Measurements and settings
Power Related Measurements
58
TemBreak
PRO
P_SE-UM-001-EN
– V1.2.0
Reactive and apparent power calculation convention
Total reactive (Q
tot
) and apparent (S
tot
) power for a 3-phase-3-wire system are calculated in the P_SE OCR using either Arithmetic or Vector convention,
which is selectable during configuration.
Changes to the reactive and apparent power calculation convention can be made using one or a combination of the below methods:
-
TPED
-
TPCM
TPED setting
TPCM setting
Default
“Calc. convention”
Arithmetic: Arithmetic convention
Vector:
Vector convention
Command ID: 104 “
Calculation formula for Reactive and Apparent power
”
Hex 00 00:
Arithmetic convention
Hex 00 01:
Vector convention
Vector convention
The selection of either convention depends on user or application preference, however, does impact the calculation of other power related measurements
which utilize total reactive (Q
tot
) and apparent (S
tot
) power. Differences between the results of the calculation convention used are more prominent in
unbalanced 3-phase systems.
Arithmetic convention:
Total apparent power (S
totA
) is calculated by adding the absolute magnitude of the apparent power (|S
p
|) of each phase.
S
totA
=
|
S
1
|
+
|
S
2
|
+
|
S
3
|
Therefore, total reactive power (Q
totA
) is calculated by using the known total real power (P
tot
) and the arithmetic S
totA
.
Q
totA
=
±
√
S
totA
2
-
P
tot
2
Vector convention:
Total apparent power (S
totV
) is calculated by adding the known total real power (P
tot
) and total reactive power (Q
totV
).
S
totV
=
√
P
tot
2
+Q
totV
2
The calculation of total reactive power (Q
totV
) is performed by adding the vector sum of the apparent power for each phase
(Q
p
).
Q
totA
=
Q
1
+
Q
2
+
Q
3
Values which are affected by calculation convention setting are as follows:
Variables
Symbols
Total reactive and apparent power
Q
tot
, S
tot
Average reactive and apparent power over interval (Demand power)
Q
tot Dmd
, S
tot Dmd
Maximum Average reactive and apparent power over interval (Demand
power) since the last reset
Max. of each Q
tot Dmd
, S
tot Dmd
Reactive energy produced, consumed, absolute and signed totals
E
r In
, E
r Out
, E
r Abs
, E
r
Apparent energy
E
s
Power factor
PF
1
, PF
2
, PF
3
, PF
tot
Total displacement power factor
Cos
ϕ
tot
Summary of Contents for Terasaki TemBreak PRO P SE Series
Page 106: ...106 TemBreak PRO P_SE UM 001 EN V1 2 0 Annex A Dimensions P160 Dimensions...
Page 107: ...Annex A Dimensions 107 TemBreak PRO P_SE UM 001 EN V1 2 0 P250 Dimensions...
Page 108: ...Annex A Dimensions 108 TemBreak PRO P_SE UM 001 EN V1 2 0 P400 Dimensions...
Page 109: ...Annex A Dimensions 109 TemBreak PRO P_SE UM 001 EN V1 2 0 P630 Dimensions...
Page 111: ...111 TemBreak PRO P_SE UM 001 EN V1 2 0 Annex C I2t Let Through Curves P160_SE...
Page 112: ...Annex C I2t Let Through Curves 112 TemBreak PRO P_SE UM 001 EN V1 2 0 P250_SE...
Page 113: ...Annex C I2t Let Through Curves 113 TemBreak PRO P_SE UM 001 EN V1 2 0 P400_SE...
Page 114: ...Annex C I2t Let Through Curves 114 TemBreak PRO P_SE UM 001 EN V1 2 0 P630_SE...
Page 115: ...115 TemBreak PRO P_SE UM 001 EN V1 2 0 Annex D Peak Let Through Curves P160_SE...
Page 116: ...116 TemBreak PRO P_SE UM 001 EN V1 2 0 P250_SE...
Page 117: ...117 TemBreak PRO P_SE UM 001 EN V1 2 0 P400_SE...
Page 118: ...118 TemBreak PRO P_SE UM 001 EN V1 2 0 P630_SE...
Page 121: ...121 TemBreak PRO P_SE UM 001 EN V1 2 0 This page is intentionally left blank...
