Hioki PW3390 - Chapter 11 Maintenance and Service

10.6 Calculation Formula Specifications
211
10
10
Chapter 10 Specifications
(i) : Measurement channel
M : Number of synchronous samples
s : Sample (data point) number
1P2W 1P3W 3P3W2M 3P3W3M 3P4W
Current RMS
Current MEAN
Current AC
component
Current simple
average
Current
fundamental wave
component
Harmonic current I1(i) in harmonic calculation formulas
Peak current
THD Current
Percentage
Ithd(i) in harmonic calculation formulas
Current ripple rate
Current unbalance
factor

Items
Phase
System
Irms
i
1
M
-----I
is

2
S0=
M1–

=
Irms
12
1
2
--- Irms
1
Irms
2
+=
Irms
34
1
2
--- Irms
3
Irms
4
+=
Irms
123
1
3
--- Irms
1
Irms
2
Irms
3
++=
Imn
i

22
----------
1
M
-----I
i
s
S0=
M1–

=
Imn
12
1
2
---Imn
1
Imn
2
+=
Imn
34
1
2
---Imn
3
Imn
4
+=
Imn
123
1
3
---Imn
1
Imn
2
Imn
3
++=
Iac
i
Irms
i

2
Idc
i

2
–=
Idc
i
1
M
-----I
i
s
s0=
M1–

=
Maximum M value
pk sI (i) I(i)  
Minimum M value
pk sI (i) I(i)  
()
100
(2 ( ) )
pk pk
dc
I (i) I (i)
Ii
  


Iunb
123
136  ––
136
 –+
----------------------------- 1 0 0=

I
12
4
I
23
4
I
31
4
++
I
12
2
I
23
2
I
31
2
++
2
------------------------------------------=
I
12
, I
23
, and I
31
are fundamental rms currents
(between lines) obtain from harmonic calcu-
lations. For 3P3W3M and 3P4W systems,
these are converted to current between lines
for calculations.