Table of Contents
Advertisement
1MRK 505 370-UEN D
Curve name
Instantaneous
IEC Reset (constant time)
ANSI Reset (inverse time)
The different reset characteristics are described in the Technical Reference Manual (TRM).
There are some restrictions regarding the choice of reset delay.
For the independent time delay characteristics the possible delay time settings are
instantaneous (1) and IEC (2 = set constant time reset).
For ANSI inverse time delay characteristics all three types of reset time characteristics are
available; instantaneous (1), IEC (2 = set constant time reset) and ANSI (3 = current dependent
reset time).
For IEC inverse time delay characteristics the possible delay time settings are instantaneous
(1) and IEC (2 = set constant time reset).
For the programmable inverse time delay characteristics all three types of reset time
characteristics are available; instantaneous (1), IEC (2 = set constant time reset) and ANSI (3 =
current dependent reset time). If the current dependent type is used settings
must be given.
tPCrvx , tACrvx , tBCrvx , tCCrvx : Parameters for programmable inverse time characteristic
curve. The time characteristic equation is according to equation 37:
æ
ç
ç
[ ] =
t s
ç
ç
è
EQUATION1189 V1 EN-US
Further description can be found in the Technical reference manual (TRM).
tPRCrvx , tTRCrvx , tCRCrvx : Parameters for customer creation of inverse reset time
characteristic curve. Further description can be found in the Technical Reference Manual.
7.4.3.2
Common settings for all steps
AngleRCA : Relay characteristic angle given in degrees. This angle is defined as shown in
figure 98. The angle is defined positive when the residual current lags the reference voltage
(Upol = -U2)
Busbar protection REB670
Application manual
ö
÷
A
÷
+
×
B
k
÷
p
æ
ö
i
-
C
ç
÷
÷
è
>
ø
ø
in
x means step 1, 2, 3 and 4.
Section 7
Current protection
pr , tr and cr
(Equation 37)
GUID-A00A942B-E760-42EE-8FEB-F723426783F3 v1
169
Advertisement
Table of Contents
