YOKOGAWA WT3002E - Page 108

7-5
IM WT3001E-51EN
Harmonic Measurement in Normal Measurement Mode (Option)
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Index
• Harmonic Measurement Function That Indicates the Phase Difference (φ) of
the Voltage and Current between the Input Elements
 Therearefiveharmonicmeasurementfunctionsthatexpressthephasedifference(φ).
φUi-Uj,φUi-Uk,φUi-Ii,φUi-Ij,andφUi-Ik
(where i, j, and k are input element numbers)
Explanation is given for the case when the number of installed input elements is 4,
elements1,2,and3areassignedtowiringunitΣAusingathree-phase,four-wire
system. Here i = 1, j = 2, and k = 3.
In this case, the numeric data of the harmonic measurement functions of phase
difference concerning elements 1, 2, and 3 can be determined as shown below.
• φU1-U2
Phase difference of the fundamental voltage U2(1) of element 2 with respect to
the fundamental voltage U1(1) of element 1.
• φU1-U3
Phase difference of the fundamental voltage U3(1) of element 3 with respect to
the fundamental voltage U1(1) of element 1.
• φU1-I1
Phase difference of the fundamental current I1(1) of element 1 with respect to
the fundamental voltage U1(1) of element 1.
• φU1-I2
Phase difference of the fundamental current I2(1) of element 2 with respect to
the fundamental voltage U1(1) of element 1.
• φU1-I3
Phase difference of the fundamental current I3(1) of element 3 with respect to
the fundamental voltage U1(1) of element 1.
If the wiring pattern is set up so that input elements 1 and 2 are assigned to wiring
unitΣAusingathree-phase,three-wiresystemandinputelements3and4are
assignedtowiringunitΣBusingathree-phase,three-wiresystem,thenumeric
data below are determined.
• WiringunitΣA:φU1-U2,φU1-I1,andφU1-I2
• WiringunitΣB:φU3-U4,φU3-I3,andφU3-I4
φU1-U3andφU1-I3arenotdetermined.
• Harmonic Measurement Function of Wiring Units ΣA and ΣB
(Σ Functions)
The following 6 types of harmonic measurement functions are available. For details
on the determination of each measurement function, see section 7.9.
1
Yes
Yes
Yes
Yes
Yes
Yes
UΣ( )
IΣ( )
PΣ( )
SΣ( )
QΣ( )
λΣ( )
Characters or Numbers
in Parentheses
Measurement
function
Yes: Numeric data available
• For measurement functions with parentheses, the value “1” is entered in the
parentheses. This represents the numeric data of the fundamental signal.
7.1 Harmonic Measurement Function