Is this a very poor description or am I ignorant?...

[amdx]

*What exactly is the Work of Start Capacitor?*

For single-phase motors normally have both the run and start capacitor.
However, they work differently. The start capacitor produces a bolt of
energy to the motor for it to run; while for run capacitor helps
maintain the functioning of the motor when the start capacitor switches
off. Start capacitor has the ability to store more charge than the run
capacitor.

Something else to observe with a start capacitor is getting burn out
since they work is to accumulate energy to speedily burst it out to
start the motor. How can you tell if the start capacitor is bad? You can
identify through two signs. First, when your motor is not starting after
you ignite it as usual, or if it takes longer than expected to respond.
It means the start capacitor is dead or almost to go bad completely.

> https://understanding-air-compressors.com/compressor-capacitors/

 My explanation would be, the run capacitor causes a phase shift of the
current in the start winding, this in relationship to the main winding
cause an increase in torque to start the motor.

I think they are using more of a DC analogy, that I don\'t think applies.

Mikek


--
This email has been checked for viruses by Avast antivirus software.
https://www.avast.com/antivirus

 

[Ricketty C]

On Friday, July 17, 2020 at 12:27:17 PM UTC-4, amdx wrote:

*What exactly is the Work of Start Capacitor?*

For single-phase motors normally have both the run and start capacitor.
However, they work differently. The start capacitor produces a bolt of
energy to the motor for it to run; while for run capacitor helps
maintain the functioning of the motor when the start capacitor switches
off. Start capacitor has the ability to store more charge than the run
capacitor.

Something else to observe with a start capacitor is getting burn out
since they work is to accumulate energy to speedily burst it out to
start the motor. How can you tell if the start capacitor is bad? You can
identify through two signs. First, when your motor is not starting after
you ignite it as usual, or if it takes longer than expected to respond.
It means the start capacitor is dead or almost to go bad completely.

https://understanding-air-compressors.com/compressor-capacitors/

 My explanation would be, the run capacitor causes a phase shift of the
current in the start winding, this in relationship to the main winding
cause an increase in torque to start the motor.

I think they are using more of a DC analogy, that I don\'t think applies.

I agree that the person who wrote this web page doesn\'t really understand the function of a start capacitor. Talking about \"accumulate energy to speedily burst it out to start the motor\" as you say might make sense in a DC circuit, but not in an AC circuit.

But for most people reading the page to fix their AC this is as much as they need. Bad start capacitor causes symptoms when starting the motor... good enough to replace a $5 part and move on.

--

Rick C.

- Get 1,000 miles of free Supercharging
- Tesla referral code - https://ts.la/richard11209

 

[amdx]

On 7/17/2020 11:48 AM, Ricketty C wrote:

On Friday, July 17, 2020 at 12:27:17 PM UTC-4, amdx wrote:
*What exactly is the Work of Start Capacitor?*

For single-phase motors normally have both the run and start capacitor.
However, they work differently. The start capacitor produces a bolt of
energy to the motor for it to run; while for run capacitor helps
maintain the functioning of the motor when the start capacitor switches
off. Start capacitor has the ability to store more charge than the run
capacitor.

Something else to observe with a start capacitor is getting burn out
since they work is to accumulate energy to speedily burst it out to
start the motor. How can you tell if the start capacitor is bad? You can
identify through two signs. First, when your motor is not starting after
you ignite it as usual, or if it takes longer than expected to respond.
It means the start capacitor is dead or almost to go bad completely.

https://understanding-air-compressors.com/compressor-capacitors/
 My explanation would be, the run capacitor causes a phase shift of the
current in the start winding, this in relationship to the main winding
cause an increase in torque to start the motor.

I think they are using more of a DC analogy, that I don\'t think applies.
I agree that the person who wrote this web page doesn\'t really understand the function of a start capacitor. Talking about \"accumulate energy to speedily burst it out to start the motor\" as you say might make sense in a DC circuit, but not in an AC circuit.

But for most people reading the page to fix their AC this is as much as they need. Bad start capacitor causes symptoms when starting the motor... good enough to replace a $5 part and move on.

This is from a different site,

Others have similar descriptions, It seem that\'s a common description in
the industry.

\'To do this HVAC units
<https://en.wikipedia.org/wiki/HVAC_control_system> use what are called
Start and RUN capacitors.

# *A Start Capacitor* holds an extra charge to start a motor moving.
# *A Run Capacitor* keeps a motor running smoothly with no up and down
spikes.\'


--
This email has been checked for viruses by Avast antivirus software.
https://www.avast.com/antivirus

 

[server]

On Fri, 17 Jul 2020 11:27:08 -0500, amdx <amdx@knology.net> wrote:

*What exactly is the Work of Start Capacitor?*

For single-phase motors normally have both the run and start capacitor.
However, they work differently. The start capacitor produces a bolt of
energy to the motor for it to run; while for run capacitor helps
maintain the functioning of the motor when the start capacitor switches
off. Start capacitor has the ability to store more charge than the run
capacitor.

