I called a motor repair shop this morning and was quoted $75 evaluation fee to test the motor. If they are able to fix the motor, they will apply the $75 towards the repair parts and maintenance. Not too bad, but it's a good 40 minute drive to get there.
When I explained to the service technician on the phone that I was getting 1.3 ohms between L1 (Hi Speed) and L2 (COM), he stated that should not be the case and likely that there is a problem with the 'windings', which could not be economically repaired.
So, I am shopping for a motor.
INYOpools has one in stock (cost + tax with FOC shipping) for $596.46. Your Quote 80212 - INYOPools.com
There is an alternative, but I don't really understand what is different. It cost ~ $100 less. A.O. Smith Century 2.0 HP Square Flange 56Y Dual Speed Full Rate Motor - B2984 - INYOPools.com
Is there a significant difference (other than cost) to the above two options?
Below are the readings you requested. These all seem expected to me.
Voltage at Relays Filter set to HI
T2 <-- 247 VAC --> T4
T2 <-- 123 VAC --> Ground
T4 <-- 123 VAC --> Ground
Aux 2 Relay
T2 <-- 23 VAC --> T4
T2 <-- 123 VAC --> Ground
T4 <-- 0.3 VAC --> Ground
The black jumper connecting the #2 terminal on both relays will make the number 2 terminal hot whenever either relay is activated.
So, the 120 from either #2 terminal to ground is expected whenever either relay is activated.
I did not expect that the reading from 2 to 4 on the inactive relay would be above zero, but it could be because the #2 terminal is hot.
With the jumper removed, the inactive relay should read zero volts from 2 to 4 and from 2 to ground and from 4 to ground.
I’m thinking that the motor likely has the low speed windings shorted to ground, which could cause the low speed windings to be powered because the current has a path from L2 (common) through part of the windings to ground.
If the resistance from any of the motor terminals to ground shows anything other than O.L, then I think that shorted windings are the most likely cause.
Since the motor is relatively new, it would be unusual for the windings to fail.
However, the debris that was stuck in the start switch contacts probably held the start windings out of the circuit.
With no start windings or start capacitor, the low speed windings would overheat while trying to start.
The motor should have a thermal overload, which should protect the windings from burning up.
Maybe the thermal overload didn’t work correctly or maybe the windings just eventually failed from trying to start too much.
Even if the low speed windings were open, the high speed windings should still work unless the low speed windings are grounding out.
The low speed windings are connected on one end to the common terminal.
So, if the low speed windings were grounded to the motor frame, then current would go from the common terminal to ground when on high speed. This would power the low speed windings with 120 volts coming from the common terminal with the ground acting as a neutral. This would interfere with the high speed windings and cause the motor to overheat.
If the windings are grounded, then you should get a resistance value when testing from a motor terminal to the motor ground screw.
If the resistance from all motor terminals to the motor ground screw is O.L, then maybe something else is going on.
Also, it’s hard to tell, but the centrifugal switch weights look like they are not sitting exactly right.
If you get the correct values for the readings on relay voltage while the #2 jumper is off, then I suspect that a new motor will probably work.
In the final analysis, the entire problem might have been caused by a one in a million chance piece of debris getting into the open contacts while the motor was running.
Hi James, Sorry for my lack of response. I was running out of time in anticipation for the hard freeze forecast for my area this past week, so I went ahead and purchased a new motor. I received the new motor the day before the freeze and was able to get it installed and working. I am keeping the old motor with the plan to do more testing on the bench. If I can get it fixed, then I will have a good spare. Thank you for all the help... Stay warm...