side. All of these contacts (eight pairs for both small buttons) are open until the respective button is pushed and then they is closed. Not to confuse things but this is what happened the first time I tested and now just one of the eight pairs remains open even with the small button pushed. This may be why this is an extra switch.
In checking the large black button contacts, the low speed circuit is open until a small black button is pushed. The high speed circuit is open until one small black button and the large black button are pushed together at which time the circuit closes. If the small button is pushed and then the large button is pushed later, the small button pops up and the circuit remains open.

With one small button and the large button pushed down, there is a closed circuit as noted above but there are also lots of closed circuits between the high speed terminals and most but not all of the eight terminals (front and back) on the small buttons and this is not exclusive to the small button that is pushed. A similar occurrence takes place with the low speed circuit and I can't seem to get a hard and fast pattern.

The only way to keep the large black button down is to press it and a small black button together and this gets a closed circuit. The large black button will stay down physically if the small button is pressed first and then the large button is pushed and the small button pops up but there are no closed circuits between any terminals at all.

 

[yellow_cad]

Re: Capacitor questions

Are there any wires on the spare switch? I don't understand how the Small Black button changes the contacts on the Large Black button switch? Is there some internal connection?
What you are saying and correct me if I wrong, there is no contact between the terminals of the low speed switch on the Large Black button associated contacts until one of the Small Black buttons is pushed. and your required to push a Small Black button and the Large Black button to close the contacts on the High speed switch. To rephrase your words your saying that the Small Black button controls the switches under the Large Black button and that the large Black button directs which 2 sets of contacts High or Low are switched by the Small Black buttons? If so that's not a problem!
Can you remove the motor wires, mark them so that they can be reconnected.
Connect one test lead on R (all power removed) push one Small Black Button and check continuity to V1, V2, X1, X2 and Z plus the non motor side of the capacitor. Push Red button and then Push the other Small Black button and check the continuity same as above. Push Red button. Now push one Small Black button and the Large Black button at the same time and repeat the continuity test. Push Red button and repeat the test pushing the other Small Black Button and the Large Black button at the same time. This will test to see if your motor is getting voltage at High Speed to all needed connections.
Remove the one test lead from R and connect to S. Repeat the test above. Would help if you make a chart of the results
Frank

Yes, there are at least 15 wires connecting various terminals front and back.

Yes, both small and large black buttons needed to be pushed together in order to get a closed circuit in the previous tests.

Instead of disconnecting the power, I am using the spare switch. To test both sides of the active switch, I would need to disconnect all leads and remove it from the lathe. Here are the results with the sample switch:

Closed circuits with one lead of ohm meter on R:

End small button and large button pushed:

V2 and the terminals to either side
Z and the rest of terminals on that lower row

Inboard small button and large button pushed:

Terminal directly below R
Lathe capacitor terminal and the terminal to the immediate right of it
Terminal to the right of milling motor White/Capacitor
Middle 2 terminals on bottom row on other side


Closed circuits with one lead on S:

End small button and large button pushed:

Lathe capacitor terminal
Terminal to the right of S
3rd terminal to the left of R
V1 terminal
4 terminals making up the top row on the other side

Inboard small button and large button pushed:

3 terminals to the left of R
Terminals V1 and V2 and the 2 terminals to the right of them
Terminal to the right of X1
Terminal to the right of X2
4 terminals making up the top row on the other side


I also tested for closed circuits with the large black button only pushed and the results are:

With the ohm tester lead on R:

Terminal to the left of S
Terminal to the right of milling motor White/Capacitor
Middle 2 terminals in the lower row on the other side

With the ohm tester lead on S:

Terminal to the right of milling motor Black
3 terminals to the left of R
Middle 2 terminals in the top row on the other side

 

[yellow_cad]

Re: Capacitor questions

Frank, I really hate to interrupt this since I really appreciate your help, but this weekend my daughter is getting married out of town and I'm leaving in the morning and will be back Tuesday.

When I return, I will check the switch in the lathe. As best as I can tell, there is no motor plate. Just a group of wires come out of the motor and into the compartment that houses the switch and capacitors.

To clarify my testing procedure, according to your previous post, I thought I was to test the circuit between first R and then S with V1, V2, X1, X2, Z, and the non motor side of the capacitor. In your latest post you give the example of checking the circuit V1-Z. So now I'm just a little confused as to exactly which circuits I am to check. Also, in my testing procedure, I assume that when checking circuits, I will ignore all of the many terminals unless those terminals are directly connected to one of the leads in question (for example: V1, V2, X1, X2, R, S, etc).

On the markings in the manual, this machine is obsolete and I had no manual. I contacted the factory and they emailed me the manual you see and it already had all of the markings. None of the markings pertain to this machine. That being said, when I got the machine, the milling head didn't run until I replaced the capacitor. Another red flag is the fact that I have this extra switch. Also, when I look at the switch that is in the lathe, the jumper wires (of which I counted 15) look a little less professionally done than do the jumper wires on the extra switch.

As to "throwing caution to the wind", I really don't want to do that as now the machine runs in low range forward and reverse. I am quite aware that I could end up with nothing running at all or everything running. I don't know if I am willing to take that chance. I believe I am looking for a more cautious approach.

Thanks again for all the help.

Jim