Tablesaw motor

[CAMAN]

What would make a 120 volt motor sound like it is running too fast? My tablesaw has been running fine until today. I was using it and it sounds like it is running about double the normal speed and has a distinct over-heating smell when running. It also ran for about 10 seconds with no load and tripped my breaker once. I have ran it on this circuit numerous times, and also tried a different circuit with the same problem.

I fully disassembled the motor to inspect it and the armature was too hot to hold for quite a while after it was last run. I checked both the armature and field as much as I could with my meter and nothing stood out to be bad.

This saw also has a soft start switch, and have no idea how to check if it is working properly, but the circuit board looks good(unburnt).

Ideas?

[JeremyCampbell]

Just an idea, might be a power serge of some sort going on.Just too test this hypothesis, run a light on that circuit and see if the light glows at an abnormal extreme brightness.Happened to me once and concluded that moisture in the circut had a factor in all the mischief.

[CAMAN]

Thanks Jeremy, I checked the outlet and it was running around 120 volts so I don't believe it is a surge. I also had my miter saw connected to the same outlet at the same time and it seems to be running just fine.

[delcecchi]

It probably depends on what kind of motor it is. But my first guess would be a short somewhere in the windings. That would make it draw too much current, and maybe spin too fast if it takes out a couple poles on the motor.

[Surface Tension]

What type of start/run cap?

If it has a centrifugal switch thats stuck I could see this running up on RPMs.

[CAMAN]

There is no capacitor. It has a soft start switch

Here is a picture of it.

The red comes from the paddle switch, black goes to motor, and white is neutral.

So far I have found one other person on another forum that has experienced this issue with the same saw (Ridged R4510), they haven't replied to me yet if they figured out the issue. I called customer service and they say they have never heard of it before and sounded confused. This saw is now out of warranty so I just want to figure out if it's the motor, or switch as I really don't want to throw an $80 part in then find out it wasn't the problem and then have to throw another $200-300+ in.

Anybody have a motor guy they can recommend in the South Metro? I'd like someone who has the ability to fully test it and if it turns out good I will go ahead and pick up the soft start switch.

[LightningBG]

Did you register the saw for the Lifetime Service Agreement?

I have that same saw. I've had to replace the switch toggle but thats it in the 5-6 years I've had it.

[LightningBG]

Here is a video, seems like the guy may have experienced the same as you?

Information down in the comments.

Vid

[Surface Tension]

Missed the soft start switch part and that is more then likely your problem.

I don't know how to test it but can't find a reason(maybe there is)why you couldn't eliminate the soft switch for testing purposes only of the motor.

[CAMAN]

I would just wire in a regular switch to test it but I have no idea if the soft start is supposed to regulate the power going to the motor to a lower voltage/amperage to keep the RPM's down and it for some reason is not regulating anymore and the reason it is running at a higher speed. Thus if I just throw another switch in and it does the same thing that would make you think it is the motor, but not necessarily.

Thanks for the video Lightning, I do believe I have the LSA, but when I talked to Customer Service the other day they didn't seem too interested in even helping me.

Once I get some time I will be bringing the motor in to at least get inspected and hopefully they will be able to tell me if the armature or field is good or bad (as I can get each separately [$90 for the Field and $120 for the Armature]. If they say the motor is good I will pick up the switch[$65].

Thanks everyone, I will update when I figure out what is going on. And if anyone knows of any good electric motor guys in the south metro please let me know.