YOKOGAWA WT1800 User Manual page 90

6.3 Displayed Items
Measurement Functions (Σ Functions) Determined for Each Wiring Unit (ΣA, ΣB, and ΣC)
Item
Voltage (V)
Current (A)
Active power (W)
Apparent power (VA)
Reactive power (var)
Power factor
* The total value is determined according to the equation on page App-4 from the fundamental wave (1st order) and all harmonic
components (2nd order to the upper limit of harmonic analysis). The DC component can also be included.
Delta Computation (Option)
Item
Voltage (V)
Current (A)
Power (W)
Waveforms and Trends
Item
Waveform display
Trend display
Bar Graphs and Vectors (Option)
Item
Bar graph display
Vector display
6-6
Symbols and Meanings
UΣ(1): rms voltage of harmonic order 1
IΣ(1): rms current of harmonic order 1
PΣ(1): active power of harmonic order 1
SΣ(1): apparent power of harmonic order 1
QΣ(1): reactive power of harmonic order 1
λΣ(1): power factor of harmonic order 1
Delta Symbols and Meanings
Computation
Setting
difference ΔU1: differential voltage between u1 and u2 determined through computation
3P3W->3V3A ΔU1: unmeasured line voltage computed in a three-phase, three-wire system
DELTA->STAR ΔU1, ΔU2, ΔU3: phase voltage computed in a three-phase, three-wire (3V3A)
system
ΔUΣ = (ΔU1 + ΔU2 + ΔU3)/3
STAR->DELTA ΔU1, ΔU2, ΔU3: line voltage computed in a three-phase, four-wire system
ΔUΣ = (ΔU1 + ΔU2 + ΔU3)/3
difference ΔI: differential current between i1 and i2 determined through computation
3P3W->3V3A ΔI: unmeasured phase current
DELTA->STAR ΔI: neutral line current
STAR->DELTA ΔI: neutral line current
difference —
3P3W->3V3A —
DELTA->STAR ΔP1, ΔP2, ΔP3: phase power computed in a three-phase, three-wire (3V3A)
system
ΔPΣ = ΔP1 + ΔP2 + ΔP3
STAR->DELTA —
Specifications
Displays voltage, current, torque, speed, AUX1, and AUX2 waveforms for elements 1 to 6
Displays a line graph of measurement function numeric data trends
Number of measurement channels: up to 16
Specifications
Displays a bar graph of the amplitude of each harmonic
Displays the phase difference between the fundamental voltage signal and fundamental current
signal as a vector.
*
UΣ: total rms voltage
*
IΣ: total rms current
*
PΣ: total active power
*
SΣ: total apparent power
QΣ: total reactive power *
*
λΣ: total power factor
IM WT1801-03EN