Something else to observe with a start capacitor is getting burn out
since they work is to accumulate energy to speedily burst it out to
start the motor. How can you tell if the start capacitor is bad? You can
identify through two signs. First, when your motor is not starting after
you ignite it as usual, or if it takes longer than expected to respond.
It means the start capacitor is dead or almost to go bad completely.

https://understanding-air-compressors.com/compressor-capacitors/

 My explanation would be, the run capacitor causes a phase shift of the
current in the start winding, this in relationship to the main winding
cause an increase in torque to start the motor.

I think they are using more of a DC analogy, that I don\'t think applies.

Mikek

An single-phase induction motor can run without a run cap, but only
near synchronous speed. It needs a start cap or a shading ring to spin
up from start. Once it\'s going, the start cap can be disconnected.
Start caps are sometimes cheap electrolytics that die eventually.



--

John Larkin Highland Technology, Inc

Science teaches us to doubt.

Claude Bernard

 

[Ricketty C]

On Friday, July 17, 2020 at 1:14:34 PM UTC-4, amdx wrote:

On 7/17/2020 11:48 AM, Ricketty C wrote:
On Friday, July 17, 2020 at 12:27:17 PM UTC-4, amdx wrote:
*What exactly is the Work of Start Capacitor?*

For single-phase motors normally have both the run and start capacitor..
However, they work differently. The start capacitor produces a bolt of
energy to the motor for it to run; while for run capacitor helps
maintain the functioning of the motor when the start capacitor switches
off. Start capacitor has the ability to store more charge than the run
capacitor.

Something else to observe with a start capacitor is getting burn out
since they work is to accumulate energy to speedily burst it out to
start the motor. How can you tell if the start capacitor is bad? You can
identify through two signs. First, when your motor is not starting after
you ignite it as usual, or if it takes longer than expected to respond..
It means the start capacitor is dead or almost to go bad completely.

https://understanding-air-compressors.com/compressor-capacitors/
 My explanation would be, the run capacitor causes a phase shift of the
current in the start winding, this in relationship to the main winding
cause an increase in torque to start the motor.

I think they are using more of a DC analogy, that I don\'t think applies.
I agree that the person who wrote this web page doesn\'t really understand the function of a start capacitor. Talking about \"accumulate energy to speedily burst it out to start the motor\" as you say might make sense in a DC circuit, but not in an AC circuit.

But for most people reading the page to fix their AC this is as much as they need. Bad start capacitor causes symptoms when starting the motor... good enough to replace a $5 part and move on.

This is from a different site,

Others have similar descriptions, It seem that\'s a common description in
the industry.

\'To do this HVAC units
https://en.wikipedia.org/wiki/HVAC_control_system> use what are called
Start and RUN capacitors.

# *A Start Capacitor* holds an extra charge to start a motor moving.
# *A Run Capacitor* keeps a motor running smoothly with no up and down
spikes.\'

I don\'t find those phrases in the above link.

One of the nice things about Wikipedia is any significant factual statement is supposed to be supported by a reference. I\'d like to see the references for those statements.

The way they describe the start and run caps you would think the same part could do both jobs.

--

Rick C.

+ Get 1,000 miles of free Supercharging
+ Tesla referral code - https://ts.la/richard11209

 

[amdx]

On 7/17/2020 12:39 PM, Ricketty C wrote:

On Friday, July 17, 2020 at 1:14:34 PM UTC-4, amdx wrote:
On 7/17/2020 11:48 AM, Ricketty C wrote:
On Friday, July 17, 2020 at 12:27:17 PM UTC-4, amdx wrote:
*What exactly is the Work of Start Capacitor?*

For single-phase motors normally have both the run and start capacitor.
However, they work differently. The start capacitor produces a bolt of
energy to the motor for it to run; while for run capacitor helps
maintain the functioning of the motor when the start capacitor switches
off. Start capacitor has the ability to store more charge than the run
capacitor.

Something else to observe with a start capacitor is getting burn out
since they work is to accumulate energy to speedily burst it out to
start the motor. How can you tell if the start capacitor is bad? You can
identify through two signs. First, when your motor is not starting after
you ignite it as usual, or if it takes longer than expected to respond.
It means the start capacitor is dead or almost to go bad completely.

https://understanding-air-compressors.com/compressor-capacitors/
 My explanation would be, the run capacitor causes a phase shift of the
current in the start winding, this in relationship to the main winding
cause an increase in torque to start the motor.

I think they are using more of a DC analogy, that I don\'t think applies.
I agree that the person who wrote this web page doesn\'t really understand the function of a start capacitor. Talking about \"accumulate energy to speedily burst it out to start the motor\" as you say might make sense in a DC circuit, but not in an AC circuit.

But for most people reading the page to fix their AC this is as much as they need. Bad start capacitor causes symptoms when starting the motor... good enough to replace a $5 part and move on.

This is from a different site,

Others have similar descriptions, It seem that\'s a common description in
the industry.

\'To do this HVAC units
https://en.wikipedia.org/wiki/HVAC_control_system> use what are called
Start and RUN capacitors.

