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2.15 It Function (current-time integral)
157
7ST6 Manual
E50417-G1176-C251-A3
In the 7ST6 device the indication
„>Brk Aux NC“
(FNo 4602) is used for this pur-
pose. The device does not detect the opening of the circuit breaker auxiliary contact
until a delay time
t
BI
of approx. 5 ms has elapsed.
Note
The indication
„>Brk Aux NC“
must be allocated to a fast binary input. The binary
inputs BI1 through BI12 must be used for this!
The circuit breaker main contact may open before or after the circuit breaker auxiliary
contact. The time difference between the switching of these two contacts can be set
with the parameter
DELTA AuxCont
(address
4103
). A positive value is set for this
time difference if the auxiliary contact opens or closes later than the main contact.
The figure below illustrates how the time limit for determination of the current integral
is specified. The values used in it are:
tBI
Instant at which the device detects through a binary input BI that the
auxiliary contact Aux is closed.
∆
tBI
Delay time of the binary input.
tAux
Time difference between the main and the auxiliary contact of the
circuit breaker (end of movement of the main contact).
T CB OPENING
Circuit breaker operating time on tripping.
Figure 2-43
Typical course of a trip, including the beginning and end of the integration inter-
val to determine the trip load
Following a TRIP command, the binary inputs for the circuit breaker auxiliary contacts
are monitored for a maximum of 150 ms. If the binary input is activated during that in-
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Содержание SIPROTEC 7ST6
Страница 14: ...Contents 14 7ST6 Manual E50417 G1176 C251 A3 w w w E l e c t r i c a l P a r t M a n u a l s c o m ...
Страница 24: ...1 Introduction 24 7ST6 Manual E50417 G1176 C251 A3 w w w E l e c t r i c a l P a r t M a n u a l s c o m ...
Страница 254: ...3 Mounting and Commissioning 254 7ST6 Manual E50417 G1176 C251 A3 w w w E l e c t r i c a l P a r t M a n u a l s c o m ...
Страница 288: ...4 Technical Data 288 7ST6 Manual E50417 G1176 C251 A3 w w w E l e c t r i c a l P a r t M a n u a l s c o m ...
Страница 340: ...A Appendix 340 7ST6 Manual E50417 G1176 C251 A3 w w w E l e c t r i c a l P a r t M a n u a l s c o m ...
Страница 342: ...Literature 342 7ST6 Manual E50417 G1176 C251 A3 w w w E l e c t r i c a l P a r t M a n u a l s c o m ...
Страница 354: ...Index 354 7ST6 Manual E50417 G1176 C251 A3 w w w E l e c t r i c a l P a r t M a n u a l s c o m ...
Страница 355: ...Index 355 7ST6 Manual E50417 G1176 C251 A3 w w w E l e c t r i c a l P a r t M a n u a l s c o m ...
Страница 356: ...Index 356 7ST6 Manual E50417 G1176 C251 A3 w w w E l e c t r i c a l P a r t M a n u a l s c o m ...