This method requires only two wattmeters to measure three-phase load for balanced as well as
unbalanced loads. In this method, two wattmeters are connected in two phases and their pressure
coils are connected to the remaining third phase, as shown in Figure 9.17.
Figure 9.17 Two-wattmeter Method of Measuring Power for Star- and
Delta-connected Load
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This method of measurement is useful for balanced and unbalanced loads.
Let us consider the measurement of three-phase power of a star-connected load using two
single-phase wattmeters as ...
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