Does volt amps = watts?

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brian john said:
This should explain it adequately.

MYPLATES.jpg
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Best license plates ever! :)
 
So we have confused the man with all this technical terms but no one has explained the RMS to him..The more I learn the less I know..Root mean square..confused now..:grin: :D
 
K2500 said:
So would a 1500W heater installed in a plant with a PF of .9 only draw 1350w?
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No. A heater would have no power factor as it is purely resistive load. Inductive loads such as transformers and induction motors have power factors. Synchronous motrors have no power factors either, so they are used sometimes to correct power factors in the plants.
 
weressl said:
No. A heater would have no power factor as it is purely resistive load. Inductive loads such as transformers and induction motors have power factors. Synchronous motrors have no power factors either, so they are used sometimes to correct power factors in the plants.
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I was thinking the overall PF might effect things farther into the system.
Are the synchronous motors used to prevent increasing the lag, or is it common practice to over exite the rotor resulting in a leading(correcting) PF. I'm studing A/C motors now, so understanding theory in practice helps.
 
Strictly speaking:

Strictly speaking:

weressl said:
No. A heater would have no power factor as it is purely resistive load. Inductive loads such as transformers and induction motors have power factors. Synchronous motrors have no power factors either, so they are used sometimes to correct power factors in the plants.
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Lazlo,

I think you misspoke. All loads carry a PF. The PF of a resistive load is 1.0.
 
So we have confused the man with all this technical terms but no one has explained the RMS to him
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I didn't try to understand therefore I didn't get confused.

I just skimmed over it till someone said "in your case, VA=W". That was all I needed to know.

My memory is near capacity and to make more room I'd have figure out a way to delete lyrics of old songs and TV commercials from the 60's.
 
K2500 said:
I was thinking the overall PF might effect things farther into the system.
Are the synchronous motors used to prevent increasing the lag, or is it common practice to over exite the rotor resulting in a leading(correcting) PF. I'm studing A/C motors now, so understanding theory in practice helps.
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Since the synchronous motors are usually large machines and run at unilty (1.0) power factor, they are able to compensate for the sum of many smaller loads power factors. They do so without the resonance/harmonic problems that capacitors may create.

One of the main benefits of the power factor correction is reduced feeder size, since you can deliver the same amount of power but the current component of the P=I*V*Pf will be smaller. Note that the voltage drop will also be smaller.

I had one case where we were feeding 480V on some overhead 500kCMil cables 650' feet away and the load had steadily increased over the years. Power factor correction at the load end enabled us to continue to add loads without needing to add additional, parallel feeder that would have provided more capacity than we needed. (This was a VERY old installation.)
 
rattus said:
Lazlo,

I think you misspoke. All loads carry a PF. The PF of a resistive load is 1.0.
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Yes and no.

Pover FACTOR refers to the leading or lagging current component of the power formula and how that number FACTORS into the result. Neither 0, nor 1 has effect on the result in multiplication.

fac?tor

Pronunciation: (fak'tur), [key]
?n.
1. one of the elements contributing to a particular result or situation: Poverty is only one of the factors in crime.
2. Math.one of two or more numbers, algebraic expressions, or the like, that when multiplied together produce a given product; a divisor: 6 and 3 are factors of 18.
 
"I complained to the Virginian DMV and the relented and re-issued my plates"

Missed your post about the VA DMVs plate faux pas. What did they stamp out origionally?

You must have tired of waiting for the results of Mike's 'rear window' logotype contest.

But now I know how to spot you on the road! Think I'll put the chains on 'ole white' and drive on up!

Best Wishes Everyone in 2008
 
weressl said:
Yes and no.

Pover FACTOR refers to the leading or lagging current component of the power formula and how that number FACTORS into the result. Neither 0, nor 1 has effect on the result in multiplication.

fac?tor

Pronunciation: (fak'tur), [key]
?n.
1. one of the elements contributing to a particular result or situation: Poverty is only one of the factors in crime.
2. Math.one of two or more numbers, algebraic expressions, or the like, that when multiplied together produce a given product; a divisor: 6 and 3 are factors of 18.
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Lazlo, you digress.

You said heaters carry "NO" PF when in fact their PF is 1.0.

I am saying "ALL" loads carry a PF which ranges between 0.0 and 1.0. In general,

Preal = Papp x PF

which you well know.
 
rattus said:
Lazlo, you digress.

You said heaters carry "NO" PF when in fact their PF is 1.0.

I am saying "ALL" loads carry a PF which ranges between 0.0 and 1.0. In general,

Preal = Papp x PF

which you well know.
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No, I don't digress.

di?gress

Pronunciation: (di-gres', dī-), [key]
?v.i.
1. to deviate or wander away from the main topic or purpose in speaking or writing; depart from the principal line of argument, plot, study, etc.


Original quote from me: "No. A heater would have no power factor as it is purely resistive load."

Then I went on to explain that since 1.0 does not change the result of the multiplication, it is not a FACTOR. You can put it in, you can take it away it does not change the value, it is not a FACTOR. As the dictionary explains it, in 3*6=18, the FACTORS are the 6 and 3.
 
weressl said:
Then I went on to explain that since 1.0 does not change the result of the multiplication, it is not a FACTOR.
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I think Rattus would tell you that X and 1 are both factors of X, such as in: X * 1 = X
 
weressl said:
A heater would have no power factor as it is purely resistive load."
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Regardless of any and all bantering, posturing, and digressing, real or perceived, Rattus is correct when he states that the quote above is incorrect.

I guess it could be said that a heater has no "power factor" factor... maybe you could win that argument.:grin:
 
crossman said:
Regardless of any and all bantering, posturing, and digressing, real or perceived, Rattus is correct when he states that the quote above is incorrect.

I guess it could be said that a heater has no "power factor" factor... maybe you could win that argument.:grin:
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Of which FACTOR did you not get the meaning of?:cool:

P=U*I*Pf

U= factor if it is a number greater than 0
I= factor if is is a number greater than 0
Pf= factor if it is a number greater than 0, but less than 1

Argue math if you know math, otherwise just keep yelling:D That' how lawyers argue.
 
weressl said:
No, I don't digress.

di•gress

Pronunciation: (di-gres', dī-), [key]
—v.i.
1. to deviate or wander away from the main topic or purpose in speaking or writing; depart from the principal line of argument, plot, study, etc.


Original quote from me: "No. A heater would have no power factor as it is purely resistive load."

Then I went on to explain that since 1.0 does not change the result of the multiplication, it is not a FACTOR. You can put it in, you can take it away it does not change the value, it is not a FACTOR. As the dictionary explains it, in 3*6=18, the FACTORS are the 6 and 3.
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Lazlo,

Irrespective of the dictionary definitions, PF is defined in engineering texts as follows,

PF = Real Power/Apparent Power = cos(theta)

This range of values clearly includes zero, one, and all numbers in between. Furthermore, there is no requirement for the PF to change the result, although a zero PF would do so. Furthermore, unity PF is mentioned iinnumerable times in engineering discussions, for example you mention unity PF in post #29!
 
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rattus said:
Lazlo,

Irrespective of the dictionary definitions, PF is defined in engineering texts as follows,

PF = Real Power/Apparent Power = cos(theta)

This range of values clearly includes zero, one, and all numbers in between. Furthermore, there is no requirement for the PF to change the result, although a zero PF would do so. Furthermore, unity PF is mentioned iinnumerable times in engineering discussions.
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OK, go ahead and arguew with the mathematicians and the dictionary.

You can't redefine English just because it became misused in the vernacular.

Just like my name remains LASZLO regardless how many times you spell it differently.

It is cosine(fi) not theta.
 
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