Measuring 3 Phase Power Using Wattmeter Methods

AI Thread Summary
Three-phase power can be measured using either the two-wattmeter or three-wattmeter methods, depending on the balance of the phases and the power factor. For balanced loads with a power factor of 1, one can measure the current in one phase and the voltage between two phases. In cases of unbalanced loads, it is necessary to measure the current in each phase along with the phase-to-phase voltages. A wattmeter manual was shared to provide additional wiring configurations for reference. Understanding these methods is crucial for accurate power measurement in three-phase systems.
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Hi all,

3 phase power is measured using 2 and 3 wattmeter methods.Correct?
can someone explain how these 2 work?I cudn get enuf info on it.
 
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This might be helpful.

Regards
 
hey dlgoff

thanx a lot.i shall look into each link and hopefully find what i am loking for and more.
Thanx a loooooot!
 
It depends: if the phases are balanced and the power facter is 1, you could measure the amperage across one phase and voltage between two of them (I think - it might be phase to ground, though). If they aren't, you can measure each phase's amperage and each phase to phase voltage. There's probably a shortcut to that, but I don't remember it. Lemme see if I can dig up a wattmeter wiring diagram...

http://www.amprobe.com/manuals/ampKilowattHourMeter.pdf is a manual for a wattmeter showing different wiring configurations...

I'm a little thin on the different configurations of 3 phase power...
 
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thanx a lot russ,i really needed this.
:smile:
 
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