ABB RELION REX640 Technical Manual page 1438

Measurement functions
Figure 804: Integral deadband supervision
The deadband value used in the integral calculation is configured with the
deadband setting. The value represents the percentage of the difference between
the maximum and minimum limit in the units of 0.001 percent x seconds.
The reporting delay of the integral algorithms in seconds is calculated with the
formula:
t s ( )
Example for CMMXU:
A deadband = 2500 (2.5 % of the total measuring range of 40)
I_INST_A = I_DB_A = 0.30
If I_INST_A changes to 0.40, the reporting delay is:
( )
t s
Table 1359: Parameters for deadband calculation
Function
Three-phase current measurement (CMMXU)
Three-phase voltage measurement (VMMXU)
Phase voltage measurement (VMHMMXU)
Single-phase voltage measurement (VAMM-
XU)
Residual current measurement (RESCMMXU)
Residual voltage measurement (RESVMMXU)
Frequency measurement (FMMXU)
Table continues on the next page
1438
deadband
(max min) − ×
=
∆ Y × 100 %
( 40 0 ) 2500 1000 /
− ×
= =
0 40 0 30 100 . . %
− ×
/ 1000
10
s
Settings
A deadband
V deadband
V deadband
V deadband
A deadband res
V deadband res
F deadband
1MRS759142 F
X
(Equation 338)
Minimum/maximum
0.04/40
0.004/4
0.004/4
0.004/4
0.04/40
0.004/4
0.04/40
REX640
Technical Manual