Fluke 43B - Measuring Power Factor of 3-Phase Motors; Grounded Y-Connection with Balanced Load

Motor Loads
Induction Motors
4
47
Measuring Power Factor of 3-Phase Motors
A power factor with a value close to 1 means that nearly all supplied power is
consumed by the motor. A power factor of less than 1 results in extra currents,
called reactive currents. This requires larger power lines and transformers.
Also there will be more power loss in the transmission lines.
Grounded Y-Connection with Balanced Load
For balanced motors with a grounded Y-connection, you can read the Power
Factor directly from the screen. To test for a grounded Y, simply check the
three phase-to-ground voltages. If the voltages are stable and equal, then the
system is wired as a grounded Y. Measure Power Factor as follows:
1 Open the main menu.
2
3
Make connections as shown below. Run the motor under normal full
load (power factor decreases at less than full load).
 Observe the Power Factor.
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 POWER
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