A new motor makes a humming sound without running.

[skbr2019]

A new motor makes a humming sound without running. Please help me!

Here is my motor's story.

1) The pump motor made a humming sound and not running. After a few seconds, the breaker tripped.

2) Replaced a new capacitor; tried two new capacitors; shaft can move manually, no blockage in the impeller.

3) The pump motor made a humming sound again. Immediately the breaker tripped.

4) Disconnected the motor from the breaker.

5) The breaker does not trip without connecting the motor and so I thought the problem is from the motor.

6) Installed a new motor (same model, see attached).

7) The pump motor made a humming sound and the motor did not run but the breaker does not trip. The shaft can move manually, no blockage in the impeller.

8) Replaced a new capacitor but till a humming sound and the breaker does not trip

9) Replaced the switch (V-shape) connected to the capacitor: the motor is not still running.

What else I can do? I am suspicious the new motor might be bad and so might buy a new motor again.

Attached the name plate of motor.

 

[1poolman1]

A new motor makes a humming sound without running. Please help me!

Here is my motor's story.

1) The pump motor made a humming sound and not running. After a few seconds, the breaker tripped.

2) Replaced a new capacitor; tried two new capacitors; shaft can move manually, no blockage in the impeller.

3) The pump motor made a humming sound again. Immediately the breaker tripped.

4) Disconnected the motor from the breaker.

5) The breaker does not trip without connecting the motor and so I thought the problem is from the motor.

6) Installed a new motor (same model, see attached).

7) The pump motor made a humming sound and the motor did not run but the breaker does not trip. The shaft can move manually, no blockage in the impeller.

8) Replaced a new capacitor but till a humming sound and the breaker does not trip

9) Replaced the switch (V-shape) connected to the capacitor: the motor is not still running.

What else I can do? I am suspicious the new motor might be bad and so might buy a new motor again.

Attached the name plate of motor.

What voltage is being supplied. If 120V the voltage selector at the back of the motor must be moved to that position. If it is supposed to be 240V, be sure that voltage is getting to the motor when the switch or timeclock is "on." Test between the two terminals that the wires attach, not each one to ground. Test the voltage at the breaker. If it is a 2-pole 240V breaker, test between the two screws at each pole with the breaker on. BE CAREFUL with live panels and wiring.

 

[JamesW]

The motor looks used and it is about 3 years old.

Can you show the wiring in the back?

 

[skbr2019]

What voltage is being supplied. If 120V the voltage selector at the back of the motor must be moved to that position. If it is supposed to be 240V, be sure that voltage is getting to the motor when the switch or timeclock is "on." Test between the two terminals that the wires attach, not each one to ground. Test the voltage at the breaker. If it is a 2-pole 240V breaker, test between the two screws at each pole with the breaker on. BE CAREFUL with live panels and wiring.

Thank you so much for your reply.

I have a one-pole 115V breaker and so used my old 115V motor for a few years.

According to the manual of the new motor (Century UST1102), the new motor has a factory setting at 230V and so I changed the voltage selector to 115V but the breaker tripped when I turned on the motor.

Later, I found out the factory setting was not 230V in this TFP (Voltage labeling is not correct) and so changed it to 115V again. When I turned on the motor, it still hums and the breaker does not trip. I am not sure if this is still an electric problem.

 

[skbr2019]

The motor looks used and it is about 3 years old.

Can you show the wiring in the back?

Yes, you are right. The picture is the old motor but I got a same model. I know the same model has slightly different arrangement of components in the back. I will post a pic for a new motor later because I took pictures for only old one.

Basically, the white wire (neutral) is to L2, the black wire (hot) is to L1, and the ground wire is to green. I found out the factor label of voltage selector was wrong and placed it to correct 115V.

 

[JamesW]

I found out the factor label of voltage selector was wrong and placed it to correct 115V.

They come wired for 230 and the labels are confusing.

 

[JamesW]

They print the arrow in the wrong place.

I put a red line where the arrow should be.

The arrow should line up with the bottom of the two wires in the jumper.

For 230 volts, the bottom wire of the jumper lines up with the 230 arrow and the top wire in the jumper does not connect to anything.

