120/208 Single Phase Power Calculations

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Besoeker3

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Your obsession with this terminological detail crossed the line from being informative to being annoying a long time ago.

Cheers, Wayne
I don't think it is a detail when it is simply inaccurate.
GoldDigger has already pointed this out.
 

wwhitney

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I don't think it is a detail when it is simply inaccurate.
Terminology is conventional and may choose to emphasize different aspects. As there are no utilization loads I am aware of that depend on the phase difference between the two L-N legs of a 120/208V system, such a system only supplies single phase loads. So in this case, the terminology is based on what the system actually does in practice, not what it could do in theory. It is not up to you or me to decree that the terminology has to be based on the underlying physics.

If it makes you happy, when you see "120/208V single phase" just insert the word loading as you read it to yourself, as in "120/208V single phase (loading)". Or perhaps "120/208V single phase (loading; 2 of 3 phases physics)." That information is understood by any knowledgeable reader.

Cheers, Wayne
 

Besoeker3

Senior Member
Location
UK
Occupation
Electrical Engineer
Terminology is conventional and may choose to emphasize different aspects. As there are no utilization loads I am aware of that depend on the phase difference between the two L-N legs of a 120/208V system, such a system only supplies single phase loads. So in this case, the terminology is based on what the system actually does in practice, not what it could do in theory. It is not up to you or me to decree that the terminology has to be based on the underlying physics.

If it makes you happy, when you see "120/208V single phase" just insert the word loading as you read it to yourself, as in "120/208V single phase (loading)". Or perhaps "120/208V single phase (loading; 2 of 3 phases physics)." That information is understood by any knowledgeable reader.

Cheers, Wayne
I know exactly what it is. Just 208V and 120V are not in phase.
 
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wwhitney

Senior Member
Location
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Retired
I know exactly what it is.
Good, so then you can understand that the name may not depend on the physics, but rather on what type of loads the system is used for. The name can't be accurate for both the loading and the physics, and in this case the convention is to go with the loading. Please recognize the convention.

Cheers, Wayne
 

Besoeker3

Senior Member
Location
UK
Occupation
Electrical Engineer
Good, so then you can understand that the name may not depend on the physics, but rather on what type of loads the system is used for. The name can't be accurate for both the loading and the physics, and in this case the convention is to go with the loading. Please recognize the convention.

Cheers, Wayne
Yes, a convention. But it is not single phase..
 

wwhitney

Senior Member
Location
Berkeley, CA
Occupation
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Yes, a convention. But it is not single phase..
What is is? : - )

I think we've covered that you might call a system "single phase" because it only supports single phase loads. Or you might call it "single phase" because it has only one phase angle present. It's not clear to me that the sentence "the system is single phase" necessarily means the latter rather than the former. I would say it is ambiguous.

Cheers, Wayne
 

Besoeker3

Senior Member
Location
UK
Occupation
Electrical Engineer
What is is? : - )

I think we've covered that you might call a system "single phase" because it only supports single phase loads. Or you might call it "single phase" because it has only one phase angle present. It's not clear to me that the sentence "the system is single phase" necessarily means the latter rather than the former. I would say it is ambiguous.

Cheers, Wayne
Yes,, one phase angle. How else could you describe it?
 

Besoeker3

Senior Member
Location
UK
Occupation
Electrical Engineer
As we've been discussing, by the type of loads the system supplies, and how many phase angles they require.

Cheers, Wayne
Thus many phases would not be single phase.................:)
 
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