Split phase motor question

I have an old split phase induction motor that runs quite well.
Especially considering the fact that it is at least 60 years old. But
it makes a funny sound when running but the sound disappears
immediately whe power is removed. It sounds like something is a little
loose. Sorta like if the shaft was oscillating back and forth between
the thrust bearings. But it is not that. My son suggested that maybe
one of the windings is loose and rattles a little back and forth when
the polarity of the AC voltage changes. Anybody got a clue?
Thanks,
Eric

 

[Tim Wescott]

On Mon, 06 Oct 2014 17:08:27 -0700, etpm wrote:

I have an old split phase induction motor that runs quite well.
Especially considering the fact that it is at least 60 years old. But it
makes a funny sound when running but the sound disappears immediately
whe power is removed. It sounds like something is a little loose. Sorta
like if the shaft was oscillating back and forth between the thrust
bearings. But it is not that. My son suggested that maybe one of the
windings is loose and rattles a little back and forth when the polarity
of the AC voltage changes. Anybody got a clue?
Thanks,
Eric

Even if I didn't know at least one other group that you frequent, I'd
STILL suggest that you ask over on r.c.m -- this group tends to be best
for asking why your 555 doesn't work so that we can give you the 3rd
degree to find out that you're using a 10 megohm resistor in the discharge
path, or why your drive transistor always blows out after one use, so that
we can find out you're not using a snubber.

Yes, a loose winding is a believable theory, but I'm just nodding my head
at your guess, not adding anything valuable of my own.

--

Tim Wescott
Wescott Design Services
http://www.wescottdesign.com

 

[Jasen Betts]

On 2014-10-07, etpm@whidbey.com <etpm@whidbey.com> wrote:

I have an old split phase induction motor that runs quite well.
Especially considering the fact that it is at least 60 years old. But
it makes a funny sound when running but the sound disappears
immediately whe power is removed. It sounds like something is a little
loose. Sorta like if the shaft was oscillating back and forth between
the thrust bearings. But it is not that. My son suggested that maybe
one of the windings is loose and rattles a little back and forth when
the polarity of the AC voltage changes. Anybody got a clue?
Thanks,

I've seen some with a centrifugal switch inside, dunno if for speed
regulation or for start/run

--
umop apisdn

 

[George Herold]

On Tuesday, October 7, 2014 3:46:01 AM UTC-4, Jasen Betts wrote:

On 2014-10-07, etpm@whidbey.com <etpm@whidbey.com> wrote:

I have an old split phase induction motor that runs quite well.

Especially considering the fact that it is at least 60 years old. But

it makes a funny sound when running but the sound disappears

immediately whe power is removed. It sounds like something is a little

loose. Sorta like if the shaft was oscillating back and forth between

the thrust bearings. But it is not that. My son suggested that maybe

one of the windings is loose and rattles a little back and forth when

the polarity of the AC voltage changes. Anybody got a clue?

Thanks,

I've seen some with a centrifugal switch inside, dunno if for speed
regulation or for start/run

Yeah I've got an oldie that runs a little bench grinder. It's got said centrifugal switch inside.
I can hear it click in when it comes up to speed.

George H.

--

umop apisdn

 

On Tue, 7 Oct 2014 08:21:44 -0700 (PDT), George Herold
<gherold@teachspin.com> wrote:

On Tuesday, October 7, 2014 3:46:01 AM UTC-4, Jasen Betts wrote:
On 2014-10-07, etpm@whidbey.com <etpm@whidbey.com> wrote:

I have an old split phase induction motor that runs quite well.

Especially considering the fact that it is at least 60 years old. But

it makes a funny sound when running but the sound disappears

immediately whe power is removed. It sounds like something is a little

loose. Sorta like if the shaft was oscillating back and forth between

the thrust bearings. But it is not that. My son suggested that maybe

one of the windings is loose and rattles a little back and forth when

the polarity of the AC voltage changes. Anybody got a clue?

Thanks,

I've seen some with a centrifugal switch inside, dunno if for speed
regulation or for start/run

Yeah I've got an oldie that runs a little bench grinder. It's got said centrifugal switch inside.
I can hear it click in when it comes up to speed.

George H.

--

umop apisdn

This motor does indeed have a centrifugal switch inside. I thought
about out of balance but the noise stops as soon as power is removed.
If spun up with a drill motor it does not make the noise. Only when
powerd up does it exhibit this behavior.
Eric

 

[Jasen Betts]

On 2014-10-07, etpm@whidbey.com <etpm@whidbey.com> wrote:

This motor does indeed have a centrifugal switch inside. I thought
about out of balance but the noise stops as soon as power is removed.
If spun up with a drill motor it does not make the noise. Only when
powerd up does it exhibit this behavior.
Eric

when you turn the power off the motor doesn't get faster so the switch
won't cycle. can you do a speed measurement, does it click while
speedinng up, or only at full speed?

