ABB RELION REX640 - Page 1439

Function Settings Minimum/maximum
Phase sequence current measurement
(CSMSQI)
Ps Seq A deadband ,
Ng Seq A deadband ,
Zro A deadband
0.04/40
Phase sequence voltage measurement
(VSMSQI)
Ps Seq V deadband ,
Ng Seq V deadband ,
Zro V deadband
0.004/4
Three-phase power and energy measurement
(PEMMXU)
Power deadband 0.01/0.1
Power and energy calculation
The three-phase power is calculated from the selected voltage and current
measurements as described in Table 1360 . The setting Measurement mode
determines which voltage and current measurements are used.
It is also possible to use positive-sequence components for calculating the apparent
power, which makes the determination of power insensitive to any asymmetry in
currents or voltages.
Table 1360: Measured apparent power
Measurement mode setting
values
Power calculation
PhsA, PhsB, PhsC
S U I U I U IA A B B C C= ⋅ + ⋅ + ⋅
* * *
(Equation 339)
Arone
S U I U IAB A BC C= ⋅ − ⋅
* *
(Equation 340)
Pos Seq
S U I= ⋅ ⋅3 1 1
*
(Equation 341)
PhsAB
S U I IAB A B= ⋅ −
( )
* *
(Equation 342)
PhsBC
S U I IBC B C= ⋅ −
( )
* *
(Equation 343)
PhsCA
S U I ICA C A= ⋅ −
( )
* *
(Equation 344)
Table continues on the next page
1MRS759142 F Measurement functions
REX640
Technical Manual
1439