ABB RELION REX640 Technical Manual page 1018

Section 4
Protection functions
1012
GUID-E802D1A0-4F27-4309-A24D-E8AA988EA3FB V1 EN
Figure 548: Frequency response of the peak integrated current calculator
Operate level detector
The Operate level detector compares I_PEAK_INT_x value to Start value overload.
If the phase or phases in which I_PEAK_INT_x exceeds the setting matches the Num
of start phases setting, the Operate level detector module activates the Timer 1
module.
Timer 1
Once activated, the Timer 1 module activates the ST_OVLOD output. The operation
time depends on the overload level and Time multiplier. The operation time under
standard characteristics is based on ANSI/IEEE 37.99 and IEC 60871-1
recommendations.
Table 951: Standard Curve characteristics for IDMT Curve
Overload value
1.10
1.15
1.20
1.30
1.40
1.70
2.20
Operate time is based on maximum value of I_PEAK_INT_A, I_PEAK_INT_B and
I_PEAK_INT_C. From maximum value calculated , operate time between any two
consecutive points in the standard table is based on logarithmic interpolation.
Relay operate time(s) with k = 1
43200
1800
300
60
15
1
0.120
1MRS759142 C
Standard
IEC60871-1
IEC60871-1
IEC60871-1
ANSI/IEEE37.99,IEC60871-1
ANSI/IEEE37.99
ANSI/IEEE37.99
ANSI/IEEE37.99
REX640
Technical Manual