KW8M Eco-POWER METER (1A/5ACT input type)
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6.1.5 Electricity Charge
・
It displays the standard electricity charge for the integral electrical power.
[CHARGE]
Lighting
*When the value exceeds ‘99999999’, will be displayed.
6.1.6 Power factor
・
It displays the loads’ power factor.
*Before start measuring, select phase and wire system according to the measured load.
When selected system does not meet it, it can not measure correctly. (Refer to the explanation of
setting mode.)
Sample of lagging phase
Sample of leading phase
[cos
φ
]
Lighting
・
How to calculate power factor
Eco-POWER METER displays power factor by calculating as below.
Power factor operation is a method assuming balanced load. The error might be big when it measures
unbalanced load.
Single-phase two-wire
Single-phase three-wire
Three-phase four-wire
1P3W: a=2
3P4W: a=3
Three-phase three-wire
Voltage
ｘ
Current
PF
＝
Instantaneous electric power
a
ｘ
ｘ
PF
＝
Instantaneous electric power
Average of
each phase V
Average of
each phase A
3
ｘ
ｘ
PF
＝
Instantaneous electric power
Average of
each phase V
Average of
each phase A
√