# *A Start Capacitor* holds an extra charge to start a motor moving.
# *A Run Capacitor* keeps a motor running smoothly with no up and down
spikes.\'
I don\'t find those phrases in the above link.

Sorry, that link was in my quote. As I said \" Others have similar
descriptions\"

My quote was from here,

> https://www.hvachowto.com/start-run-capacitor/

                                    Mikek

One of the nice things about Wikipedia is any significant factual statement is supposed to be supported by a reference. I\'d like to see the references for those statements.

The way they describe the start and run caps you would think the same part could do both jobs.

--
This email has been checked for viruses by Avast antivirus software.
https://www.avast.com/antivirus

 

[Ricketty C]

On Friday, July 17, 2020 at 12:27:17 PM UTC-4, amdx wrote:

*What exactly is the Work of Start Capacitor?*

For single-phase motors normally have both the run and start capacitor.
However, they work differently. The start capacitor produces a bolt of
energy to the motor for it to run; while for run capacitor helps
maintain the functioning of the motor when the start capacitor switches
off. Start capacitor has the ability to store more charge than the run
capacitor.

Something else to observe with a start capacitor is getting burn out
since they work is to accumulate energy to speedily burst it out to
start the motor. How can you tell if the start capacitor is bad? You can
identify through two signs. First, when your motor is not starting after
you ignite it as usual, or if it takes longer than expected to respond.
It means the start capacitor is dead or almost to go bad completely.

https://understanding-air-compressors.com/compressor-capacitors/

 My explanation would be, the run capacitor causes a phase shift of the
current in the start winding, this in relationship to the main winding
cause an increase in torque to start the motor.

I think they are using more of a DC analogy, that I don\'t think applies.

I agree that the person who wrote this web page doesn\'t really understand the function of a start capacitor. Talking about \"accumulate energy to speedily burst it out to start the motor\" as you say might make sense in a DC circuit, but not in an AC circuit.

But for most people reading the page to fix their AC this is as much as they need. Bad start capacitor causes symptoms when starting the motor... good enough to replace a $5 part and move on.

--

Rick C.

- Get 1,000 miles of free Supercharging
- Tesla referral code - https://ts.la/richard11209

 

[Ricketty C]

On Friday, July 17, 2020 at 1:55:53 PM UTC-4, amdx wrote:

On 7/17/2020 12:39 PM, Ricketty C wrote:
On Friday, July 17, 2020 at 1:14:34 PM UTC-4, amdx wrote:
On 7/17/2020 11:48 AM, Ricketty C wrote:
On Friday, July 17, 2020 at 12:27:17 PM UTC-4, amdx wrote:
*What exactly is the Work of Start Capacitor?*

For single-phase motors normally have both the run and start capacitor.
However, they work differently. The start capacitor produces a bolt of
energy to the motor for it to run; while for run capacitor helps
maintain the functioning of the motor when the start capacitor switches
off. Start capacitor has the ability to store more charge than the run
capacitor.

Something else to observe with a start capacitor is getting burn out
since they work is to accumulate energy to speedily burst it out to
start the motor. How can you tell if the start capacitor is bad? You can
identify through two signs. First, when your motor is not starting after
you ignite it as usual, or if it takes longer than expected to respond.
It means the start capacitor is dead or almost to go bad completely.

https://understanding-air-compressors.com/compressor-capacitors/
 My explanation would be, the run capacitor causes a phase shift of the
current in the start winding, this in relationship to the main winding
cause an increase in torque to start the motor.

I think they are using more of a DC analogy, that I don\'t think applies.
I agree that the person who wrote this web page doesn\'t really understand the function of a start capacitor. Talking about \"accumulate energy to speedily burst it out to start the motor\" as you say might make sense in a DC circuit, but not in an AC circuit.

But for most people reading the page to fix their AC this is as much as they need. Bad start capacitor causes symptoms when starting the motor.... good enough to replace a $5 part and move on.

This is from a different site,

Others have similar descriptions, It seem that\'s a common description in
the industry.

\'To do this HVAC units
https://en.wikipedia.org/wiki/HVAC_control_system> use what are called
Start and RUN capacitors.

# *A Start Capacitor* holds an extra charge to start a motor moving.
# *A Run Capacitor* keeps a motor running smoothly with no up and down
spikes.\'
I don\'t find those phrases in the above link.

Sorry, that link was in my quote. As I said \" Others have similar
descriptions\"

My quote was from here,

https://www.hvachowto.com/start-run-capacitor/

                                    Mikek



One of the nice things about Wikipedia is any significant factual statement is supposed to be supported by a reference. I\'d like to see the references for those statements.

The way they describe the start and run caps you would think the same part could do both jobs.

I\'m not a motor guy, but I don\'t recall a \"run\" capacitor. Reading your reference they talk about the two functions of capacitors, then talk about them being combined in one package.

\"A dual capacitor will most often have one side to start the compressor (Herm) and the other side to start the condensing fan motor. The third single leg on a dual capacitor is a shared common leg.\"

So which is it, one start and one run capacitor or start for two motors?