--
umop apisdn

 

[ScottWW]

wrote in message news:ccb63a9ditpveahof8958bhk872v55ng7e@4ax.com...

I have an old split phase induction motor that runs quite well.
Especially considering the fact that it is at least 60 years old. But
it makes a funny sound when running but the sound disappears
immediately whe power is removed. It sounds like something is a little
loose. Sorta like if the shaft was oscillating back and forth between
the thrust bearings. But it is not that. My son suggested that maybe
one of the windings is loose and rattles a little back and forth when
the polarity of the AC voltage changes. Anybody got a clue?
Thanks,
Eric

Long-term overheating can make brittle the plastic insulating lining between
copper and steel, allowing the windings to move slightly. If it is winding
movement, it would sound like 60Hz buzz. If its possible to lock the rotor,
this noise would occur without rotor movement.
A loose winding like this can short to the core and be a possible shock
hazard.
Scott

 

[George Herold]

On Wednesday, October 8, 2014 2:06:36 PM UTC-4, et...@whidbey.com wrote:

On 8 Oct 2014 09:10:59 GMT, Jasen Betts <jasen@xnet.co.nz> wrote:



On 2014-10-07, etpm@whidbey.com <etpm@whidbey.com> wrote:



This motor does indeed have a centrifugal switch inside. I thought

about out of balance but the noise stops as soon as power is removed.

If spun up with a drill motor it does not make the noise. Only when

powerd up does it exhibit this behavior.

Eric



when you turn the power off the motor doesn't get faster so the switch

won't cycle. can you do a speed measurement, does it click while

speedinng up, or only at full speed?

It is not the centrifugal switch, it operates normally. It clicks once

wehn the motor is nearly up to speed and then again when the motor has

slowed down to about 50% speed. The sound it makes is a knocking

sound, like someone was pulling and pushing on the shaft so that it

hits the thrust bearings at either end. But the shaft isn't moving

back and forth. Maybe I can look at the sound with a 'scope and

determine the frequency.

Eric

The old motor I have does rattle back and forth some times... but it is the shaft moving. I switch power on and off and that will usually stop it.
It won't get up to speed in the rattle mode. Hey maybe we have the same motor? (I'll try and remember to go get a part number off it.)

 

On 8 Oct 2014 09:10:59 GMT, Jasen Betts <jasen@xnet.co.nz> wrote:

On 2014-10-07, etpm@whidbey.com <etpm@whidbey.com> wrote:

This motor does indeed have a centrifugal switch inside. I thought
about out of balance but the noise stops as soon as power is removed.
If spun up with a drill motor it does not make the noise. Only when
powerd up does it exhibit this behavior.
Eric

when you turn the power off the motor doesn't get faster so the switch
won't cycle. can you do a speed measurement, does it click while
speedinng up, or only at full speed?

It is not the centrifugal switch, it operates normally. It clicks once
wehn the motor is nearly up to speed and then again when the motor has
slowed down to about 50% speed. The sound it makes is a knocking
sound, like someone was pulling and pushing on the shaft so that it
hits the thrust bearings at either end. But the shaft isn't moving
back and forth. Maybe I can look at the sound with a 'scope and
determine the frequency.
Eric

 

On Wed, 8 Oct 2014 09:08:34 -0400, "ScottWW" <spamtrap@dcorp.com>
wrote:

wrote in message news:ccb63a9ditpveahof8958bhk872v55ng7e@4ax.com...

I have an old split phase induction motor that runs quite well.
Especially considering the fact that it is at least 60 years old. But
it makes a funny sound when running but the sound disappears
immediately whe power is removed. It sounds like something is a little
loose. Sorta like if the shaft was oscillating back and forth between
the thrust bearings. But it is not that. My son suggested that maybe
one of the windings is loose and rattles a little back and forth when
the polarity of the AC voltage changes. Anybody got a clue?
Thanks,
Eric

Long-term overheating can make brittle the plastic insulating lining between
copper and steel, allowing the windings to move slightly. If it is winding
movement, it would sound like 60Hz buzz. If its possible to lock the rotor,
this noise would occur without rotor movement.
A loose winding like this can short to the core and be a possible shock
hazard.
Scott

Greetings Scott,
This motor is about 80 years old. There is no plastic inside. It does
have two bakelite knobs on the outside that screw onto the wire
terminals.
Eric

 

[DaveC]

I have an old split phase induction motor that runs quite well.
Especially considering the fact that it is at least 60 years old. But
it makes a funny sound when running but the sound disappears
immediately whe power is removed. It sounds like something is a little
loose. ...
Eric

These motors are pretty simple in construction. Why not take it apart and see
if you can locate a loose centrifugal switch part or such?

d.

