300
Measurement of main circuit voltages,
currents and powers
6.2.2 Measurement of powers
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6.2.3 Measurement of voltages and use of PT
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3-wattmeter method (Electro-dynamometer type)
2-wattmeter method (Electro-dynamometer type)
Clip AC power meter
(For balanced three-phase load)
Clamp-on wattmeter
(Hall device power arithmetic type)
0 20 40 60 80 100 120Hz
60
80
100
120
%
3-wattmeter method (Electro-dynamometer type)
2-wattmeter method (Electro-dynamometer type)
Clip AC power meter
(For balanced three-phase load)
Clamp-on wattmeter
(Hall device power arithmetic type)
0 20 40 60 80 100 120Hz
60
80
100
120
%