I think it is the latter. My (limited) understanding is that the start capacitor shifts the phase of the AC current for a motor winding that allows the motor to ramp up to speed and when a centrifugal switch removes the cap at higher RPM the winding just becomes part of the regular motor windings allowing the motor to run at highest efficiency.

As Larkin mentioned, on smaller motors where efficiency is often not so important a shading winding is used to permanently provide this starting torque resulting in some loss of effiency.

--

Rick C.

+- Get 1,000 miles of free Supercharging
+- Tesla referral code - https://ts.la/richard11209

 

[Ricketty C]

On Friday, July 17, 2020 at 1:55:53 PM UTC-4, amdx wrote:

On 7/17/2020 12:39 PM, Ricketty C wrote:
On Friday, July 17, 2020 at 1:14:34 PM UTC-4, amdx wrote:
On 7/17/2020 11:48 AM, Ricketty C wrote:
On Friday, July 17, 2020 at 12:27:17 PM UTC-4, amdx wrote:
*What exactly is the Work of Start Capacitor?*

For single-phase motors normally have both the run and start capacitor.
However, they work differently. The start capacitor produces a bolt of
energy to the motor for it to run; while for run capacitor helps
maintain the functioning of the motor when the start capacitor switches
off. Start capacitor has the ability to store more charge than the run
capacitor.

Something else to observe with a start capacitor is getting burn out
since they work is to accumulate energy to speedily burst it out to
start the motor. How can you tell if the start capacitor is bad? You can
identify through two signs. First, when your motor is not starting after
you ignite it as usual, or if it takes longer than expected to respond.
It means the start capacitor is dead or almost to go bad completely.

https://understanding-air-compressors.com/compressor-capacitors/
 My explanation would be, the run capacitor causes a phase shift of the
current in the start winding, this in relationship to the main winding
cause an increase in torque to start the motor.

I think they are using more of a DC analogy, that I don\'t think applies.
I agree that the person who wrote this web page doesn\'t really understand the function of a start capacitor. Talking about \"accumulate energy to speedily burst it out to start the motor\" as you say might make sense in a DC circuit, but not in an AC circuit.

But for most people reading the page to fix their AC this is as much as they need. Bad start capacitor causes symptoms when starting the motor.... good enough to replace a $5 part and move on.

This is from a different site,

Others have similar descriptions, It seem that\'s a common description in
the industry.

\'To do this HVAC units
https://en.wikipedia.org/wiki/HVAC_control_system> use what are called
Start and RUN capacitors.

# *A Start Capacitor* holds an extra charge to start a motor moving.
# *A Run Capacitor* keeps a motor running smoothly with no up and down
spikes.\'
I don\'t find those phrases in the above link.

Sorry, that link was in my quote. As I said \" Others have similar
descriptions\"

My quote was from here,

https://www.hvachowto.com/start-run-capacitor/

                                    Mikek



One of the nice things about Wikipedia is any significant factual statement is supposed to be supported by a reference. I\'d like to see the references for those statements.

The way they describe the start and run caps you would think the same part could do both jobs.

I\'m not a motor guy, but I don\'t recall a \"run\" capacitor. Reading your reference they talk about the two functions of capacitors, then talk about them being combined in one package.

\"A dual capacitor will most often have one side to start the compressor (Herm) and the other side to start the condensing fan motor. The third single leg on a dual capacitor is a shared common leg.\"

So which is it, one start and one run capacitor or start for two motors?

I think it is the latter. My (limited) understanding is that the start capacitor shifts the phase of the AC current for a motor winding that allows the motor to ramp up to speed and when a centrifugal switch removes the cap at higher RPM the winding just becomes part of the regular motor windings allowing the motor to run at highest efficiency.

As Larkin mentioned, on smaller motors where efficiency is often not so important a shading winding is used to permanently provide this starting torque resulting in some loss of effiency.

--

Rick C.

+- Get 1,000 miles of free Supercharging
+- Tesla referral code - https://ts.la/richard11209

 

[Tim Williams]

Poorly written at least.

An AC steady state analysis is sufficient to describe operation. All that\'s
needed is a rotating magnetic field.

Single phase motors (of appropriate design) can operate without a run
capacitor, because the pulsating field can be expressed as the superposition
of two counterrotating stator fields; the rotor only responds to the one
closest in frequency. Single phase motors cannot start from stationary, for
the same reason, and for that a start winding (and sometimes capacitor as
well) is employed. The winding has phase-shifted current/EMF, thus forcing
the rotor in a preferred direction.

For a capacitor employed in such an application, energy storage is of course
necessary, but not so much \"why we do it\".

Tim

--
Seven Transistor Labs, LLC
Electrical Engineering Consultation and Design
Website: https://www.seventransistorlabs.com/

\"amdx\" <amdx@knology.net> wrote in message
news:resjgu$85c$1@dont-email.me...

*What exactly is the Work of Start Capacitor?*

For single-phase motors normally have both the run and start capacitor.
However, they work differently. The start capacitor produces a bolt of
energy to the motor for it to run; while for run capacitor helps maintain
the functioning of the motor when the start capacitor switches off. Start
capacitor has the ability to store more charge than the run capacitor.

