YOKOGAWA WT1803 User Manual

2-6
IM WT1801-01EN
Delta Computation (Δ Measure; option)
The sum or difference of the instantaneous voltage or current values (sampled data) between the elements in
a wiring unit can be used to determine various types of data such as the differential voltage and phase voltage.
This operation is called delta computation.
Types of Delta Computation (ΔMeasure Type)
The following types of delta computation are available:
•
Dif
ferential voltage and differential current (Difference)
• Line voltage and phase current (3P3W > 3V3A)
• Star-delta transformation (Star>Delta)
• Delta-star transformation (Delta>Star)
The delta computation types that you can select vary as indicated below according to the wiring system.
Wiring System Delta Computation Type
1P3W Difference, 3P3W>3V3A
3P3W Difference, 3P3W>3V3A
3P4W Star>Delta
3P3W(3V3A) Delta>Star
• Differential Voltage and Differential Current (Difference)
The differential voltage and differential current between two elements can be computed on a single-phase,
three-wire system or on a three-phase, three-wire system.
When you perform delta computation on wiring unit ΣA, the available measurement functions are as follows.
ΔU1rms[Udif
fA], ΔU1mn[UdiffA], ΔU1dc[UdiffA], ΔU1rmn[UdiffA], ΔU1ac[UdiffA]
ΔIrms[IdiffA], ΔImn[IdiffA], ΔIdc[IdiffA], ΔIrmn[IdiffA], ΔIac[IdiffA]
* In the measurement functions,
rms, mn(mean), dc, rmn(r-mean), and ac are the delta computation modes.
A indicates the wiring unit.
Click here.
• Line Voltage and Phase Current (3P3W > 3V3A)
You can compute unmeasured line voltages and phase currents by converting the data of a three-phase,
three-wire system to the data of the three-voltage, three-current method (3V3A).
T
R
ST
R
S
When you perform delta computation on wiring unit ΣA, the available measurement functions are as follows.
ΔU1rms[UrsA], ΔU1mn[UrsA], ΔU1dc[UrsA], ΔU1rmn[UrsA], ΔU1ac[UrsA]
ΔIrms[ItA], ΔImn[ItA], ΔIdc[ItA], ΔIrmn[ItA], ΔIac[ItA]
±
±
±
±
I
R
S
T
U
U
I
N
I1
I2
U2
U1
Urs
It
* In the measurement functions, rms, mn(mean), dc, rmn(r-mean), and ac are the delta computation modes.
A indicates the wiring unit.
Click here.
2 Fundamental Measurement Conditions

YOKOGAWA WT1803 Specifications

General

Brand	YOKOGAWA
Model	WT1803
Category	Measuring Instruments
Language	English