Testing a motor, I'm confused

[mark32]

So I walk into my customers house to do some more work on his kitchen renovation when he asked me about his washing machine. He had removed the motor and said he had no continuity through the windings, "So that means it's bad right?" he asked. "Yeah, that's shot", I replied. An hour later UPS drops off a new motor, which he had orders days earlier. He hooked his tester up to the terminals and still no continuity? You can't see it in the pic, but there is a conductor that joins the windings together on the opposite side of view. There is continuity however around that thermal overload. He asked if he should check the ohms through the windings. "Nah, if that multimeter won't show continuity it won't read any ohms" I stated. Seconds later he reads 33 ohms (On the meter's lowest ohm setting) on both motors. What the...??

So I need to know why we couldn't read "Continuity" through those motors but yet it showed ohms.

 

[big john]

If continuity is considered an indicator of "good" conductor then there's obviously a point the meter manufacturer has to pick where a conductor is no longer "good" and continuity no longer works. So every meter I've ever used has an arbitrary upper limit on their continuity scale; it seems like it's often in the neighborhood of 50 ohms, after which the meter will read "OL."

But maybe your meter has a lower continuity threshold than most. What type is it?

 

[Aleman]

If continuity is considered an indicator of "good" conductor then there's obviously a point the meter manufacturer has to pick where a conductor is no longer "good" and continuity no longer works. So every meter I've ever used has an arbitrary upper limit on their continuity scale; it seems like it's often in the neighborhood of 50 ohms, after which the meter will read "OL."

But maybe your meter has a lower continuity threshold than most. What type is it?

That's right. Continuity checks are just that, checking for very low resistance from point to point. Motor windings are not a dead short to DC test voltage so the OHMs function is used.

 

[PetrosA]

It's got to be connected to whatever threshold is set in the DMM. I have a DMM that allows me to set the threshold myself for continuity which is handy. It came from the factory set at like 15-18 ohms and wouldn't beep continuity on a 90W halogen flood. After almost throwing out a few lamps and reading the instructions to the meter, I figured it out.

 

[Besoeker]

Where is the rotor?

 

[mark32]

Thanks guys, I thought I was losing my mind. The meter the home owner had was just a no name $10 multi-meter. The thought crossed my mind about the meter's continuity thresh hold but didn't think it would be set that low. Thanks again, my sanity is still in check

Besoeker, the rotor was laying somewhere, I didn't really look at it, but it was housed in plastic.