Hioki PW3336-01, Instruction Manual

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3.5 Measuring Efficiency
78
The instrument can calculate the ratio of active power values for different wires and display the result as the
efficiency
η
[%]. This function can be used to measure the efficiency across inputs and outputs of devices
such as power supply equipment and inverters.
This section details the wiring modes for which efficiency can be measured as well as the calculation formulas
used.
3.5 Measuring Efficiency
When performing synchronized measurement using two instruments, efficiency cannot be
measured between the two instruments. Efficiency can only be measured on a single instru-
ment between the wires listed below.
Wiring mode Efficiency calculation formula Description
1P2W×2
η
1=|P2|/|P1|×100 [%]
The ratio of the CH2 (1-phase/2-wire) active power to the
CH1 (1-phase/2-wire) active power
η
2=|P1|/|P2|×100 [%]
The ratio of the CH1 (1-phase/2-wire) active power to the
CH2 (1-phase/2-wire) active power
Wiring mode Efficiency calculation formula Description
1P2W×3
η
1=|P3|/|P1|×100 [%]
The ratio of the CH3 (1-phase/2-wire) active power to the
CH1 (1-phase/2-wire) active power
η
2=|P1|/|P3|×100 [%]
The ratio of the CH1 (1-phase/2-wire) active power to the
CH3 (1-phase/2-wire) active power
1P3W&1P2W
η
1=|P3|/|Psum|×100 [%]
The ratio of the CH3 (1-phase/2-wire) active power to the
sum of the CH1 and CH2 (1-phase/2-wire) active power
η
2=|Psum|/|P3|×100 [%]
The ratio of the sum of the CH1 and CH2 (1-phase/3-wire)
active power to the CH3 (1-phase/2-wire) active power
3P3W&1P2W
η
1=|P3|/|Psum|×100 [%]
The ratio of the CH3 (1-phase/2-wire) active power to the
sum of the CH1 and CH2 (3-phase/3-wire) active power
η
2=|Psum|/|P3|×100 [%]
The ratio of the sum of the CH1 and CH2 (3-phase/3-wire)
active power to the CH3 (1-phase/2-wire) active power
• Efficiency values
η
1 and
η
2 are calculated from the (absolute values of the) active power values with the
AC+DC rectifier.
• The display range is 0.00 [%] to 200.00 [%]. Results that exceed this range will trigger the over-range dis-
play [ o.r ].
• If the active power value being used as the numerator or denominator in the calculation equation is [ o.r ],
or the active power value being used as the denominator is 0, the efficiency will be displayed as [ o.r ].
• The invalid data display [ - - - - - ] will be shown for wiring modes for which efficiency measurement is not
performed, for example 3V3A, 3P3W3M, 3P4W, etc.