ABB REC670 Applications Manual page 196

Section 8
Current protection
190
Table 24: Inverse time characteristics
Curve name
ANSI Extremely Inverse
ANSI Very Inverse
ANSI Normal Inverse
ANSI Moderately Inverse
ANSI/IEEE Definite time
ANSI Long Time Extremely Inverse
ANSI Long Time Very Inverse
ANSI Long Time Inverse
IEC Normal Inverse
IEC Very Inverse
IEC Inverse
IEC Extremely Inverse
IEC Short Time Inverse
IEC Long Time Inverse
IEC Definite Time
User Programmable
ASEA RI
RXIDG (logarithmic)
See chapter "Inverse time characteristics" in Technical Manual for the description
of different characteristics
tPCrv, tACrv, tBCrv, tCCrv: Parameters for customer creation of inverse time
characteristic curve (Curve type = 17). The time characteristic equation is:
æ
ç
A
ç
[ ] = +
t s B
ç
p
æ ö
i
-
C
ç ç ÷
è > ø
è
in
EQUATION1958 V1 EN-US
tINNonDir is the definite time delay for the non directional earth fault current
protection, given in s.
OpUN> is set On to activate the trip function of the residual over voltage
protection.
tUN is the definite time delay for the trip function of the residual voltage
protection, given in s.
ö
÷
÷
×
InMult
÷
÷
ø
1MRK 511 401-UEN A
(Equation 60)
Bay control REC670 2.2 IEC
Application manual