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1MRK 511 451-UEN Rev. C
Diff.
Current
Values transferred
to the SCS
IEC18000308 V1 EN-US
Figure 5:
To stabilize the display during normal operation, differential currents below the zero limit
(dead band) count as zero and are transferred as such.
Providing the condition for transmitting a current value is fulfilled, all the differential currents
belonging to the respective zone are sent to the SCS/SMS.
Example 1
sum = sum + |current – last|
if sum > delta then
sum = 0
if current < deadband then
endif
send current
endif
last = current
The system continuously performs the above algorithm: It adds up the absolute difference
between the last two measurements (current and last) since the last status update was sent
(sum).
As soon as sum is greater than the threshold delta a new event will be sent with the current
value. If this value is below the deadband threshold, the value 0 will be sent instead.
3.4.2
Configuring the SCS differential current parameter
The precise conditions for sending differential currents to the SCS can be set by selecting
HMI500 Settings/Communication/SCS Diff. Current Parameters.
Distributed busbar protection REB500
Communication protocol manual IEC 60870-5-103
0
Transmitted values and the zero limit
current = 0
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12000189-IEC18000308-1-en.vsd
Interbay bus functions
Zero limit
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GUID-DF29CA42-6DDD-459D-A610-175B597D83C9 v2
Section 3
11
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