Something else to observe with a start capacitor is getting burn out since
they work is to accumulate energy to speedily burst it out to start the
motor. How can you tell if the start capacitor is bad? You can identify
through two signs. First, when your motor is not starting after you ignite
it as usual, or if it takes longer than expected to respond. It means the
start capacitor is dead or almost to go bad completely.

https://understanding-air-compressors.com/compressor-capacitors/

 My explanation would be, the run capacitor causes a phase shift of the
current in the start winding, this in relationship to the main winding
cause an increase in torque to start the motor.

I think they are using more of a DC analogy, that I don\'t think applies.

Mikek


--
This email has been checked for viruses by Avast antivirus software.
https://www.avast.com/antivirus

 

[Tim Williams]

Poorly written at least.

An AC steady state analysis is sufficient to describe operation. All that\'s
needed is a rotating magnetic field.

Single phase motors (of appropriate design) can operate without a run
capacitor, because the pulsating field can be expressed as the superposition
of two counterrotating stator fields; the rotor only responds to the one
closest in frequency. Single phase motors cannot start from stationary, for
the same reason, and for that a start winding (and sometimes capacitor as
well) is employed. The winding has phase-shifted current/EMF, thus forcing
the rotor in a preferred direction.

For a capacitor employed in such an application, energy storage is of course
necessary, but not so much \"why we do it\".

Tim

--
Seven Transistor Labs, LLC
Electrical Engineering Consultation and Design
Website: https://www.seventransistorlabs.com/

\"amdx\" <amdx@knology.net> wrote in message
news:resjgu$85c$1@dont-email.me...

*What exactly is the Work of Start Capacitor?*

For single-phase motors normally have both the run and start capacitor.
However, they work differently. The start capacitor produces a bolt of
energy to the motor for it to run; while for run capacitor helps maintain
the functioning of the motor when the start capacitor switches off. Start
capacitor has the ability to store more charge than the run capacitor.

Something else to observe with a start capacitor is getting burn out since
they work is to accumulate energy to speedily burst it out to start the
motor. How can you tell if the start capacitor is bad? You can identify
through two signs. First, when your motor is not starting after you ignite
it as usual, or if it takes longer than expected to respond. It means the
start capacitor is dead or almost to go bad completely.

https://understanding-air-compressors.com/compressor-capacitors/

 My explanation would be, the run capacitor causes a phase shift of the
current in the start winding, this in relationship to the main winding
cause an increase in torque to start the motor.

I think they are using more of a DC analogy, that I don\'t think applies.

Mikek


--
This email has been checked for viruses by Avast antivirus software.
https://www.avast.com/antivirus

 

[server]

On Fri, 17 Jul 2020 11:27:08 -0500, amdx <amdx@knology.net> wrote:

*What exactly is the Work of Start Capacitor?*

For single-phase motors normally have both the run and start capacitor.
However, they work differently. The start capacitor produces a bolt of
energy to the motor for it to run; while for run capacitor helps
maintain the functioning of the motor when the start capacitor switches
off. Start capacitor has the ability to store more charge than the run
capacitor.

Something else to observe with a start capacitor is getting burn out
since they work is to accumulate energy to speedily burst it out to
start the motor. How can you tell if the start capacitor is bad? You can
identify through two signs. First, when your motor is not starting after
you ignite it as usual, or if it takes longer than expected to respond.
It means the start capacitor is dead or almost to go bad completely.

https://understanding-air-compressors.com/compressor-capacitors/

 My explanation would be, the run capacitor causes a phase shift of the
current in the start winding, this in relationship to the main winding
cause an increase in torque to start the motor.

I think they are using more of a DC analogy, that I don\'t think applies.

Mikek

An single-phase induction motor can run without a run cap, but only
near synchronous speed. It needs a start cap or a shading ring to spin
up from start. Once it\'s going, the start cap can be disconnected.
Start caps are sometimes cheap electrolytics that die eventually.



--

John Larkin Highland Technology, Inc

Science teaches us to doubt.

Claude Bernard

 

[amdx]

On 7/17/2020 1:06 PM, Ricketty C wrote:

On Friday, July 17, 2020 at 1:55:53 PM UTC-4, amdx wrote:
On 7/17/2020 12:39 PM, Ricketty C wrote:
On Friday, July 17, 2020 at 1:14:34 PM UTC-4, amdx wrote:
On 7/17/2020 11:48 AM, Ricketty C wrote:
On Friday, July 17, 2020 at 12:27:17 PM UTC-4, amdx wrote:
*What exactly is the Work of Start Capacitor?*

For single-phase motors normally have both the run and start capacitor.
However, they work differently. The start capacitor produces a bolt of
energy to the motor for it to run; while for run capacitor helps
maintain the functioning of the motor when the start capacitor switches
off. Start capacitor has the ability to store more charge than the run
capacitor.