For 115 volts, the bottom wire of the jumper lines up with the 115 volt arrow and the top wire in the jumper lines up with the 230 arrow.

 

[JamesW]

This is wired for 230 volts.

 

[JamesW]

Most likely, you have the jumper in the wrong position.

 

[skbr2019]

Most likely, you have the jumper in the wrong position.

They print the arrow in the wrong place.

I put a red line where the arrow should be.

The arrow should line up with the bottom of the two wires in the jumper.

For 230 volts, the bottom wire of the jumper lines up with the 230 arrow and the top wire in the jumper does not connect to anything.

For 115 volts, the bottom wire of the jumper lines up with the 115 volt arrow and the top wire in the jumper lines up with the 230 arrow.

View attachment 496196

They print the arrow in the wrong place.

I put a red line where the arrow should be.

The arrow should line up with the bottom of the two wires in the jumper.

For 230 volts, the bottom wire of the jumper lines up with the 230 arrow and the top wire in the jumper does not connect to anything.

For 115 volts, the bottom wire of the jumper lines up with the 115 volt arrow and the top wire in the jumper lines up with the 230 arrow.

View attachment 496196

Most likely, you have the jumper in the wrong position.

Thank you so much for your reply.
My motor looks very similar to yours.

As you can see the attached, I moved the jumper to the position for 115V.
The motor ran for a few seconds and then the breaker tripped; I saw the shaft moving in the back.
I think I placed previously the jumper at the position for 230V. In this case, the motor keeps making a humming sound, but the breaker does not trip.

 

[skbr2019]

Thank you so much for your reply.
My motor looks very similar to yours.

As you can see the attached, I moved the jumper to the position for 115V.
The motor ran for a few seconds and then the breaker tripped; I saw the shaft moving in the back.
I think I placed previously the jumper at the position for 230V. In this case, the motor keeps making a humming sound, but the breaker does not trip.

I tried a new capacitor and a new switch (V-shape) when the jumper is in the position for 230V. Do you think if it would worth trying a new capacitor in the position for 115V?

 

[JamesW]

It looks like the copper V switch is bent up, which is probably due to the centrifugal weights part underneath being stuck in the wrong position.

This will prevent the switch from opening and it will damage the capacitor.

 

[skbr2019]

It looks like the copper V switch is bent up, which is probably due to the centrifugal weights part underneath being stuck in the wrong position.

This will prevent the switch from opening and it will damage the capacitor.

Thank you for your opinion. I will replace a capacitor and switch and let you know how it works.

 

[JamesW]

The button of the copper V switch sits on the part with the red dot.

That part is up when the pump is off and it goes down when the pump is at full speed.

It looks like the part has been pushed into the wrong position causing it to be stuck.

The weights are held back by the springs when the motor is off.

The weights swing out as the motor begins to turn due to centrifugal force.

Make sure that the part can move up and down by lifting the weights.

 

[JamesW]

Make sure that the wires are put between the posts because if they are in front of the posts, they can be caught by the weights as they swing out and wires will be ripped out of the connections or broken.

 

[JamesW]

 

[skbr2019]

1) Confirmed 120 Voltage at the wires from the breaker, the timer, the switch controlling the pump, a hot wire/ neutral wire, and L1/L2 on the motor
2) Checked a new capacitor and the old one from a new motor with a multimeter; the old one is bad.
3) Replaced a new capacitor and a V-shape switch. Made sure if all wires are placed properly.
4) The motor ran for a few seconds and the breaker tripped………
5) Detached the motor from the house
6) Checked if the impeller can run; it ran for a few seconds and the breaker tripped.
Do you have any suggestions?

 

[JamesW]

Maybe the Governor is stuck.

Does the copper V switch actually open?

 

[skbr2019]

Hi James,

I installed the second brand-new motor again after checking a capacitor.
The V-shape switch can let the motor start and the motor can run a little longer (30 seconds, haha) but the breaker tripped again. When I hold the motor shaft with a wrench to attach the impeller to the motor, can I damage the governor?
How can I check if the governor is working well or not?

 

[JamesW]

Can you post a video of the wiring compartment as the pump tries to start?