7-40
IM WT3001E-51EN
Measurement Functions Determined for Each Input Element
Item
Symbol and Meaning
Voltage (V)
U(k): rms value of the harmonic voltage of order k
*1
U: Rms voltage (total value
*2
)
Current (A)
I(k): rms value of the harmonic current of order k
I: Rms current (total value
*2
)
Active power (W)
P(k): Active power of the harmonic signal of order k
P: Active power (total value
*2
)
Apparent power (VA)
S(k): Apparent power of the harmonic signal of order k S: Total apparent power (total value
*2
)
Reactive power (var)
Q(k): Reactive power of the harmonic signal of order k Q: Total reactive power (total value
*2
)
Power factor
λ(k): Power factor of the harmonic signal of order k
λ: Total power factor (total value
*2
)
Phase difference (°)
φ(k): Phase difference between the harmonic voltage and current of order k, φ: total phase
φU(k): Phase difference of each harmonic voltage U(k) with respect to the fundamental signal
U(1)
φI(k): Phase difference of each harmonic current I(k) with respect to the fundamental signal
I(1)
Impedance
*3
(Ω) of the load
circuit
Z(k): Impedance of the load circuit observed by the k
th
order harmonic signal.
Resistance
*3
and reactance
*3
Rs(k): Resistance observed by the k
th
order harmonic signal of the load circuit that has a
resistor R, (Ω) of the load circuit inductor L, and capacitor C connected in series
Xs(k): Reactance observed by the k
th
order harmonic signal of the load circuit that has a
resistor R, inductor L, and capacitor C connected in series
Rp(k): Resistance observed by the k
th
order harmonic signal of the load circuit that has a
resistor R, inductor L, and capacitor C connected in parallel
Xp(k): Reactance observed by the k
th
order harmonic signal of the load circuit that has a
resistor R, inductor L, and capacitor C connected in parallel
Harmonic distortion factor [%]
Uhdf(k): The ratio of the harmonic voltage U(k) to U(1) or U expressed as a percentage.
Ihdf(k): The ratio of the harmonic current I(k) to I(1) or I expressed as a percentage.
Phdf(k): The ratio of the active power P(k) of the harmonic signal to P(1) or P expressed as a
percentage.
Total harmonic distortion [%]
Uthd: The ratio of the total harmonic voltage to U(1) or U
*4
expressed as a percentage.
Ithd: The ratio of the total harmonic current to I(1) or I expressed as a percentage.
Pthd: The ratio of the active power of the total harmonic signal to P(1) or P expressed as a
percentage.
Telephone harmonic factor
*3 *5
Uthf: Voltage telephone harmonic factor, Ithf: Current telephone harmonic factor
(Applicable standard IEC34-1
(1996))
Telephone influence factor
*3 *5
Utif: Voltage telephone influence factor, Itif: Current telephone influence factor
(Applicable standard
IEEE Std 100 (1996))
Harmonic voltage factor
*3 *6
hvf: harmonic voltage factor
Harmonic current factor
*3 *6
hcf: harmonic current factor
*1 Order k is an integer in the range from 0 to the upper limit of the measured order. 0
th
order is the DC component.
The upper limit is determined automatically (maximum is 100
th
) by the frequency of the PLL source.
*2 The total is a value determined according to the equation given on page 7-42 from the fundamental signal (1
st
order) and all harmonic components (2
nd
to the upper limit of the measured order). The DC component can
also be included. The total value cannot be measured with the harmonic measurement in normal measurement
mode.
*3 Cannot be measured in IEC harmonic measurement mode.
*4 Total harmonic is a value determined according to the equation given in the next section from all harmonic
components (2
nd
to the upper limit of measured order).
*5 Measurement functions specific to the IEC or IEEE standard.
*6 The equation may vary depending on the definitions given in the respective standard. For details, see the
respective standard.
7.11 Harmonic Measurement Specifications