Something else to observe with a start capacitor is getting burn out
since they work is to accumulate energy to speedily burst it out to
start the motor. How can you tell if the start capacitor is bad? You can
identify through two signs. First, when your motor is not starting after
you ignite it as usual, or if it takes longer than expected to respond.
It means the start capacitor is dead or almost to go bad completely.

https://understanding-air-compressors.com/compressor-capacitors/
 My explanation would be, the run capacitor causes a phase shift of the
current in the start winding, this in relationship to the main winding
cause an increase in torque to start the motor.

I think they are using more of a DC analogy, that I don\'t think applies.
I agree that the person who wrote this web page doesn\'t really understand the function of a start capacitor. Talking about \"accumulate energy to speedily burst it out to start the motor\" as you say might make sense in a DC circuit, but not in an AC circuit.

But for most people reading the page to fix their AC this is as much as they need. Bad start capacitor causes symptoms when starting the motor... good enough to replace a $5 part and move on.

This is from a different site,

Others have similar descriptions, It seem that\'s a common description in
the industry.

\'To do this HVAC units
https://en.wikipedia.org/wiki/HVAC_control_system> use what are called
Start and RUN capacitors.

# *A Start Capacitor* holds an extra charge to start a motor moving.
# *A Run Capacitor* keeps a motor running smoothly with no up and down
spikes.\'
I don\'t find those phrases in the above link.
Sorry, that link was in my quote. As I said \" Others have similar
descriptions\"

My quote was from here,

https://www.hvachowto.com/start-run-capacitor/
                                    Mikek


One of the nice things about Wikipedia is any significant factual statement is supposed to be supported by a reference. I\'d like to see the references for those statements.

The way they describe the start and run caps you would think the same part could do both jobs.
I\'m not a motor guy, but I don\'t recall a \"run\" capacitor. Reading your reference they talk about the two functions of capacitors, then talk about them being combined in one package.

\"A dual capacitor will most often have one side to start the compressor (Herm) and the other side to start the condensing fan motor. The third single leg on a dual capacitor is a shared common leg.\"

So which is it, one start and one run capacitor or start for two motors?

  Ahh, many combinations, Most AC units have a  dual capacitor, one for
the compressor and one for the fan.

Some motors have a start capacitor and a centrifugal switch to open the
circuit to the start winding.

This site looks like a pretty good explanation ,

> https://www.brighthubengineering.com/diy-electronics-devices/44951-learn-about-capacitor-start-induction-run-motors/

This video starts at the point he inspects the centrifugal mechanism and
the switch it opens. 30 seconds will tell you the operation.

> https://youtu.be/vsXeg3xxhP4?t=267

                              Mikek

I think it is the latter. My (limited) understanding is that the start capacitor shifts the phase of the AC current for a motor winding that allows the motor to ramp up to speed and when a centrifugal switch removes the cap at higher RPM the winding just becomes part of the regular motor windings allowing the motor to run at highest efficiency.

As Larkin mentioned, on smaller motors where efficiency is often not so important a shading winding is used to permanently provide this starting torque resulting in some loss of effiency.

--
This email has been checked for viruses by Avast antivirus software.
https://www.avast.com/antivirus

 

[amdx]

On 7/17/2020 1:06 PM, Ricketty C wrote:

On Friday, July 17, 2020 at 1:55:53 PM UTC-4, amdx wrote:
On 7/17/2020 12:39 PM, Ricketty C wrote:
On Friday, July 17, 2020 at 1:14:34 PM UTC-4, amdx wrote:
On 7/17/2020 11:48 AM, Ricketty C wrote:
On Friday, July 17, 2020 at 12:27:17 PM UTC-4, amdx wrote:
*What exactly is the Work of Start Capacitor?*

For single-phase motors normally have both the run and start capacitor.
However, they work differently. The start capacitor produces a bolt of
energy to the motor for it to run; while for run capacitor helps
maintain the functioning of the motor when the start capacitor switches
off. Start capacitor has the ability to store more charge than the run
capacitor.

Something else to observe with a start capacitor is getting burn out
since they work is to accumulate energy to speedily burst it out to
start the motor. How can you tell if the start capacitor is bad? You can
identify through two signs. First, when your motor is not starting after
you ignite it as usual, or if it takes longer than expected to respond.
It means the start capacitor is dead or almost to go bad completely.

https://understanding-air-compressors.com/compressor-capacitors/
 My explanation would be, the run capacitor causes a phase shift of the
current in the start winding, this in relationship to the main winding
cause an increase in torque to start the motor.

I think they are using more of a DC analogy, that I don\'t think applies.
I agree that the person who wrote this web page doesn\'t really understand the function of a start capacitor. Talking about \"accumulate energy to speedily burst it out to start the motor\" as you say might make sense in a DC circuit, but not in an AC circuit.

But for most people reading the page to fix their AC this is as much as they need. Bad start capacitor causes symptoms when starting the motor... good enough to replace a $5 part and move on.

This is from a different site,

Others have similar descriptions, It seem that\'s a common description in
the industry.

\'To do this HVAC units
https://en.wikipedia.org/wiki/HVAC_control_system> use what are called
Start and RUN capacitors.

