User Manual

85
16.1.2.3. DC quantities (neutral included except Vdc and Udc – reassessment every second)
Phase-to-ground DC voltage of phase (i+1) with i ∈ [0; 2]
[ ] [ ][ ]
∑
−
=
⋅=
1
0
1
Vdc
NechSec
n
niV
NechSec
i
Phase-to-phase DC voltage of phase (i+1) with i ∈ [0 ; 2]
[ ] [ ][ ]
∑
−
=
⋅=
1
0
1
Udc
NechSec
n
niU
NechSec
i
DC current of phase (i+1) with i ∈ [0; 3] (i = 3 ∈ neutral current)
[ ] [ ][ ]
∑
−
=
⋅=
1
0
1
Adc
NechSec
n
niA
NechSec
i
Remark: The value NechSec is the number of samples per second.
16.1.2.4. Severity of Short-term flicker – 10 minutes (excluding neutral)
Method based on the IEC61000-4-15 standard.
The input values are half-period RMS voltages (phase-to-neutral for distribution systems with neutral, phase-to-phase for distribu-
tion systems without neutral). Blocks 3 and 4 are generated digitally. The classifier of block 5 has 128 levels.
The value of PST[i] is updated every 10 minutes (phase (i+1) with i ∈ [0; 2]).
Note: The user can reset the PST calculation by pressing the

key in the Summary mode. It is important to note that the
10-minute intervals do not necessarily start on an integer multiple of 10 minutes of universal time coordinated (UTC).
16.1.2.5. Peak values (neutral included except Vpp, Upp, Vpm and Upm – reassessment every second
Positive and negative phase-to-neutral peak voltages of phase (i+1) with i ∈ [0; 2].
Vpp[i] = max(V[i][n]), Vpm[i] = min(V[i][n]) n ∈ [0; N]
Positive and negative phase-to-phase peak voltages of phase (i+1) with i ∈ [0 ; 2].
Upp[i] = max(U[i][n]), Upm[i] = min(U[i][n]) n ∈ [0 ; N]
Positive and negative peak currents of phase (i+1) with i ∈ [0; 3] (i = 3 ⇔ neutral).
App[i] = max(A[i][n]), Apm[i] = min(A[i][n]) n ∈ [0; N]
Note: The duration of the evaluation is left to the user’s discretion (reset by pressing the

key in the MAX-MIN mode).
16.1.2.6. Peak factors (neutral included except Vcf and Ucf – over one second)
Peak factor of phase-to-neutral voltage of phase (i+1) with i ∈ [0; 2].
[ ]
[ ] [ ]
[ ][ ]
∑
−
=
⋅
=
1
0
2
1
)iVpm,iVppmax(
Vcf
NechSec
n
niV
NechSec
i
Peak factor of phase-to-phase voltage of phase (i+1) with i ∈ [0 ; 2].
[ ]
[ ]
[ ]
[ ][ ]
∑
−
=
⋅
=
1
0
2
1
)iUpm,iUppmax(
Ucf
NechSec
n
niU
NechSec
i