 

On Wed, 8 Oct 2014 12:41:22 -0700, DaveC <invalid@invalid.net> wrote:

I have an old split phase induction motor that runs quite well.
Especially considering the fact that it is at least 60 years old. But
it makes a funny sound when running but the sound disappears
immediately whe power is removed. It sounds like something is a little
loose. ...
Eric

These motors are pretty simple in construction. Why not take it apart and see
if you can locate a loose centrifugal switch part or such?

d.

I have had it apart to clean and oil it. It is not the centrifugal
switch. It is not the rotor causing the shaft to bang back and forth
against the thrust bearings. I am, frankly, mystified. That's why I
posted here for help. I think I really need to hook up a mike to my
'scope and check the frequency. If it is 60 cycles then it most likely
is caused, I think, by changing magnetic fields. It may also be caused
by the pulsating nature of the single phase power making the motor
speed also pulsate at 60 cycles, but I don't think so.
Eric

 

[Michael A. Terrell]

etpm@whidbey.com wrote:

Greetings Scott,
This motor is about 80 years old. There is no plastic inside. It does
have two bakelite knobs on the outside that screw onto the wire
terminals.

It would use 'Fish Paper' to insulate the windings from the
laminations.

--
Anyone wanting to run for any political office in the US should have to
have a DD214, and a honorable discharge.

 

[Michael A. Terrell]

Jasen Betts wrote:

On 2014-10-07, etpm@whidbey.com <etpm@whidbey.com> wrote:

This motor does indeed have a centrifugal switch inside. I thought
about out of balance but the noise stops as soon as power is removed.
If spun up with a drill motor it does not make the noise. Only when
powerd up does it exhibit this behavior.
Eric

when you turn the power off the motor doesn't get faster so the switch
won't cycle. can you do a speed measurement, does it click while
speedinng up, or only at full speed?

The switch kicks out when the motor starts running, well before
reaching full speed. Another method uses a potential relay and a
starting capacitor.

I just had to rebuild a dual capacitor pump control for my well. Then
the 22 year old pump quit pumping water even though the motor is
running. A clamp on ammeter shows the right current on each of the
three leads. Now, I get to pull the pump of of the 80' casing to put in
a new pump. Of course, I've found no one to help lift it.

The above ground pump on my dad's well failed. The well driller
refused to repair it, and charged him $3800 to drill a new well because
it was over 10 years old.


--
Anyone wanting to run for any political office in the US should have to
have a DD214, and a honorable discharge.

 

[George Herold]

On Wednesday, October 8, 2014 2:29:07 PM UTC-4, George Herold wrote:

On Wednesday, October 8, 2014 2:06:36 PM UTC-4, et...@whidbey.com wrote:


The old motor I have does rattle back and forth some times... but it is the shaft moving. I switch power on and off and that will usually stop it.

It won't get up to speed in the rattle mode. Hey maybe we have the same motor? (I'll try and remember to go get a part number off it.)

This is what I have. (Well almost I have style 2452171)
http://www.ebay.com/itm/Vintage-Westinghouse-1-4-HP-AC-Electric-Motor-1-phase-110-V-1725-Rpm-Wood-Lathe-/271628068473?pt=LH_DefaultDomain_0&hash=item3f3e4b6679

There is a certain beauty that new motors lack.

George H.

 

[default]

On Wed, 08 Oct 2014 17:53:40 -0700, etpm@whidbey.com wrote:

On Wed, 8 Oct 2014 12:41:22 -0700, DaveC <invalid@invalid.net> wrote:

I have an old split phase induction motor that runs quite well.
Especially considering the fact that it is at least 60 years old. But
it makes a funny sound when running but the sound disappears
immediately whe power is removed. It sounds like something is a little
loose. ...
Eric

These motors are pretty simple in construction. Why not take it apart and see
if you can locate a loose centrifugal switch part or such?

d.
I have had it apart to clean and oil it. It is not the centrifugal
switch. It is not the rotor causing the shaft to bang back and forth
against the thrust bearings. I am, frankly, mystified. That's why I
posted here for help. I think I really need to hook up a mike to my
'scope and check the frequency. If it is 60 cycles then it most likely
is caused, I think, by changing magnetic fields. It may also be caused
by the pulsating nature of the single phase power making the motor
speed also pulsate at 60 cycles, but I don't think so.
Eric

Sounds like you are saying you know what is wrong. The shaft moving
back and forth along it's axis?