# *A Start Capacitor* holds an extra charge to start a motor moving.
# *A Run Capacitor* keeps a motor running smoothly with no up and down
spikes.\'
I don\'t find those phrases in the above link.
Sorry, that link was in my quote. As I said \" Others have similar
descriptions\"

My quote was from here,

https://www.hvachowto.com/start-run-capacitor/
                                    Mikek


One of the nice things about Wikipedia is any significant factual statement is supposed to be supported by a reference. I\'d like to see the references for those statements.

The way they describe the start and run caps you would think the same part could do both jobs.
I\'m not a motor guy, but I don\'t recall a \"run\" capacitor. Reading your reference they talk about the two functions of capacitors, then talk about them being combined in one package.

\"A dual capacitor will most often have one side to start the compressor (Herm) and the other side to start the condensing fan motor. The third single leg on a dual capacitor is a shared common leg.\"

So which is it, one start and one run capacitor or start for two motors?

  Ahh, many combinations, Most AC units have a  dual capacitor, one for
the compressor and one for the fan.

Some motors have a start capacitor and a centrifugal switch to open the
circuit to the start winding.

This site looks like a pretty good explanation ,

> https://www.brighthubengineering.com/diy-electronics-devices/44951-learn-about-capacitor-start-induction-run-motors/

This video starts at the point he inspects the centrifugal mechanism and
the switch it opens. 30 seconds will tell you the operation.

> https://youtu.be/vsXeg3xxhP4?t=267

                              Mikek

I think it is the latter. My (limited) understanding is that the start capacitor shifts the phase of the AC current for a motor winding that allows the motor to ramp up to speed and when a centrifugal switch removes the cap at higher RPM the winding just becomes part of the regular motor windings allowing the motor to run at highest efficiency.

As Larkin mentioned, on smaller motors where efficiency is often not so important a shading winding is used to permanently provide this starting torque resulting in some loss of effiency.

--
This email has been checked for viruses by Avast antivirus software.
https://www.avast.com/antivirus

 

[amdx]

On 7/17/2020 1:06 PM, Ricketty C wrote:

On Friday, July 17, 2020 at 1:55:53 PM UTC-4, amdx wrote:
On 7/17/2020 12:39 PM, Ricketty C wrote:
On Friday, July 17, 2020 at 1:14:34 PM UTC-4, amdx wrote:
On 7/17/2020 11:48 AM, Ricketty C wrote:
On Friday, July 17, 2020 at 12:27:17 PM UTC-4, amdx wrote:
*What exactly is the Work of Start Capacitor?*

For single-phase motors normally have both the run and start capacitor.
However, they work differently. The start capacitor produces a bolt of
energy to the motor for it to run; while for run capacitor helps
maintain the functioning of the motor when the start capacitor switches
off. Start capacitor has the ability to store more charge than the run
capacitor.

Something else to observe with a start capacitor is getting burn out
since they work is to accumulate energy to speedily burst it out to
start the motor. How can you tell if the start capacitor is bad? You can
identify through two signs. First, when your motor is not starting after
you ignite it as usual, or if it takes longer than expected to respond.
It means the start capacitor is dead or almost to go bad completely.

https://understanding-air-compressors.com/compressor-capacitors/
 My explanation would be, the run capacitor causes a phase shift of the
current in the start winding, this in relationship to the main winding
cause an increase in torque to start the motor.

I think they are using more of a DC analogy, that I don\'t think applies.
I agree that the person who wrote this web page doesn\'t really understand the function of a start capacitor. Talking about \"accumulate energy to speedily burst it out to start the motor\" as you say might make sense in a DC circuit, but not in an AC circuit.

But for most people reading the page to fix their AC this is as much as they need. Bad start capacitor causes symptoms when starting the motor... good enough to replace a $5 part and move on.

This is from a different site,

Others have similar descriptions, It seem that\'s a common description in
the industry.

\'To do this HVAC units
https://en.wikipedia.org/wiki/HVAC_control_system> use what are called
Start and RUN capacitors.

# *A Start Capacitor* holds an extra charge to start a motor moving.
# *A Run Capacitor* keeps a motor running smoothly with no up and down
spikes.\'
I don\'t find those phrases in the above link.
Sorry, that link was in my quote. As I said \" Others have similar
descriptions\"

My quote was from here,

https://www.hvachowto.com/start-run-capacitor/
                                    Mikek


One of the nice things about Wikipedia is any significant factual statement is supposed to be supported by a reference. I\'d like to see the references for those statements.

The way they describe the start and run caps you would think the same part could do both jobs.
I\'m not a motor guy, but I don\'t recall a \"run\" capacitor. Reading your reference they talk about the two functions of capacitors, then talk about them being combined in one package.

\"A dual capacitor will most often have one side to start the compressor (Herm) and the other side to start the condensing fan motor. The third single leg on a dual capacitor is a shared common leg.\"

So which is it, one start and one run capacitor or start for two motors?

  Ahh, many combinations, Most AC units have a  dual capacitor, one for
the compressor and one for the fan.

