reading amperages

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AKwiring

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This may be a dumb question, but can someone clarify this for me?
If I am measuring the amperage across each leg of a 2 pole 100 amp breaker and one leg reads 60 amps and one reads 50 amps is the service using 55 amps?
or 110 amps?
Can you explain?
Thank you.
 
Dennis Alwon

Dennis Alwon

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AKwiring said:
This may be a dumb question, but can someone clarify this for me?
If I am measuring the amperage across each leg of a 2 pole 100 amp breaker and one leg reads 60 amps and one reads 50 amps is the service using 55 amps?
or 110 amps?
Can you explain?
Thank you.
Click to expand...

Neither -- it is using 60 amps one one leg and 50 amps on the other. I guess you can say it is using a maximum 60 amps.
 
iwire

iwire

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Massachusetts
AKwiring said:
This may be a dumb question, but can someone clarify this for me?
If I am measuring the amperage across each leg of a 2 pole 100 amp breaker and one leg reads 60 amps and one reads 50 amps is the service using 55 amps?
or 110 amps?
Can you explain?
Thank you.
Click to expand...

Because the supply and loads in a panel will be more then one voltage you have to forget current (amps) and think power (watts)

A 100 amp breaker in a 120/240 volt single phase panel can supply 24,000 watts (24 KW) evenly balanced.
 
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winnie

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Springfield, MA, USA
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Electric motor research
iwire said:
A 100 amp breaker in a 120/240 volt single phase panel can supply 24,000 watts (24 KW) evenly balanced.
Click to expand...

And if that breaker is supplying 60A on one leg and 50A on the other leg, then you have 60*120 + 50*120 = 13200 kva being supplied.

-Jon
 
480sparky

480sparky

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Location
Iowegia
winnie said:
And if that breaker is supplying 60A on one leg and 50A on the other leg, then you have 60*120 + 50*120 = 13200 kva being supplied.

-Jon
Click to expand...

Would not 50a on leg B be the same 50a on leg A, the other 10a going back through the neutral?
 
roger

roger

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Fl
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480sparky said:
Would not 50a on leg B be the same 50a on leg A, the other 10a going back through the neutral?
Click to expand...

Yes (barring stray currents) but, neutral current is not power supplied.

Roger
 
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