1PH motor fail to start, locked rotor amps, possibly rotor touching stator
1PH motor fail to start, locked rotor amps, possibly rotor touching stator
(OP)
Got stuck putting bearings in a table saw for someone. The motor is the oddest thing I have ever seen. The Al case splits all the way down axially and the stator is removed from the cases. Technically, I do not believe it is supposed to be serviced. The stator and bearings were bedded in epoxy.
Any, I was with the saw when it failed. It was running doing light plastic cuts solid for 1hr. It just got a vibration very quickly and created some wood smoke from being hot. The bearings really were not that bad and certainly did not cause the vibration.
I found a bad run cap. changed that and the bearings. Motor will not start. Growls, shaft turns a bit, pulls about 5-6x FLA. We obviously don't leave it in this state for even a full second.
I don't know that I have ever had a motor's rotor contact the stator but in this design, I believe we are experiencing some of that BUT I am really unsure if that would really cause this problem? This should not cause a loss of magnetic flux should it? If contact with the stator would not cause a locked rotor state, any other ideas? I have an ESR meter as well and I show the start cap is still good, potential relay is normally close right now, bleed resistor is working, etc.
I don't have a specific diagram for this motor but it seems odd. It has a non contact inductive coil on the tail I assume to operate the potential relay. Never seen that. Usually a switch or relay operates off of start winding.
Any, I was with the saw when it failed. It was running doing light plastic cuts solid for 1hr. It just got a vibration very quickly and created some wood smoke from being hot. The bearings really were not that bad and certainly did not cause the vibration.
I found a bad run cap. changed that and the bearings. Motor will not start. Growls, shaft turns a bit, pulls about 5-6x FLA. We obviously don't leave it in this state for even a full second.
I don't know that I have ever had a motor's rotor contact the stator but in this design, I believe we are experiencing some of that BUT I am really unsure if that would really cause this problem? This should not cause a loss of magnetic flux should it? If contact with the stator would not cause a locked rotor state, any other ideas? I have an ESR meter as well and I show the start cap is still good, potential relay is normally close right now, bleed resistor is working, etc.
I don't have a specific diagram for this motor but it seems odd. It has a non contact inductive coil on the tail I assume to operate the potential relay. Never seen that. Usually a switch or relay operates off of start winding.





RE: 1PH motor fail to start, locked rotor amps, possibly rotor touching stator
"Will work for (the memory of) salami"
RE: 1PH motor fail to start, locked rotor amps, possibly rotor touching stator
RE: 1PH motor fail to start, locked rotor amps, possibly rotor touching stator
"Will work for (the memory of) salami"
RE: 1PH motor fail to start, locked rotor amps, possibly rotor touching stator
RE: 1PH motor fail to start, locked rotor amps, possibly rotor touching stator
RE: 1PH motor fail to start, locked rotor amps, possibly rotor touching stator
I was looking at diagrams for standard dual voltage single phase motors but they have 6 wires, this one has 5. I cannot seem to figure out which point they have tied to make the 5 wires. I figured T4/T5 but the whole thing just tests strange. Just when I think I have my main winding wires, something else conducts. Neither side of the start cap connect directly to power, they go to motor leads.
RE: 1PH motor fail to start, locked rotor amps, possibly rotor touching stator
Is there anything we can inspect on the rotor aside from growler testing?
RE: 1PH motor fail to start, locked rotor amps, possibly rotor touching stator