Then you either need to limit the travel of the shaft, or fix whatever
is wrong with the load causing the shaft to move.

Thrust bearings? Often as not a thin metal washer, the bearings are
there mostly to deal with radial loading.

Is the rotor balanced?

 

[default]

On Wed, 08 Oct 2014 23:42:35 -0400, "Michael A. Terrell"
<mike.terrell@earthlink.net> wrote:

Jasen Betts wrote:

On 2014-10-07, etpm@whidbey.com <etpm@whidbey.com> wrote:

This motor does indeed have a centrifugal switch inside. I thought
about out of balance but the noise stops as soon as power is removed.
If spun up with a drill motor it does not make the noise. Only when
powerd up does it exhibit this behavior.
Eric

when you turn the power off the motor doesn't get faster so the switch
won't cycle. can you do a speed measurement, does it click while
speedinng up, or only at full speed?


The switch kicks out when the motor starts running, well before
reaching full speed. Another method uses a potential relay and a
starting capacitor.

I just had to rebuild a dual capacitor pump control for my well. Then
the 22 year old pump quit pumping water even though the motor is
running. A clamp on ammeter shows the right current on each of the
three leads. Now, I get to pull the pump of of the 80' casing to put in
a new pump. Of course, I've found no one to help lift it.

Sink a couple of posts and put a beam across, then use a come-along
(ratchet lever cable hoist) or block and tackle.

I lifted a big fiberglass boat and motor off a trailer using four
posts, just so I could repair the trailer. (I cheated and lifted the
boat and motor with hydraulic jacks then tied the boat and motor off
with 1/2" ropes and lowered the trailer and pushed it out)

The above ground pump on my dad's well failed. The well driller
refused to repair it, and charged him $3800 to drill a new well because
it was over 10 years old.

Considering the problem was the pump and not the well why did your OM
go for it? Sand being sucked up into the pump? 10 years old is
nothing, my above ground pump (driving a deep well inductor type
thingee) has been in service for 30 years that I know of.

 

[Michael A. Terrell]

default wrote:

On Wed, 08 Oct 2014 23:42:35 -0400, "Michael A. Terrell"
mike.terrell@earthlink.net> wrote:


Jasen Betts wrote:

On 2014-10-07, etpm@whidbey.com <etpm@whidbey.com> wrote:

This motor does indeed have a centrifugal switch inside. I thought
about out of balance but the noise stops as soon as power is removed.
If spun up with a drill motor it does not make the noise. Only when
powerd up does it exhibit this behavior.
Eric

when you turn the power off the motor doesn't get faster so the switch
won't cycle. can you do a speed measurement, does it click while
speedinng up, or only at full speed?


The switch kicks out when the motor starts running, well before
reaching full speed. Another method uses a potential relay and a
starting capacitor.

I just had to rebuild a dual capacitor pump control for my well. Then
the 22 year old pump quit pumping water even though the motor is
running. A clamp on ammeter shows the right current on each of the
three leads. Now, I get to pull the pump of of the 80' casing to put in
a new pump. Of course, I've found no one to help lift it.

Sink a couple of posts and put a beam across, then use a come-along
(ratchet lever cable hoist) or block and tackle.

I was planning on a tripod made from three 16' 2x4s, and my chain
hoist. Much safer than a come along, when you only have one good hand.


The problem right now is it's too hot to work during the day, and you
have to be careful about disease carrying mosquitoes in the mornings and
evenings. I'll have to keep hauling water for now.

I lifted a big fiberglass boat and motor off a trailer using four
posts, just so I could repair the trailer. (I cheated and lifted the
boat and motor with hydraulic jacks then tied the boat and motor off
with 1/2" ropes and lowered the trailer and pushed it out)

The above ground pump on my dad's well failed. The well driller
refused to repair it, and charged him $3800 to drill a new well because
it was over 10 years old.

Considering the problem was the pump and not the well why did your OM
go for it? Sand being sucked up into the pump? 10 years old is
nothing, my above ground pump (driving a deep well inductor type
thingee) has been in service for 30 years that I know of.

They simply refused to work on it, and he won't admit it but he can
barely walk due to a bad hip. I offered to repair it, but he's become a
pushover in his senior years. They convinced him that the piping and
hardware inside the casing was bad, instead of the old pump.


--
Anyone wanting to run for any political office in the US should have to
have a DD214, and a honorable discharge.