App-1
IM 760201-01E
Appendix
3
2
1
4
5
6
7
8
9
10
11
12
13
14
App
Index
Appendix 1 Symbols and Determination of
Measurement Functions
Measurement Functions Used in Normal Measurement
Upk
Urms
Ipk
Irms
P
S
cos
–1
( )
P
S
Voltage crest factor CfU =
Current crest factor CfI =
Voltage crest factor: CfU
Current crest factor: CfI
Maximum voltage: U + pk [V]
Minimum voltage: U – pk [V]
Maximum current: I + pk [A]
Minimum current I – pk [A]
The maximum u(n) for every data update
The minimum u(n) for every data update
The maximum i(n) for every data update
The minimum i(n) for every data update
Upk = |U + pk| or |U – pk|
whichever is larger
Ipk = |I + pk| or |I – pk|
whichever is larger
Active power P [W]
Reactive power Q [var] TYPE1,
TYPE2
Apparent power S [VA] TYPE1,
TYPE2
TYPE3
TYPE3
Power factor
λ
Phase difference
φ
[°]
The phase angle can be switched between lead (D)/lag (G) display and 360° display.
See section 5.5 for details.
Methods of Computation and Determination
For information about the symbols in the equations,
see the notes at the end of page App-3.
Voltage frequency: fU (FreqU) [Hz]
Current frequency: fI (FreqI) [Hz]
(Continues on next page)
(Table 1/3)
The two frequencies, fU and fI, can be measured simultaneously from any
installed element. (The PLL source frequency is excluded.)
On models with the frequency measurement add-on option, the fU and fI of all
elements can be measured simultaneously.
S
2
– P
2
s
•
P
2
+ Q
2
Q(k)=Ur(k)
•
Ij(k) – Uj(k)
•
Ir(k)
Ur(k) and Ir(k) are the real number components of U(k) and I(k)
Uj(k) and Ij(k) are the imaginary components of U(k) and I(k)
Valid only when harmonics are being measured correctly.
Q(k)
k = min
max
s is -1 for a lead phase and 1 for a lag phase
True rms value:
Urms
Rectified mean value
calibrated to the rms value: Umn
Rectified mean value:
Urmn
Simple average:
Udc
AC component:
Uac
Measurement Functions
Used in Normal
Measurement
Voltage
U [V]
True rms value:
Irms
Rectified mean value
calibrated to the rms value: Imn
Rectified mean value:
Irmn
Simple average:
Idc
AC component:
Iac
Current
I [A]
Urms
Urmn
Irmn
Umn
Udc
Uac
Irms
Imn
Idc
Iac
AVG[u(n)
2
]
AVG[i(n)
2
]
RMS
2
-DC
2
RMS
2
-DC
2
AVG[ i(n) ]
π
2 2
AVG[ u(n) ]
π
2 2
AVG[ u(n) ]
AVG[ i(n) ]
AVG[u(n)]
AVG[i(n)]
U
•
I
AVG[u(n)
•
i(n) ]
Appendix