Some motors have a start capacitor and a centrifugal switch to open the
circuit to the start winding.

This site looks like a pretty good explanation ,

> https://www.brighthubengineering.com/diy-electronics-devices/44951-learn-about-capacitor-start-induction-run-motors/

This video starts at the point he inspects the centrifugal mechanism and
the switch it opens. 30 seconds will tell you the operation.

> https://youtu.be/vsXeg3xxhP4?t=267

                              Mikek

I think it is the latter. My (limited) understanding is that the start capacitor shifts the phase of the AC current for a motor winding that allows the motor to ramp up to speed and when a centrifugal switch removes the cap at higher RPM the winding just becomes part of the regular motor windings allowing the motor to run at highest efficiency.

As Larkin mentioned, on smaller motors where efficiency is often not so important a shading winding is used to permanently provide this starting torque resulting in some loss of effiency.

--
This email has been checked for viruses by Avast antivirus software.
https://www.avast.com/antivirus

 

[Michael Terrell]

Some use a Potential Relay to disconnect the starting cap. My well pump and table saw are two examples. The pump has two capacitors, while the smaller saw motor only has a starting cap.

 

[Michael Terrell]

Some use a Potential Relay to disconnect the starting cap. My well pump and table saw are two examples. The pump has two capacitors, while the smaller saw motor only has a starting cap.

 

[Michael Terrell]

There are also \'Hard start kits\' that add an extra cap ant use a potential relay to increase the starting torque.

 

[Michael Terrell]

There are also \'Hard start kits\' that add an extra cap ant use a potential relay to increase the starting torque.

 

[RheillyPhoull]

On 18/07/2020 2:06 am, Ricketty C wrote:

On Friday, July 17, 2020 at 1:55:53 PM UTC-4, amdx wrote:
On 7/17/2020 12:39 PM, Ricketty C wrote:
On Friday, July 17, 2020 at 1:14:34 PM UTC-4, amdx wrote:
On 7/17/2020 11:48 AM, Ricketty C wrote:
On Friday, July 17, 2020 at 12:27:17 PM UTC-4, amdx wrote:
*What exactly is the Work of Start Capacitor?*

For single-phase motors normally have both the run and start capacitor.
However, they work differently. The start capacitor produces a bolt of
energy to the motor for it to run; while for run capacitor helps
maintain the functioning of the motor when the start capacitor switches
off. Start capacitor has the ability to store more charge than the run
capacitor.

Something else to observe with a start capacitor is getting burn out
since they work is to accumulate energy to speedily burst it out to
start the motor. How can you tell if the start capacitor is bad? You can
identify through two signs. First, when your motor is not starting after
you ignite it as usual, or if it takes longer than expected to respond.
It means the start capacitor is dead or almost to go bad completely.

https://understanding-air-compressors.com/compressor-capacitors/
 My explanation would be, the run capacitor causes a phase shift of the
current in the start winding, this in relationship to the main winding
cause an increase in torque to start the motor.

I think they are using more of a DC analogy, that I don\'t think applies.
I agree that the person who wrote this web page doesn\'t really understand the function of a start capacitor. Talking about \"accumulate energy to speedily burst it out to start the motor\" as you say might make sense in a DC circuit, but not in an AC circuit.

But for most people reading the page to fix their AC this is as much as they need. Bad start capacitor causes symptoms when starting the motor... good enough to replace a $5 part and move on.

This is from a different site,

Others have similar descriptions, It seem that\'s a common description in
the industry.

\'To do this HVAC units
https://en.wikipedia.org/wiki/HVAC_control_system> use what are called
Start and RUN capacitors.

# *A Start Capacitor* holds an extra charge to start a motor moving.
# *A Run Capacitor* keeps a motor running smoothly with no up and down
spikes.\'
I don\'t find those phrases in the above link.

Sorry, that link was in my quote. As I said \" Others have similar
descriptions\"

My quote was from here,

https://www.hvachowto.com/start-run-capacitor/

                                    Mikek



One of the nice things about Wikipedia is any significant factual statement is supposed to be supported by a reference. I\'d like to see the references for those statements.

The way they describe the start and run caps you would think the same part could do both jobs.

I\'m not a motor guy, but I don\'t recall a \"run\" capacitor. Reading your reference they talk about the two functions of capacitors, then talk about them being combined in one package.

\"A dual capacitor will most often have one side to start the compressor (Herm) and the other side to start the condensing fan motor. The third single leg on a dual capacitor is a shared common leg.\"

So which is it, one start and one run capacitor or start for two motors?

I think it is the latter. My (limited) understanding is that the start capacitor shifts the phase of the AC current for a motor winding that allows the motor to ramp up to speed and when a centrifugal switch removes the cap at higher RPM the winding just becomes part of the regular motor windings allowing the motor to run at highest efficiency.

As Larkin mentioned, on smaller motors where efficiency is often not so important a shading winding is used to permanently provide this starting torque resulting in some loss of effiency.

A run cap is very real in the larger horsepower motors, it adds to the
current when running and also there are fractional hp motors that use a
run cap, many air con units have such for the circulating fan.