ABB RES670 Technical Manual page 491

1MRK 511 408-UUS A
Phasor measurement unit RES670 2.2 ANSI
Technical manual
EnaAbs
INPUT
ABS
EqualBandHigh
RefSource
REF
SetValue
SetValPrefix
EqualBandLow
IEC15000130 V2 EN-US
Figure 189: Logic diagram for REALCOMP
This function has two settings EqualBandHigh and EqualBandLow to provide margins
from reference value for equal to condition. When the INPUT value is within high and
low band, output INEQUAL will get set.
In order to avoid oscillations at boundary conditions of equal band low limit and high
limit, hysteresis has been provided. If the INPUT is above the equal high level margin
including hysteresis, then INHIGH will set. Similarly if the INPUT is below the equal
low level margin including hysteresis, then INLOW will set.
INEQUAL Reset / INHIGH Set
EqualBandHigh
Equal Band
REF or SetValue
EqualBandLow
INEQUAL Reset / INLOW Set
IEC15000261 V1 EN-US
Figure 190: Operation principle of REALCOMP
T
F
Comparator
ABS T
T
F
F
comparator
INEQUAL Set / INHIGH Reset
Section 15
High
XOR
Low
IEC15000130-2-en.vsdx
Internal
Hysteresis for
equal band
INEQUAL Set / INLOW Reset
IEC15000261-1-en.vsdx
Logic
INHIGH
INEQUAL
INLOW
485